JP2013139351A - Copolymer for cement admixture, method for producing the same, and cement admixture containing copolymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a copolymer for a cement admixture, concerning a cement admixture essentially including a copolymer in a ternary or higher system, capable of producing easily a copolymer in which the composition of a monomer generated in one-time polymerization operation is furthermore uniformized or a blend of a plurality of copolymers having each different monomer composition, and controlling easily the monomer composition ratio or the blending ratio of the copolymers, and having excellent water reducing performance and/or retainability, and to provide a method for producing the same.SOLUTION: In this method for producing a copolymer for a cement admixture having a polymerization stage for polymerizing a monomer component containing an unsaturated polyalkylene glycol ether-based monomer (A), an unsaturated organic acid-based monomer (B), and an unsaturated carboxylic ester-based monomer (C), in the polymerization stage, two or more components are added continuously into a reaction system, and at least two components among the continuously added components are added into the reaction system by changing at least once addition speed thereof.

Description

  The present invention relates to a copolymer for cement admixture, a method for producing the same, and a cement admixture containing the copolymer.

  Cement admixture is widely used as a water reducing agent for cement compositions such as cement paste, mortar, and concrete, and is indispensable for building civil engineering and building structures from cement compositions. It has become. Such a cement admixture has the effect of improving the strength and durability of a cured product by increasing the fluidity of the cement composition and reducing the water content of the cement composition. Water-soluble vinyl copolymer of naphthalene condensate, melamine sulfonic acid formalin condensate, polyalkylene glycol monoester monomer and (meth) acrylic acid and / or dicarboxylic acid monomer A polycarboxylic acid system that is a coalescence is known. Among such water reducing agents, in particular, polycarboxylic acid polymers exhibit high water reducing performance compared to conventional water reducing agents such as naphthalene, so a cement admixture containing this polycarboxylic acid polymer is There are many achievements as a high-performance AE water reducing agent.

  In such a cement admixture, in addition to the water reducing performance of the cement composition, a cement admixture that can improve the viscosity is required in consideration of workability in the field where the cement composition is handled. Yes. Generally, a cement admixture used as a water reducing agent exhibits excellent water reducing performance by lowering the viscosity of the cement composition. In addition to such water reducing ability, the cement admixture is handled. In order to facilitate the work on site, it is required to maintain a certain degree of viscosity in the production site of civil engineering and building structures. When the cement admixture exhibits such performance, work efficiency and the like in construction of civil engineering and building structures will be improved.

  For the above purpose, various cement admixtures have been proposed.

  For example, Patent Document 1 discloses a binary or ternary cement admixture that can exhibit excellent dispersibility and flowability. The cement admixture disclosed in Patent Document 2 has the general formula (a):

(Wherein R ₁ and R ₂ are a hydrogen atom or a methyl group, m is a number from 0 to 2, R ₃ is a hydrogen atom or COO (AO) _n X, and p is 0 Or AO is an oxyalkylene group having 2 to 4 carbon atoms or an oxystyrene group, n is a number having 2 to 300, and X is a hydrogen atom or an alkyl having 1 to 18 carbon atoms. At least one monomer represented by (A) and a general formula (b):

(Wherein R _{4 to} R ₆ are a hydrogen atom, a methyl group, or (CH ₂ ) _m1 COOM ₂ , and (CH ₂ ) _m1 COOM ₂ represents COOM ₁ or other (CH ₂ ) _m1 COOM ₂ and an anhydride In this case, M ₁ and M ₂ of these groups are not present; M ₁ and M ₂ are a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an alkylammonium group, or a substituent. Concrete mixture containing a copolymer mixture obtained by copolymerizing at least one monomer (B) which is an alkylammonium group and m1 represents a number of 0 to 2). An agent that changes the molar ratio (A) / (B) of the monomers (A) and (B) at least once during the reaction.

  Patent Document 2 discloses at least three types of ethylene monomer (A) having a polyoxyalkylene group, unsaturated organic acid monomer (B), and other unsaturated monomer (C). In a cement admixture which essentially requires a ternary or higher copolymer obtained by polymerizing a monomer component containing a monomer, an ethylene monomer having a polyoxyalkylene group in the copolymer A cement admixture in which the molar ratio of (A) to other unsaturated monomer (C) is changed during polymerization is disclosed.

  In Patent Document 3, an unsaturated organic acid monomer (B) is added to an unsaturated polyalkylene glycol ether monomer (A) at an addition rate of at least once to be unsaturated. A method for producing a copolymer for a cement admixture having a step of polymerizing a polyalkylene glycol ether monomer (A) and an unsaturated organic acid monomer (B) is disclosed. In this document, a copolymer in which the composition of the monomer to be produced is made more uniform in a single polymerization operation by performing a polymerization reaction by changing the addition rate stepwise, or a monomer A plurality of copolymer blends of different compositions can be easily produced, and such a polymer mixture can be made slump-retainable by increasing or decreasing the rate of addition before or after each addition step. It has been found that it has excellent water reduction performance.

JP 2001-180998 A JP 2004-182583 A JP 2006-248889 A

  Among the cement admixtures disclosed in the above patent documents, in Patent Document 1, in paragraph 0021, “The copolymer mixture has a step of polymerizing by changing the (A) / (B) molar ratio at least once. Although it is obtained by the production method, specifically, the addition of the monomer (B) is started simultaneously with the start of the dropwise addition of the aqueous solution of the monomer (A), " The cement admixture is produced by simultaneously dripping the bodies (A) and (B). At this time, when an ester monomer having p of 1 in the above formula (a) is used as the monomer (A), the polymerizable properties of the monomers (A) and (B) are almost the same. Therefore, even when the monomers (A) and (B) are dropped simultaneously, the copolymerization reaction of these monomers proceeds efficiently. However, when an ether monomer having p of 0 in the formula (a) is used as the monomer (A), the monomer (A) has low self-polymerizability (monomer (A) is difficult to be continuously incorporated into the copolymer), the monomer (A) has a low degree of homopolymerization, whereas the monomer (B) has a high degree of reactivity. Therefore, only the added monomer (B) is preferentially subjected to polymerization, or in some cases, only the monomer (B) is subjected to polymerization, and the monomer (A ) Reaction rate may be low. That is, since the copolymerization property of the monomer (A) is low, the copolymerization reaction may not proceed efficiently.

  Further, the cement admixture disclosed in Patent Document 2 has excellent slump retention properties such as cement composition so that fluidity is maintained, and it is easy to work in the field where the cement composition is handled. Although it was developed for the purpose of achieving such a viscosity, it has not yet fully satisfied all the water reduction performance, slump retention and viscosity.

  The cement admixture disclosed in Patent Document 3 is excellent in slump retention or water-reducing performance. In this case, the slump retention property or water reduction performance has not been satisfied yet.

  Accordingly, the present invention has been made in view of the above circumstances, and a monomer produced by a single polymerization operation in a cement admixture in which a ternary or higher copolymer is essential. Copolymers with a more uniform composition, or multiple copolymer blends with different monomer compositions can be easily produced, and the monomer composition ratio and copolymer blend ratio can be easily controlled. And a copolymer for a cement admixture excellent in water reducing performance and / or retention, a method for producing the same, a cement admixture containing the copolymer, and a cement composition containing such a cement admixture It is intended.

  Another object of the present invention is to provide a copolymer exhibiting excellent water reduction performance and a cement admixture containing the copolymer.

  Still another object of the present invention is to provide a cement admixture that maximizes cement dispersibility by specifying the raw materials used in the production of the copolymer.

  In order to achieve the above object, the present inventors have developed an unsaturated polyalkylene glycol ether monomer (A), an unsaturated organic acid monomer (B), and an unsaturated carboxylic acid ester monomer (C As a result of intensive studies on a method for producing a copolymer for a cement admixture having a polymerization stage for polymerizing a monomer component containing 2), two or more components are continuously added to the reaction system in the polymerization stage. By changing the addition rate of at least two of the continuously added components to the reaction system at least once, the composition of the monomer to be produced can be made more uniform in one polymerization operation. Or a plurality of copolymer blends having different monomer compositions, and a mixture of such polymers can increase the rate of addition before and after each addition step. Slow down And the found to become excellent in slump retention ability or water reducing performance.

  Moreover, the present inventors added two or more components continuously to the reaction system in the average monomer composition of the entire copolymer mixture, and at least two components among the components added continuously. By slowing the addition rate of the polymer at a later stage, a copolymer with a more uniform monomer composition ratio in the mixture can be produced, and this copolymer has a particularly excellent water reduction performance due to a single monomer composition. On the other hand, if the addition rate of at least two of the continuously added components is increased at a later stage, a copolymer blend with a moderately different monomer composition ratio in the mixture can be produced. It has also been found that polymer blends are particularly excellent in slump retention due to different monomer compositions. In particular, the present inventors have also found that the former copolymer can exhibit superior water reduction performance as compared with a polycarboxylic acid copolymer that exhibits excellent water reduction performance.

  Based on the above findings, the present invention has been completed.

  That is, the above object is achieved by the following formula (1):

Where
R ¹ , R ² and R ³ each independently represents a hydrogen atom or a methyl group,
R ^a O each independently represents one or more of oxyalkylene groups having 2 or more carbon atoms,
m represents a number of 1 to 300 in terms of the average number of moles added of the oxyalkylene group;
x represents an integer of 0 to 2;
y represents 0 or 1,
R ⁴ represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms,
At least one unsaturated polyalkylene glycol ether monomer (A) represented by the following formula (2):

Where
R ⁵ , R ⁶ and R ⁷ are each independently a hydrogen atom, a methyl group or — (CH ₂ ) _z COOM ² group (— (CH ₂ ) _z COOM ² is —COOM ¹ or other — (CH ₂ ) _z COOM ² and may form an anhydride), z represents an integer of 0-2;
M ¹ and M ² each independently represent a hydrogen atom, an alkali metal atom, an alkaline earth metal atom, an ammonium group or an organic ammonium group.
And at least one unsaturated organic acid monomer (B) represented by the following formula (3):

Where
R ⁸ , R ⁹ and R ¹⁰ each independently represent a hydrogen atom, a methyl group, or — (CH ₂ ) _n COOR ¹² group, and n represents an integer of 0 to 2;
R ¹¹ and R ¹² represent a C 1-20 alkyl group having a C 1-20 alkyl group, a C 1-20 hydroxyalkyl group, or a C 1-20 alkoxy group,
A method for producing a copolymer for a cement admixture having a polymerization step for polymerizing a monomer component containing at least one unsaturated carboxylic acid ester monomer (C) represented by the formula: Two or more components are continuously added to the reaction system, and at least two of the continuously added components are added to the reaction system at least once, and then added to the reaction system. This is achieved by the manufacturing method of coalescence.

  According to the present invention, in a cement admixture in which a ternary or higher copolymer is indispensable, the composition of monomers generated in a single polymerization operation without a complicated process is more uniform. Can be produced, or a blend of a plurality of copolymers with different monomer compositions can be produced, so it is not necessary to produce a copolymer separately and then mix to produce a blend of copolymers, The manufacturing process can be considerably simplified. Further, by using such a copolymer blend as a cement admixture, a cement admixture excellent in water reduction performance and / or slump retention can be produced. In particular, the copolymer according to the present invention can exhibit excellent water-reducing performance as compared with conventional polycarboxylic acid-based copolymers, and therefore can be suitably used as a high-performance AE water reducing agent.

  The cement admixture according to the present invention improves the water-reducing performance of cement compositions such as cement paste, mortar, concrete, etc., and has excellent strength and durability of the cured product. The fluidity can be maintained by increasing the viscosity, and the viscosity can be made easy to work at the site where cement is handled. Therefore, by using the cement admixture according to the present invention, work efficiency and the like can be improved in the construction of civil engineering and building structures having excellent basic performance.

  The present invention provides the following formula (1):

At least one unsaturated polyalkylene glycol ether monomer (A) (hereinafter, also simply referred to as “monomer (A)”) represented by the following formula (2):

And at least one unsaturated organic acid monomer (B) (hereinafter also simply referred to as “monomer (B)”), and the following formula (3):

For cement admixture having a step of polymerizing a monomer component containing at least one unsaturated carboxylic acid ester monomer (C) (hereinafter also simply referred to as “monomer (C)”) A method for producing a copolymer, wherein in the polymerization step, two or more components are continuously added to the reaction system, and the addition rate of at least two of the continuously added components is changed at least once. The present invention provides a method for producing a copolymer for a cement admixture that is added to a reaction system. This is because of the difference in reactivity between the unsaturated polyalkylene glycol ether monomer (A), the unsaturated organic acid monomer (B), and the unsaturated carboxylic acid ester monomer (C). It is used.

  According to such a polymerization method, the copolymer made the composition of the monomer more uniform by changing the addition rate of at least two components among the components added continuously in one polymerization operation ( Copolymers or blends of two or more types of copolymers with different monomer compositions can be produced, and the copolymer structure (monomer composition) and copolymer By appropriately adjusting the blend ratio, the cement admixture containing the blend can sufficiently exhibit a desired effect (for example, water reduction performance and / or slump retention). Further, the change in the addition rate of at least two of the continuously added components may be performed either continuously or stepwise, but if performed stepwise, a special apparatus is required. In addition, the addition rate can be easily adjusted, and the structure (monomer composition) of the polymer to be produced can be easily adjusted, so that a desired effect (for example, water reduction performance and / or slump retention) can be obtained. It is easy to produce a cement admixture having

  In one embodiment of the present invention, the component continuously added to the reaction system in the polymerization stage is selected from the group consisting of a polymerization component and a component involved in the polymerization reaction. The polymerization components are monomer (A), monomer (B) and monomer (C), and the components involved in the polymerization reaction are polymerization initiator (D), reducing agent (E), and It is a chain transfer agent (F). That is, as one form of the present invention, the components continuously added to the reaction system in the polymerization stage are monomer (A), monomer (B), monomer (C), polymerization initiator. (D), at least two or more components selected from the group consisting of a reducing agent (E) and a chain transfer agent (F), and at least two of the continuously added components are: The addition rate is changed at least once and added to the reaction system.

  Moreover, the other form of this invention is an unsaturated organic acid monomer (B), an unsaturated carboxylic acid ester monomer (C), a polymerization initiator (D), a reducing agent (E), and a chain. At least two components selected from the group consisting of transfer agent (F) are added to the reaction system with the addition rate changed at least once.

  In still another embodiment of the present invention, the unsaturated polyalkylene glycol ether monomer (A) having low reactivity is collectively collected before polymerization with the monomer (B) and the monomer (C). After being added to the reaction vessel, at least 2 selected from the group consisting of monomer (B), monomer (C), polymerization initiator (D), reducing agent (E), and chain transfer agent (F) Two components are added to the monomer (A) at an addition rate of at least once to polymerize these monomers (A), (B) and (C).

  According to such a polymerization method, the copolymer has a more uniform monomer composition (change in monomer composition) by changing the addition rate of the polymerization component and the component involved in the polymerization reaction in a single polymerization operation. Copolymers with little variation) or blends of two or more copolymers with different monomer compositions can be produced, and copolymers with different copolymer structures (monomer compositions) and monomer compositions By appropriately adjusting the blend ratio, the cement admixture containing this blend can sufficiently exhibit the desired effect (for example, water reduction performance and / or slump retention). The addition rate of at least two components selected from the group consisting of monomer (B), monomer (C), polymerization initiator (D), reducing agent (E), and chain transfer agent (F) However, if the change is made stepwise, the addition rate can be easily adjusted without the need for a special apparatus, and the produced polymer Therefore, it is easy to produce a cement admixture having a desired effect (for example, water reduction performance and / or slump retention).

  Furthermore, in another embodiment of the present invention, the unsaturated polyalkylene glycol ether monomer (A), the monomer (B) and the monomer (C) are simultaneously, continuously or stepwise. At least two components selected from the group consisting of a polymerization initiator (D), a reducing agent (E), and a chain transfer agent (F) that are components added to the reaction vessel and simultaneously added to the reaction vessel Is added to the monomers (A), (B) and (C) with the addition rate changed at least once, to polymerize these monomers (A), (B) and (C). To do.

  According to such a polymerization method, the copolymer has a more uniform monomer composition (less variation in monomer composition) due to a change in the rate of addition of components involved in the polymerization reaction in a single polymerization operation. ) Copolymers or blends of two or more types of copolymers can be manufactured, and by appropriately adjusting the copolymer structure (monomer composition) and the blend ratio of copolymers having different monomer compositions The cement admixture containing this blend can sufficiently exhibit the desired effects (for example, water reduction performance and / or slump retention). The addition rate of at least two components selected from the group consisting of the polymerization initiator (D), the reducing agent (E), and the chain transfer agent (F) is changed either continuously or stepwise. However, if it is performed stepwise, the addition rate can be easily adjusted without requiring a special device, and the structure (monomer composition) of the polymer to be produced can be easily adjusted. Therefore, it is easy to produce a cement admixture having a desired effect (for example, water reduction performance and / or slump retention).

  Hereinafter, the present invention will be described in detail.

  The method for producing a copolymer according to the present invention comprises a step of copolymerizing at least three monomer components of monomer (A), monomer (B) and monomer (C). In this case, the monomer (A), the monomer (B) and the monomer (C) are each used alone or in a mixture of two or more. It may be used in the form. Moreover, although explained in full detail below, in addition to the said monomer (A), a monomer (B), and a monomer (C), even if it uses a 4th unsaturated monomer (X). In this case, the fourth unsaturated monomer (X) may be used alone or in the form of a mixture of two or more.

  The copolymer according to the present invention comprises at least three types of monomer components, monomer (A), monomer (B) and monomer (C). Has a function of exerting dispersibility in the cement composition due to the hydrophilicity and steric repulsion of the polyoxyalkylene group, and the monomer (B) can adsorb the copolymer to the cement particles. It has a function of increasing the hydrophilicity of the copolymer. In the present invention, in the polymerization stage, two or more components are continuously added to the reaction system, and the addition rate of at least two of the continuously added components is changed at least once and added to the reaction system. The monomer (A), monomer (B) and monomer (C) are then copolymerized to produce the monomer (A), monomer (B) and monomer (C ) In different composition ratios are produced, the dispersibility of the monomer (A) in the cement composition, and the ability of the monomer (B) to adsorb the copolymer on cement particles and the copolymer It is possible to produce a blend of copolymers in which the hydrophilicity is appropriately adjusted so as to achieve a desired effect. As described in detail below, this makes it possible to produce a cement admixture excellent in water reduction performance and / or slump retention.

  In this invention, it is preferable that the component added continuously contains at least 1 selected from the group which consists of a polymerization initiator (D), a reducing agent (E), and a chain transfer agent (F). In addition, the components continuously added to the reaction system in the polymerization stage are monomer (A), monomer (B), monomer (C), polymerization initiator (D), and reducing agent (E). And at least two or more components selected from the group consisting of a chain transfer agent (F). More preferably, the components continuously added to the reaction system in the polymerization stage are monomer (B), monomer (C), polymerization initiator (D), reducing agent (E), and chain transfer agent. It is at least two or more components selected from the group consisting of (F). Among these continuously added components, at least two components are added to the reaction system by changing the addition rate at least once. In the present invention, in particular, at least two selected from the group consisting of monomer (B), monomer (C), polymerization initiator (D), reducing agent (E), and chain transfer agent (F) It is preferable to change the addition rate of the components at least once and add them to the reaction system.

  In the present invention, examples of the component added to the reaction system by changing the addition rate at least once (hereinafter also referred to as “addition rate changing component”) include, for example, the monomer (A) and the monomer. (B), monomer (A) and monomer (C), monomer (B) and monomer (C) in two cases; monomer (A) and polymerization initiation Two cases of a polymerization component such as an agent (D), a monomer (B) and a polymerization initiator (D), a monomer (C) and a polymerization initiator (D) and a component involved in the polymerization reaction; (D) and the reducing agent (E), the polymerization initiator (D) and the chain transfer agent (F), the reducing agent (E) and the two components involved in the polymerization reaction such as the chain transfer agent (F); Two of the polymerization components such as the monomer (B), the monomer (C) and the polymerization initiator (D) For three in one of the components involved in the coupling reaction; includes forms such as. In the case where the “component continuously added” of the present invention is two components selected from the group consisting of the monomer (A), the monomer (B) and the monomer (C) The addition rate changing component is also two components selected from the group consisting of the monomer (A), the monomer (B) and the monomer (C), so that the polymerization initiator (D), reduction The agent (E) and the chain transfer agent are not essential components in the present invention. In the present specification, the “reaction system” means a system in which the monomer (A), the monomer (B) and the monomer (C) are copolymerized. It means that A), the monomer (B) and the monomer (C) are added to a “reaction vessel” for copolymerization.

  As described above, one form of the production method of the present invention includes the monomer (B), the monomer (C), the polymerization initiator (D), the reducing agent (E), and the chain transfer agent (F). The addition rate of at least two components selected from the group consisting of is changed at least once.

  For example, in one production method of the present invention, the monomer (B), the monomer (C), the polymerization initiator (D), and the reducing agent (E) are added to the monomer (A) added in advance. And the addition rate of at least two components selected from the group consisting of the chain transfer agent (F) is changed at least once. In addition, the other production method of the present invention is such that the monomer (A), the monomer (B) and the monomer (C) are added simultaneously or continuously to the reaction vessel, and then polymerized. The addition rate of at least two components selected from the group consisting of a polymerization initiator (D), a reducing agent (E), and a chain transfer agent (F), which are components involved in the reaction, is changed at least once. To do. In the present specification, “unsaturated polyalkylene glycol ether monomer (A) previously added to the reaction vessel” means that the monomer (A) is initially added in its entirety to the reaction vessel. It means adding. “Initial” refers to the period immediately before the start of the copolymerization reaction with another monomer, that is, the monomer (B) and / or the monomer (C). B) and / or before adding monomer (C), more preferably before adding monomer (B) and / or monomer (C) and polymerization initiator (D). . The number of times of changing the addition rate is not particularly limited, and can be appropriately selected depending on the desired characteristics of the cement admixture to be manufactured (the degree of emphasis on water reduction performance or slump retention), workability, and the like. 10 times, more preferably 1 to 5 times, even more preferably 1 to 3 times, and most preferably 1 to 2 times. At this time, if the addition rate is changed 11 times or more, improvement in characteristics commensurate with the increase in the number of times cannot be expected, and the workability of the polymerization operation may be complicated. In the present invention, when the addition rate of the addition rate changing component is changed stepwise, the addition rate changing component in each step of adding the addition rate changing component at a constant rate is added continuously or stepwise. The polymerization rate of the monomer (A) may be added either continuously or stepwise in combination, but the addition rate changing component may be continuously added to the monomer (A). It is preferable for improvement. Furthermore, in the present invention, in order to avoid the possibility that only the monomer (B) or the monomer (C) is subjected to polymerization among the addition rate changing components, the monomer (B) The body (C) is preferably added continuously. In addition, as a continuous addition method, the method of dripping continuously is mentioned, for example, The method etc. which are divided | segmented into a fixed ratio are mentioned as a stepwise method, for example.

  In the present invention, the addition rate of the addition rate changing component may be changed either continuously or stepwise, or a combination of continuous and stepwise, but no special equipment is required. It is preferable to change the addition rate stepwise because the addition rate can be easily adjusted and the structure of the polymer to be produced can be easily adjusted. In addition, changing the addition rate stepwise means that the addition amount of the addition rate change component at a certain specific step, that is, the addition rate is almost constant. At this time, the addition rate at a certain specific step The variation of the addition amount / addition rate of the variable component is adjusted within a range of ± 15%, more preferably ± 10%, most preferably ± 5% of the desired addition amount / addition rate. Further, the addition rate change form of the addition rate change component may be either increase or decrease, and in one polymerization step, the addition rate is increased and decreased (for example, the increase and decrease of the addition rate are alternated). It is also possible to change In this way, by increasing or decreasing the addition rate stepwise or continuously, various performances when the produced copolymer is used in a cement admixture (for example, water reduction performance and slump retention properties). Improvement) can be achieved. It should be noted that what kind of performance is preferentially improved, such as water reduction performance and slump retention, depends on the type and amount of monomer (A), monomer (B) and monomer (C). The type and amount of the fourth unsaturated monomer (X), the type involved in the polymerization reaction (polymerization initiator (D), reducing agent (E), chain transfer agent (F)) It depends on the amount.

  Hereinafter, unsaturated polyalkylene glycol ether monomer (A), unsaturated organic acid monomer (B) and unsaturated carboxylic acid ester monomer (C), which are raw materials for the cement admixture of the present invention. ) And the third unsaturated monomer (X) which may be mixed if necessary. Moreover, the polymerization initiator (D), the reducing agent (E), and the chain transfer agent (F), which are components involved in the polymerization reaction, will also be described.

  The unsaturated polyalkylene glycol ether monomer (A) according to the present invention is a compound represented by the following formula (1).

In the above formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a methyl group, and R ^a O each independently represents 1 of an oxyalkylene group having 2 or more carbon atoms. Or m represents an average added mole number of the oxyalkylene group and represents a number of 1 to 300, x represents an integer of 0 to 2, y represents 0 or 1, and R ⁴ Represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.

  That is, the unsaturated polyalkylene glycol ether monomer (A) in the present invention has a polymerizable ethylene group and a polyalkylene glycol chain, and an alcohol polyalkylene glycol adduct having an ethylene group is suitable. .

In the formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a methyl group. R ^a O independently represents one or more oxyalkylene groups having 2 or more carbon atoms. R ^a is preferably an alkylene group having 2 to 18 carbon atoms. In this case, the alkylene group may be linear or branched. In the formula (1), when m is 2 or more, the oxyalkylene groups represented by R ^a O may be the same or different. Examples of “R ^a ” constituting such an oxyalkylene group include an ethylene group (—CH ₂ CH ₂ —), a trimethylene group (—CH ₂ CH ₂ CH ₂ —), and a tetramethylene group (—CH ₂ CH ₂ CH ₂ CH ₂ —), a pentamethylene group, a hexamethylene group, etc., a linear alkylene group, an ethylidene group [—CH (CH ₃ ) —], a propylene group (methylethylene group) [—CH (CH ₃ ) CH ₂ -], propylidene _{[-CH (CH 3 CH 2)} -], isopropylidene radical _{[-C (CH 3) 2 -} ], ethyl ethylene group, such as 1,2-dimethylethylene group, a branched chain Examples thereof include an alkylene group substituted with an aryl group such as an alkylene group and a phenylethylene group. That is, in the formula (1), “R ^a O” is an oxyalkylene group (for example, oxyethylene group) containing the above functional group. Therefore, such an oxyalkylene group represented by — (R ^a O) — is an alkylene oxide adduct having 2 or more carbon atoms, and the structure of such an alkylene oxide adduct has ethylene oxide, propylene oxide, There is a structure formed by one or more of alkylene oxides such as butylene oxide, isobutylene oxide, 1-butene oxide, and 2-butene oxide. Of these, from the viewpoint of reactivity in polymerization, ethylene oxide, propylene oxide, and butylene oxide adducts are preferable, and those mainly composed of ethylene oxide are particularly preferable. The proportion of ethylene oxide in the total oxyalkylene group when the oxyalkylene group represented by-(R ^a O)-is mainly ethylene oxide is not particularly limited, but is preferably 50 to 100 mol%, more preferably 75 to 100 mol%. In some cases, two or more different R ^a O structures may be present in the repeating unit represented by (R ^a O) _m . However, in consideration of the ease of production of the polyoxyalkylene chain and the ease of control of the structure, the repeating structure represented by (R ^a O) _m is preferably the same R ^a O structure. . In addition, when two or more different R ^a O structures exist, these different R ^a O structures may exist in any form such as random addition, block addition, and alternate addition.

  In the formula (1), m represents the number of moles of the oxyalkylene group added and represents a number of 1 to 300, preferably 1 to 250, more preferably 1 to 200, still more preferably 1 to 170. Especially preferably, it is 1-150, Most preferably, it is 1-130. If the average added mole number m of the oxyalkylene group is not less than the above-mentioned lower limit value, it is preferable because the hydrophilicity of the resulting polymer is secured and the dispersion performance can be improved. Moreover, it is preferable if the average added mole number m of the oxyalkylene group is equal to or less than the above-described upper limit value because the reactivity in the reaction step can be sufficiently ensured. The “average number of moles added” means the average number of moles of oxyalkylene groups added in 1 mole of polyether monomer. In addition, as a monomer (A) of the formula (1) having the polyoxyalkylene group, two or more types of monomers having different average added mole numbers m of oxyalkylene groups can be used in combination.

  The distribution of the oxyalkylene group is not limited, and for example, the distribution may be broadened by mixing m having 1 to 10 and 10 to 75, or using a Lewis acid or a solid acid catalyst. By synthesizing, the distribution of the oxyalkylene group may be narrowed.

In the formula (1), x represents an integer of 0 to 2, and y represents 0 or 1. R ⁴ represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. Here, examples of the hydrocarbon group having 1 to 20 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like. An aliphatic or alicyclic alkyl group having 1 to 20 carbon atoms; an aryl group having 6 to 20 carbon atoms such as phenyl, naphthyl, anthryl, phenanthryl; o-, m- or p-tolyl, 2,3- or Aryl groups substituted with alkyl groups such as 2,4-xylyl, mesityl; aryl groups substituted with (alkyl) phenyl groups such as biphenylyl; substituted with aryl groups such as benzyl, phenethyl, benzhydryl, trityl, etc. And alkyl groups. In R ⁴ , as the number of carbon atoms in the hydrocarbon group increases, the hydrophobicity increases and the dispersibility decreases. Therefore, the number of carbon atoms in the case where R ⁴ is a hydrocarbon group is preferably 1-18. 1 to 12 are more preferable, and 1 to 4 are particularly preferable. Furthermore, R ⁴ is most preferably a methyl group or a hydrogen atom.

Examples of the unsaturated polyalkylene glycol ether monomer (A) represented by the formula (1) include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol, 1 - hexanol, octanol, 2-ethyl-1-hexanol, nonyl alcohol, lauryl alcohol, cetyl alcohol, saturated aliphatic alcohols having 1 to 20 carbon atoms such as stearyl alcohol, vinyl alcohol _{(CH 2 = CH-OH)} , 1 - methyl - vinyl alcohol _{(CH 2 = C (CH 3} ) -OH), 2- propen-1-ol (allyl _{alcohol) (CH 2 = CHCH 2 -OH} ), 2- methyl-2-propen-1-ol (methallyl _{alcohol) (CH 2 = C (CH} 3) -CH 2 -OH), 2- butene 1-ol (crotyl _{alcohol) (CH 3 CH = CHCH 2} -OH), 3- buten-1-ol _{(CH 2 = CHCH 2 CH 2} -OH), 3- methyl-3-butene-1 - ol _{(isoprenol) (CH 2 = C (CH} 3) -CH 2 CH 2 -OH), 3- methyl-2-buten-1-ol _{(CH 3 C (CH 3)} = CHCH 2 -OH), 2 - methyl-3-buten-1-ol _{(CH 2 = CHCH (CH 3} ) -CH 2 -OH), 2- methyl-2-buten-1-ol _{(CH 3 CH = C (CH} 3) -CH 2 -OH), unsaturated aliphatic alcohols having 2 to 20 carbon atoms such as oleyl alcohol, alicyclic alcohols having 3 to 20 carbon atoms such as cyclohexanol, phenol, phenylmethanol (benzyl alcohol), An alkylene oxide having 2 or more carbon atoms is added to any of aromatic alcohols having 6 to 20 carbon atoms such as ruphenol (cresol), p-ethylphenol, dimethylphenol (xylenol), nonylphenol, dodecylphenol, phenylphenol and naphthol. Alkoxypolyalkylene glycols (alcohol alkylene oxide adducts) obtained by addition, esters of the alkoxypolyalkylene glycols (alcohol alkylene oxide adducts) with unsaturated carboxylic acids such as (meth) acrylic acid and crotonic acid And one or more of these can be used.

Of these, (1) vinyl alcohol _{(CH 2 = CH-OH)} , 1- methyl - vinyl alcohol _{(CH 2 = C (CH 3} ) -OH), 2- propen-1-ol (allyl alcohol) (CH ₂ = CHCH ₂ -OH), 2- methyl-2-propen-1-ol (methallyl _{alcohol) (CH 2 = C (CH} 3) -CH 2 -OH), 2- buten-1-ol (crotyl _{alcohol) (CH 3 CH = CHCH 2} -OH), 3- buten-1-ol _{(CH 2 = CHCH 2 CH 2} -OH), 3- methyl-3-buten-1-ol (isoprenol) (CH _{2 = C (CH 3) -CH} 2 CH 2 -OH), 3- methyl-2-buten-1-ol _{(CH 3 C (CH 3)} = CHCH 2 -OH), 2- methyl-3-butene - 1-ol ( _{CH 2 = CHCH (CH 3)} -CH 2 -OH), 2- methyl-2-buten-1-ol _{(CH 3 CH = C (CH} 3) -CH 2 -OH) , such as 2-20 carbons Alkoxy polyalkylene glycols (alcohol alkylene oxide adducts) (hereinafter also referred to as “unsaturated ethers”) obtained by adding 1 to 300 mol of alkylene oxide having 2 to 18 carbon atoms to unsaturated aliphatic alcohols. ), (2) methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol, 1-hexanol, octanol, 2-ethyl-1-hexanol, nonyl alcohol, lauryl alcohol, C1-C20 saturated aliphatic alcohols such as cetyl alcohol and stearyl alcohol Of alkoxypolyalkylene glycols (alcohol alkylene oxide adducts) obtained by adding 1 to 300 moles of alkylene oxide having 2 to 18 carbon atoms to unsaturated carboxylic acids such as (meth) acrylic acid and crotonic acid Esterified products (hereinafter also referred to as “unsaturated esters”) are preferred, and (1) 2-propen-1-ol (allyl alcohol) (CH ₂ ═CHCH ₂ —OH), 2-methyl-2-propene- 1- ol (methallyl _{alcohol) (CH 2 = C (CH} 3) -CH 2 -OH), 3- methyl-3-buten-1-ol _{(isoprenol) (CH 2 = C (CH} 3) -CH 2 CH ₂ -OH) unsaturated aliphatic alcohols having 3 to 5 carbon atoms 1 to 300 mols of alkylene oxide having 2 to 5 carbon atoms in such Alkoxypolyalkylene glycols (alcohol alkylene oxide adducts) (unsaturated ethers), (2) methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pen Alkoxypolyalkylene glycols (alcohol alkylene oxide adducts) obtained by adding 1 to 300 moles of alkylene oxides having 2 to 18 carbon atoms to saturated aliphatic alcohols having 1 to 5 carbon atoms such as tanol and (meth) Esterified products (unsaturated esters) with unsaturated carboxylic acids such as acrylic acid and crotonic acid are more preferred. (1) 2-methyl-2-propen-1-ol (methallyl alcohol) (CH ₂ ═C (CH ₃ ) —CH ₂ —OH), 3-methyl-3-buten-1-ol (isoprenol) _{) (CH 2 = C (CH} 3) -CH 2 CH 2 -OH) to alkoxy polyalkylene glycols obtained by 1-300 mols of alkylene oxide having 2 to 5 carbon atoms (alcohol alkylene oxide adducts) (Unsaturated ethers), (2) Carbon number in saturated aliphatic alcohols having 1 to 5 carbon atoms such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol and the like. Alkoxypolyalkylene glycols (a) obtained by adding 1 to 300 moles of 2 to 18 alkylene oxides. Call alkylene oxide adduct) and (meth) acrylic acid, esters of unsaturated carboxylic acids such as crotonic acid (unsaturated esters) are particularly preferred. These monomers (A) can be used alone or in combination of two or more. In addition, said unsaturated ester and unsaturated ether are arbitrary 1 type chosen from C2-C18 alkylene oxides, such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, as alkylene oxide, Alternatively, two or more alkylene oxides may be added. When two or more types are added, any of random addition, block addition, and alternate addition may be used.

  Accordingly, examples of the unsaturated polyalkylene glycol ether monomer (A) that can be used in the present invention may be those described above. For example, polyethylene glycol monovinyl ether, polyethylene glycol monoallyl ether, polyethylene glycol mono (2-methyl-2-propenyl) ether, polyethylene glycol mono (2-butenyl) ether, polyethylene glycol mono (3-methyl-3-butenyl) ether, polyethylene glycol mono (3-methyl-2-butenyl) ether, polyethylene Glycol mono (2-methyl-3-butenyl) ether, polyethylene glycol mono (2-methyl-2-butenyl) ether, polyethylene glycol mono (1,1-dimethyl-2-propenyl) ether, polyethylene Ethylene polypropylene glycol mono (3-methyl-3-butenyl) ether, methoxy polyethylene glycol mono (3-methyl-3-butenyl) ether, ethoxy polyethylene glycol mono (3-methyl-3-butenyl) ether, 1-propoxy polyethylene glycol Mono (3-methyl-3-butenyl) ether, cyclohexyloxypolyethyleneglycol mono (3-methyl-3-butenyl) ether, 1-octyloxypolyethyleneglycolmono (3-methyl-3-butenyl) ether, nonylalkoxypolyethyleneglycolmono (3-methyl-3-butenyl) ether, lauryl alkoxy polyethylene glycol mono (3-methyl-3-butenyl) ether, stearyl alkoxy polyethylene glycol (3-methyl-3-butenyl) ether, phenoxypolyethylene glycol mono (3-methyl-3-butenyl) ether, naphthoxypolyethylene glycol mono (3-methyl-3-butenyl) ether, methoxypolyethylene glycol monoallyl ether, Ethoxy polyethylene glycol monoallyl ether, phenoxy polyethylene glycol monoallyl ether, methoxy polyethylene glycol mono (2-methyl-2-propenyl) ether, ethoxy polyethylene glycol mono (2-methyl-2-propenyl) ether, phenoxy polyethylene glycol mono (2 -Methyl-2-propenyl) ether can be preferably used.

  In the present invention, the monomer (A) may be used alone or in the form of a mixture of two or more. The composition ratio of each monomer when the monomer (A) is used in the form of a mixture of two or more types can be appropriately selected according to the desired properties of the cement admixture to be produced, and is particularly limited is not. For example, a combination of monomers having different values of m in formula (1) can be suitably used. In this case, the composition ratio of each monomer is not particularly limited. For example, when used in the form of a mixture of two kinds, the composition ratio (mass ratio) of each monomer is 99. / 1-1 / 99, more preferably 80 / 20-20 / 80.

  The unsaturated organic acid monomer (B) used in the present invention may be any monomer having a polymerizable unsaturated group and a group capable of forming a carboxylic acid, and is represented by the following formula (2). It is a compound.

In the above formula (2), R ⁵ , R ⁶ and R ⁷ each independently represent a hydrogen atom, a methyl group, or — (CH ₂ ) _z COOM ² . In this case, — (CH ₂ ) _z COOM ² may form an anhydride with —COOM ¹ or other — (CH ₂ ) _z COOM ² , in which case M ¹ or M ² is not present. Z represents an integer of 0-2. Further, M ¹ and M ² each independently represent a hydrogen atom, an alkali metal atom, an alkaline earth metal atom, an ammonium group or an organic ammonium group. At this time, M ¹ and M ² may be the same or different. Here, examples of the alkali metal atom include lithium, sodium, potassium, and the like. Examples of alkaline earth metal atoms include calcium and magnesium. Among these, M ¹ and M ² are preferably a hydrogen atom, sodium, or potassium. The ammonium group is a functional group represented by “—NH ₄ ⁺ ”. Examples of the organic ammonium group include alkanolamines such as monoethanolamine, diethanolamine, and triethanolamine; alkylamines such as monoethylamine, diethylamine, and triethylamine; residues derived from organic amines such as polyamines such as ethylenediamine and triethylenediamine. Is mentioned.

Of the monomers (B) used in the present invention, unsaturated monocarboxylic acid monomers and unsaturated dicarboxylic acid monomers are preferably used, and unsaturated monocarboxylic acid monomers are More preferably used. Therefore, as the monomer (B) represented by the formula (2), an unsaturated monocarboxylic acid compound (that is, in the formula (2), R ⁵ , R ⁶ and R ⁷ are a hydrogen atom or a methyl group). Examples thereof include acrylic acid, methacrylic acid, crotonic acid and their metal salts, ammonium salts, organic ammonium salts, etc., and unsaturated dicarboxylic acid compounds (that is, R ⁵ , R ⁶ and R ^{7 in} formula (2)). Among them, maleic acid, itaconic acid, citraconic acid, fumaric acid, or a metal salt, ammonium salt, organic ammonium salt thereof, one of which represents — (CH ₂ ) _z COOM ² and the other represents a hydrogen atom or a methyl group) In addition, examples of these anhydrides include maleic anhydride, itaconic anhydride, citraconic anhydride, and the like. Of these, acrylic acid, methacrylic acid, maleic acid, maleic anhydride or salts thereof are preferable from the viewpoint of polymerizability, and acrylic acid or methacrylic acid is particularly preferable. In addition, only 1 type of these compounds may be used independently, and 2 or more types may be used together. Moreover, these compounds may use commercially available compounds, or may be prepared by synthesizing themselves.

  In addition to these, the monomer (B) includes a half ester of an unsaturated dicarboxylic acid monomer and an alcohol having 1 to 22 carbon atoms, an unsaturated dicarboxylic acid and an amine having 1 to 22 carbon atoms. And a half amide of an unsaturated dicarboxylic acid monomer and a glycol having 2 to 4 carbon atoms, and a half amide of maleamic acid and a glycol having 2 to 4 carbon atoms are used.

  In this invention, the said monomer (B) may be used individually by 1 type, or may be used with the form of a 2 or more types of mixture. The composition ratio of each monomer when the monomer (B) is used in the form of a mixture of two or more types can be appropriately selected according to the desired properties of the cement admixture to be produced, and is particularly limited is not. For example, acrylic monomers and methacrylic monomers, acrylic monomers and (anhydrous) maleic monomers, methacrylic monomers and (anhydrous) maleic monomers Combinations can be suitably used. In this case, the composition ratio of each monomer is not particularly limited. For example, when used in the form of a mixture of two kinds, the composition ratio (mass ratio) of each monomer is 99. / 1/1/99, more preferably 95/5 to 5/95, even more preferably 80/20 to 20/80. Thus, the unsaturated organic acid monomer (B) preferably includes a (meth) acrylic acid monomer, and particularly preferably includes an acrylic acid monomer. At this time, the ratio of the acrylic acid monomer is preferably 50% by mass or more of the mass of all monomers.

  The unsaturated carboxylic acid ester monomer (C) used in the present invention may be a carboxylic acid ester having a polymerizable unsaturated group, and is a compound represented by the following formula (3).

In the above formula (3), R ⁸ , R ⁹ and R ¹⁰ each independently represent a hydrogen atom, a methyl group, or — (CH ₂ ) _n COOR ¹² group, and n is an integer of 0-2. Represent. R ¹¹ and R ¹² represent an alkyl group having 1 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms, a hydroxyalkyl group having 1 to 20 carbon atoms, or an alkoxy group having 1 to 20 carbon atoms.

  Monomers (C) used in the present invention include alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and butyl (meth) acrylate. Esters; alkyl crotonates such as methyl crotonate, ethyl crotonate, propyl crotonate and butyl crotonate; hydroxyalkyl unsaturated carboxylic acid alkyl esters such as hydroxyethyl (meth) acrylate and hydroxyethyl crotonate; dimethyl maleate; And unsaturated carboxylic acid diesters such as diethyl maleate. Of these, from the viewpoint of solubility, methyl (meth) acrylate, ethyl (meth) acrylate, hydroxyethyl (meth) acrylate, and hydroxypropyl (meth) acrylate are preferably used. In addition, only 1 type of these compounds may be used independently, and 2 or more types may be used together. Moreover, these compounds may use commercially available compounds, or may be prepared by synthesizing themselves.

  The copolymer according to the present invention is produced by copolymerizing a monomer component containing the monomer (A), monomer (B) and monomer (C) as essential monomer components. However, it may further contain a fourth unsaturated monomer (X) (hereinafter also simply referred to as “monomer (X)”). In addition, the usage-amount of monomer (X) becomes like this. Preferably it is 0-70 mass% with respect to 100 mass% of whole quantity of a raw material compound (monomer), More preferably, it is 0-50 mass%, More preferably, it is 0-30 mass%, Most preferably, it is 0-10 mass%. The monomer (X) is not particularly limited as long as it is a compound copolymerizable with the above-described monomers (A), (B), and (C), and one or more of the following compounds may be used. Can be used.

  Half esters and diesters of unsaturated dicarboxylic acids such as maleic acid, maleic anhydride, fumaric acid, itaconic acid and citraconic acid and alcohols having 1 to 30 carbon atoms; the above unsaturated dicarboxylic acids and 1 to 30 carbon atoms Half-amides and diamides with amines: Half-esters and diesters of alkyl (poly) alkylene glycols obtained by adding 1 to 300 moles of an alkylene oxide having 2 to 18 carbon atoms to the alcohol or amine and the unsaturated dicarboxylic acids Half-esters and diesters of the above unsaturated dicarboxylic acids with glycols having 2 to 18 carbon atoms or polyalkylene glycols having 2 to 300 addition moles of these glycols; methyl (meth) acrylate, ethyl (meth) acrylate , Propyl (meth) acrylate, Esters of unsaturated monocarboxylic acids such as lysidyl (meth) acrylate, methyl crotonate, ethyl crotonate, propyl crotonate and alcohols having 1 to 30 carbon atoms; alcohols having 1 to 30 carbon atoms and carbon atoms Esters of alkoxy (poly) alkylene glycols to which 1 to 300 moles of alkylene oxide of 2 to 18 are added and unsaturated monocarboxylic acids such as (meth) acrylic acid; (poly) ethylene glycol monomethacrylate, (poly) propylene 1-300 molar adducts of alkylene oxides having 2 to 18 carbon atoms to unsaturated monocarboxylic acids such as (meth) acrylic acid, such as glycol monomethacrylate and (poly) butylene glycol monomethacrylate; maleamic acid and carbon Glycols having 2 to 18 atoms or Half amides of polyalkylene glycols of addition mole number 2 to 300 of these glycols.

  (Poly) alkylene glycols such as triethylene glycol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, (poly) ethylene glycol (poly) propylene glycol di (meth) acrylate, etc. Di (meth) acrylates; polyfunctional (meth) acrylates such as hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane di (meth) acrylate; triethylene glycol dimaleate, polyethylene glycol (Poly) alkylene glycol dimaleates such as dimaleate; vinyl sulfonate, (meth) allyl sulfonate, 2- (meth) acryloxyethyl sulfonate, 3- (meth) acrylate Xylpropyl sulfonate, 3- (meth) acryloxy-2-hydroxypropyl sulfonate, 3- (meth) acryloxy-2-hydroxypropylsulfophenyl ether, 3- (meth) acryloxy-2-hydroxypropyloxysulfobenzoate, 4- ( Unsaturated sulfonic acids such as (meth) acryloxybutyl sulfonate, (meth) acrylamide methyl sulfonic acid, (meth) acrylamide ethyl sulfonic acid, 2-methylpropane sulfonic acid (meth) acrylamide, styrene sulfonic acid, and monovalents thereof Metal salts, divalent metal salts, ammonium salts and organic ammonium salts; Amides of unsaturated monocarboxylic acids and amines having 1 to 30 carbon atoms such as methyl (meth) acrylamide; Styrene, α-methylstyrene, vinyl Vinyl aromatics such as toluene, p-methylstyrene; 1,4-butanediol mono (meth) acrylate, 1,5-pentanediol mono (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, etc. Alkanediol mono (meth) acrylates; dienes such as butadiene, isoprene, 2-methyl-1,3-butadiene, 2-chloro-1,3-butadiene and the like.

  Unsaturated amides such as (meth) acrylamide, (meth) acrylalkylamide, N-methylol (meth) acrylamide, N, N-dimethyl (meth) acrylamide; unsaturated cyanides such as (meth) acrylonitrile and α-chloroacrylonitrile Unsaturated esters such as vinyl acetate and vinyl propionate; aminoethyl (meth) acrylate, methylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, Unsaturated amines such as dibutylaminoethyl acrylate and vinyl pyridine; divinyl aromatics such as divinylbenzene; cyanurates such as triallyl cyanurate; (meth) allyl alcohol, glycidyl (meth) allyl ether, etc. Allyls; Methoxypoly Tylene glycol monovinyl ether, polyethylene glycol monovinyl ether, methoxypolyethylene glycol mono (meth) allyl ether, polyethylene glycol mono (meth) allyl ether, and other vinyl ethers or allyl ethers; polydimethylsiloxanepropylaminomaleamic acid, polydimethylsiloxaneamino Propyleneaminomaleamic acid, polydimethylsiloxane-bis- (propylaminomaleamic acid), polydimethylsiloxane-bis- (dipropyleneaminomaleamic acid), polydimethylsiloxane- (1-propyl-3-acrylate), poly Dimethylsiloxane- (1-propyl-3-methacrylate), polydimethylsiloxane-bis- (1-propyl-3-acrylate) ), Siloxane derivatives such as polydimethylsiloxane-bis- (1-propyl-3-methacrylate).

  In the method for producing a copolymer according to the present invention, a polymerization initiator (D) is preferably used in the copolymerization. The polymerization initiator (D) used in the present invention is preferably a radical polymerization initiator. For example, in the case of performing aqueous solution polymerization, persulfates such as ammonium persulfate, sodium persulfate, potassium persulfate, hydrogen peroxide, etc. Peroxides; azoamidine compounds such as 2,2′-azobis-2-methylpropionamidine hydrochloride; cyclic azoamidine compounds such as 2,2′-azobis-2- (2-imidazolin-2-yl) propane hydrochloride Azo initiators such as 2-carbamoylazoisobutyronitrile; and the like, for example, solution polymerization or bulk polymerization using a lower alcohol, aromatic or aliphatic hydrocarbon, ester compound, ketone compound or the like as a solvent. When performing, benzoyl peroxide, lauroyl peroxide, sodium peroxide, t-butyl hydroperoxide Oxides, peroxides such as cumene hydroperoxide; azo initiators such as azobisisobutyronitrile; and the like. Furthermore, when a water-lower alcohol mixed solvent is used, it can be appropriately selected from the above-mentioned various radical polymerization initiators. The bulk polymerization is performed within a temperature range of 50 to 200 ° C. The polymerization initiator (D) may be used alone or in the form of a mixture of two or more.

  In the method for producing a copolymer according to the present invention, a reducing agent (E) is preferably used in the copolymerization. In the present invention, when the reducing agent is used in combination with the above-described peroxide, polymerization can be initiated as a redox polymerization initiator.

Examples of the reducing agent (E) used in the present invention include iron (II), tin (II), titanium (III), chromium (II), V (II), and Cu (II) as represented by the mole salt. Metal salts in the low valence state such as monoethanolamine, diethanolamine, triethanolamine, hydroxylamine, hydroxylamine hydrochloride, hydrazine and other amine compounds and salts thereof; sodium dithionite, sodium formaldehyde sulfoxylate In addition to sodium hydroxymethanesulfinate dihydrate and the like, organic compounds containing a group such as —SH, —SO ₂ H, —NHNH ₂ , —COCH (OH) — and salts thereof; sodium sulfite, sodium bisulfite, Alkali metal sulfites such as metabisulfite, hypophosphorous acid, sodium hypophosphite Lower oxides such as sodium hydrosulfite and sodium hyponitrite and salts thereof; invert sugars such as D-fructose and D-glucose; thiourea compounds such as thiourea and thiourea dioxide; L-ascorbic acid (salt) and L-ascorbine Acid ester, erythorbic acid (salt), erythorbic acid ester and the like can be mentioned. Among these, L-ascorbic acid, L-ascorbic acid ester, and erythorbic acid (salt) are preferable from the viewpoint of solubility.

  Specific examples of the combination of the polymerization initiator (D) and the reducing agent (E) used in the present invention include, for example, a combination of benzoyl peroxide and an amine, cumene hydroperoxide, iron (II), Cu (II ) And other metal compounds. Among them, a combination of a water-soluble peracid peroxide and a reducing agent is particularly preferable. For example, a combination of hydrogen peroxide and L-ascorbic acid, a combination of hydrogen peroxide and erythorbic acid, hydrogen peroxide and a mol salt, The combination of sodium persulfate and sodium hydrogen sulfite is particularly preferred. A particularly preferred combination is a combination of hydrogen peroxide and L-ascorbic acid.

  In the method for producing a copolymer according to the present invention, it is preferable to use a chain transfer agent (F) during the copolymerization. By using a chain transfer agent during the copolymerization, the molecular weight of the resulting copolymer can be easily adjusted. In particular, when the polymerization reaction is performed at a high concentration of 30% by mass or more based on the total amount of raw materials used at the time of polymerization, the above effect is remarkable by using a chain transfer agent. .

  The chain transfer agent (F) used in the present invention is not particularly limited as long as it is a compound capable of adjusting the molecular weight of the copolymer, and a known chain transfer agent can be used. Specifically, mercaptoethanol, thioglycerol, thioglycolic acid, mercaptopropionic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiomalic acid, octyl thioglycolate, octyl 3-mercaptopropionate, 2-mercaptoethane Thiol chain transfer agents such as sulfonic acid, n-dodecyl mercaptan, octyl mercaptan, butyl thioglycolate; halides such as carbon tetrachloride, carbon tetrabromide, methylene chloride, bromoform, bromotrichloroethane; α-methylstyrene dimer, Unsaturated hydrocarbon compounds such as α-terpinene, γ-terpinene, dipentene, terpinolene, etc. Primary alcohols such as 2-aminopropan-1-ol; Secondary alcohols such as isopropanol; Phosphorous acid, hypophosphorous acid, And its salts (sodium hypophosphite, potassium hypophosphite, etc.), sulfurous acid, hydrogen sulfite, dithionite, metabisulfite, and salts thereof (sodium sulfite, potassium sulfite, sodium hydrogen sulfite, potassium hydrogen sulfite, Lower dioxide of sodium dithionite, potassium dithionite, sodium metabisulfite, potassium metabisulfite, etc.) and their salts. Moreover, you may use a monomer with high chain transfer property as a chain transfer agent. Among these, mercaptopropionic acid, 2-mercaptopropionic acid, and 3-mercaptopropionic acid are preferable from the viewpoint of solubility. The chain transfer agent (F) may be used alone or in a mixture of two or more.

  The copolymerization method of the monomers (A), (B) and (C) and, if necessary, the monomer (X) is not particularly limited, and a known copolymerization method can be used. Hereinafter, preferred embodiments of the copolymerization method of the monomers (A), (B) and (C) according to the present invention will be described.

  As described above, in the present invention, each monomer (polymerization component) and the component involved in the polymerization reaction (polymerization initiator (D)) when the monomers (A), (B) and (C) are copolymerized. , Reducing agent (E), and chain transfer agent (F)) are added to the reaction vessel as unsaturated organic acid monomer (B), unsaturated carboxylic acid ester monomer (C), At least two components selected from the group consisting of a polymerization initiator (D), a reducing agent (E), and a chain transfer agent (F) are added to the reaction vessel while changing the addition rate at least once. preferable. At this time, the monomer (A) may be added to the reaction vessel all at once before the copolymerization reaction, or when adding at least one of the addition rate changing components. You may add together. Thus, by adding the addition rate of the addition rate changing component at least once during the polymerization step, the copolymerization reaction of the monomers (A), (B) and (C) can be efficiently performed. A copolymer with a more uniform monomer composition or two or more copolymer blends with different monomer compositions can be produced in one polymerization step, and the rate of addition can be changed. By appropriately adjusting the degree, it is possible to obtain copolymers having different characteristics such as excellent water-reducing performance and / or excellent slump retention, so that at least two of the addition rate changing components By appropriately changing the addition rate, a cement admixture copolymer having desired characteristics can be produced in one polymerization step.

  First, a method for adding components used in the production method of the present invention to a reaction vessel will be described below.

  In the present invention, as a method for adding the monomer (A) to the reaction vessel, the monomer (A) may be added to the reaction vessel all at once, may be added dropwise or divided, or continuously in the reaction system. The addition speed may be changed while adding continuously. In addition, the monomer (A) may be added to the reaction vessel alone or in advance with another monomer (B) and / or monomer (C) constituting the monomer component, a solvent, etc. It may be mixed.

  One form of the present invention is a production method in which y in the above formula (1) is 0 and the unsaturated polyalkylene glycol ether monomer (A) is added to the reaction vessel in advance.

  That is, when the monomer (A) is an unsaturated ether (alkoxy polyalkylene glycol (alcohol alkylene oxide adduct) obtained by adding an alkylene oxide having 2 or more carbon atoms to an unsaturated aliphatic alcohol) First, the monomer (A) having low reactivity (polymerizability) is added all at once, that is, after the monomer (A) is previously added to the reaction vessel, at least two of the addition rate changing components are added. By adding one component, the copolymerization reaction of the monomers (A), (B), and (C) can be efficiently performed, and the above-described effects are more remarkable, which is preferable.

  In another embodiment of the present invention, y in the formula (1) is 1, and the unsaturated polyalkylene glycol ether monomer (A) is an unsaturated organic acid monomer (B). And an unsaturated carboxylic acid ester monomer (C).

  That is, the monomer (A) is an unsaturated ester (an alkoxypolyalkylene glycol (alcohol alkylene oxide adduct) obtained by adding an alkylene oxide having 2 or more carbon atoms to a saturated aliphatic alcohol) and an unsaturated carboxylic acid. In the case of an esterified product with an acid), the monomer (A), the monomer (B) and the monomer (C) are added at the same time, whereby the monomers (A), (B) and (C) This is preferable because the above copolymerization reaction can be carried out efficiently and the above-mentioned effects are more remarkable. “Monomer (A), monomer (B) and monomer (C) are added simultaneously” means that monomer (A), monomer (B) and monomer (C ) Are added to the reaction vessel in advance, a solution containing the monomer (A), a solution containing the monomer (B), and a solution containing the monomer (C) are prepared, and the solutions are reacted simultaneously. It may be added to the container all at once, or may be continuously dropped, or the monomer (A), monomer (B) and monomer (C) as a single solution, all at once in the reaction container. It may be added or continuously dropped. Of these, continuous dripping is preferable because it suppresses an increase in reaction temperature. Moreover, when adding a monomer (A), a monomer (B), and a monomer (C) simultaneously, it is preferable to also add a chain transfer agent (F) simultaneously because prescription becomes simple.

  In the present invention, as a method for adding the monomer (B) to the reaction vessel, the monomer (B) may be added all at once to the reaction vessel, may be added dropwise, divided, or continuously in the reaction system. The addition rate may be changed continuously, or the addition rate may be changed while continuously adding, but the addition rate may be dropped and continuously added to the reaction system, or the addition rate may be changed while continuously added. Is preferable. In addition, the monomer (B) may be added to the reaction vessel alone or in advance with another monomer (A) and / or monomer (C) constituting the monomer component, a solvent, etc. It may be mixed.

  In the present invention, as a method for adding the monomer (C) to the reaction vessel, the monomer (C) may be added to the reaction vessel all at once, may be added dropwise or divided, or continuously in the reaction system. The addition rate may be changed continuously, or the addition rate may be changed while continuously adding, but the addition rate may be dropped and continuously added to the reaction system, or the addition rate may be changed while continuously added. Is preferable. In addition, the monomer (B) may be added to the reaction vessel alone or in advance with another monomer (A) and / or monomer (B) constituting the monomer component, a solvent, etc. It may be mixed.

  In the present invention, as a method for adding the polymerization initiator (D) to the reaction vessel, the polymerization initiator (D) may be added all at once to the reaction vessel, or may be added dropwise, divided, or continuously in the reaction system. The addition speed may be changed while adding continuously. Further, the polymerization initiator (D) may be added alone to the reaction vessel, or may be mixed in advance with another monomer (A), (B) or (C) constituting the monomer component, a solvent or the like. May be.

  In the present invention, as a method for adding the reducing agent (E) to the reaction vessel, the reducing agent (E) may be added all at once to the reaction vessel, or may be added dropwise or divided, or continuously in the reaction system. The addition rate may be changed while continuously adding. It may be added to the reaction vessel all at once, or may be added dropwise or divided. Further, the reducing agent (E) may be added alone to the reaction vessel, or may be another monomer (A), (B) and / or (C) constituting a monomer component, a chain transfer agent ( F) may be premixed with a solvent or the like.

  In the copolymerization, it is preferable that at least one of the polymerization initiator (D) and the reducing agent (E) is always present in the reaction system. Specifically, the polymerization initiator (D) and the reducing agent (E) need not be added all at once. For example, the polymerization initiator (D) and the reducing agent (E) may be added over a long period of time, for example, by adding them both continuously or in divided portions. do it. When the polymerization initiator (D) and the reducing agent (E) are added simultaneously, since the polymerization initiator (D) and the reducing agent (E) react rapidly, a large amount of reaction heat occurs immediately after the addition. It becomes difficult to control the reaction, and the radical concentration rapidly decreases thereafter, so that a large amount of unreacted monomer remains. Furthermore, since the radical concentration with respect to the monomer is extremely different between the initial stage and the latter half of the reaction, the molecular weight distribution becomes extremely large, and the performance as a cement admixture decreases. The time from the addition of one to the start of the addition of the other is preferably within 5 hours, particularly preferably within 3 hours.

  In the present invention, as a method of adding the chain transfer agent (F) to the reaction vessel, it may be added all at once to the reaction vessel, may be added dropwise, divided, or continuously in the reaction system. The addition speed may be changed while adding continuously. Further, the chain transfer agent (F) may be added alone to the reaction vessel, or may be another monomer (A), (B) and / or (C) constituting the monomer component, a reducing agent ( E) may be mixed in advance with a solvent or the like.

  In addition, when the monomer (X) is used, the addition time of the monomer (X) is determined by efficiently copolymerizing with the monomers (A), (B) and (C) to obtain the desired copolymer weight. There is no particular limitation as long as the blended blend can be produced, even if it is previously added to the reaction vessel; it may be added together with the monomer (A); the monomer (B) and / or the monomer ( C) may be added continuously or stepwise (there may be times when monomer (X) is not added); or monomer (B) and / or monomer It may be added after the addition of (C) is completed. Of these, the monomer (X) is preferably added dropwise.

  Next, a specific method for changing the addition rate of the addition rate changing component in the production method of the present invention will be described.

The degree of changing the addition rate of the addition rate changing component between stages is not particularly limited, and the desired properties of the cement admixture to be produced (particularly, the balance between improvement in water reduction performance and water reduction performance or slump retention). ) And monomers (A), (B) and (C) can be appropriately selected in consideration of the copolymerization property, but the structure of the copolymer due to change in the addition rate of the addition rate change component between steps (single amount) In consideration of changes in body composition, it is preferably at a certain ratio or more. That is, when continuously changing the addition rate of the addition rate change component, the addition amount of the addition rate change component per hour, that is, the maximum value (V _MAX ) and the minimum value of the addition rate (parts by mass / min) _{(V MIN)} ratio _(V MAX _/ V _MIN) is preferably 1.2 times or more, more preferably 1.25 to 30 times, even more preferably 1.5 to 15 times, and most preferably 1.8 ~ 5 times.

In addition, when the addition rate of the addition rate changing component to the monomer (A) is changed stepwise to increase the addition rate in the first half compared to the addition rate in the second half, the addition rate of the addition rate change component in the first half Is V _P1, and the addition rate in the latter half is V _P2 , the ratio (V _P1 / V _P2 ) of the addition rate change component before and after the change of the addition rate is preferably 1.02 times or more, more preferably 1 0.05 to 30 times, even more preferably 1.06 to 15 times, and most preferably 1.07 to 5 times. At this time, if the ratio of V _P1 / V _P2 is less than 1.02, the change in the addition rate of the addition rate changing component between steps is too small, and the copolymer structure (monomer composition) is significantly increased. Therefore, even if the copolymer obtained by such a method is used as a cement admixture, the desired water-reducing performance cannot be improved and the cement can be obtained to achieve the desired effect. Large amounts of admixture may be required. Moreover, as the ratio before and after the change of the addition rate of each component of the addition rate change component, the ratio (V _B1 / V _B2 ) before and after the change of the monomer (B) is preferably 1.2 times or more, more Preferably it is 1.25 to 30 times, even more preferably 1.3 to 15 times, most preferably 1.5 to 5 times, and the ratio (V _C1 / V _C2 ) before and after the change of the monomer (C) Is preferably 1.2 times or more, more preferably 1.25 to 30 times, even more preferably 1.3 to 15 times, and most preferably 1.5 to 5 times, and the polymerization initiator (D) The ratio (V _D1 / V _D2 ) before and after the change is preferably 1.2 times or more, more preferably 1.25 to 30 times, still more preferably 1.3 to 15 times, and most preferably 1.5 to 5 times. The ratio before and after the change of the reducing agent (E) (V _E1 / V _E2 ) is preferably 1.02 times or more, more preferably 1.05 to 30 times, even more preferably 1.06 to 15 times, and most preferably 1.07 to 5, and the ratio before and after the change of the chain transfer agent (F) ( V _F1 / V _F2 ) is preferably 1.02 times or more, more preferably 1.05 to 30 times, still more preferably 1.06 to 15 times, and most preferably 1.07 to 5.

In addition, when the addition rate of the addition rate changing component is changed stepwise, and the addition rate in the latter half is made higher than the addition rate in the first half, the addition rate of the addition rate changing component in the first half is set to V _P1. When the addition rate of V _P2 is V _P2 , the ratio (V _P2 / V _P1 ) of the addition rate change component before and after the change in the addition rate is preferably 1.02 times or more, more preferably 1.05 to 30 times, even more Preferably it is 1.06-15 times, Most preferably, it is 1.07-5 times. At this time, when the ratio of V _P2 / V _P1 is less than 1.02, the change in the addition rate of the addition rate change component between the steps is too small as described above, and the copolymer structure (monomer composition Therefore, even if the copolymer obtained by such a method is used as a cement admixture, the desired improvement in slump retention cannot be achieved, and the workability with time is improved. May get worse. Moreover, as the ratio before and after the change of the addition rate of each component of the addition rate change component, the ratio (V _B2 / V _B1 ) before and after the change of the monomer (B) is preferably 1.2 times or more, more Preferably it is 1.25 to 30 times, even more preferably 1.3 to 15 times, most preferably 1.5 to 5 times, and the ratio (V _C2 / V _C1 ) before and after the change of the monomer (C) Is preferably 1.02 times or more, more preferably 1.05 to 30 times, even more preferably 1.06 to 15 times, most preferably 1.07 to 5, and the change of the polymerization initiator (D) The front / rear ratio (V _D2 / V _D1 ) is preferably 1.02 times or more, more preferably 1.05 to 30 times, still more preferably 1.06 to 15 times, and most preferably 1.07 to 5. Yes, the ratio (V _E1 / V _E2 ) before and after the change of the reducing agent (E) is favorable. It is preferably 1.2 times or more, more preferably 1.25 to 30 times, even more preferably 1.5 to 15 times, most preferably 2 to 5, and the ratio before and after the change of the chain transfer agent (F). (V _F2 / V _F1 ) is preferably 1.02 times or more, more preferably 1.05 to 30 times, still more preferably 1.06 to 15 times, and most preferably 1.07 to 5.

  In the present invention, even in an embodiment in which the addition rate of the addition rate changing component is changed in three or more steps in one polymerization step, the degree of change of the addition rate of the addition rate changing component between the steps is within the above range. Preferably there is.

  In the present invention, the addition condition of the addition rate changing component is not particularly limited as long as desired characteristics (water reduction performance and slump retention) are obtained. For example, the addition rate of the addition rate changing component can be appropriately selected depending on the amount of the monomer (A) and desired characteristics. Hereinafter, although described as an addition rate with respect to the monomer (A), the amount of the monomer (A) means the total amount added to the reaction system.

  For example, when the addition rate changing component is added in two steps, the addition rate of the monomer (B) at a low rate is preferably 0.1 with respect to 100 parts by mass of the monomer (A). -20 parts by mass / hour, more preferably 0.5-5 parts by mass / hour. In such a case, the addition rate of the monomer (B) in the early stage is preferably 0.5 to 50 parts by mass / hour, more preferably 100 parts by mass of the monomer (A). Is 1-15 parts by mass / hour. The addition time of the monomer (B) can be appropriately selected depending on the addition amount of the monomers (A), (B) and (C) and desired properties as a cement admixture. -10 hours, more preferably 1-6 hours. The addition temperature of the monomer (B) may be the same as the polymerization temperature described in detail below, but is preferably 0 to 150 ° C, more preferably 30 to 100 ° C, most preferably 40 to 80. ° C.

  In addition, when the addition rate changing component is added in two steps, the addition rate of the monomer (C) at a low rate is preferably 0.1 with respect to 100 parts by mass of the monomer (A). -20 parts by mass / hour, more preferably 0.5-5 parts by mass / hour. In such a case, the addition rate of the monomer (C) in the early stage is preferably 0.5 to 50 parts by mass / hour, more preferably 100 parts by mass of the monomer (A). Is 1-15 parts by mass / hour. The addition time of the monomer (C) can be appropriately selected depending on the addition amount of the monomers (A), (B) and (C) and desired properties as a cement admixture. -10 hours, more preferably 1-6 hours. The addition temperature of the monomer (C) may be the same as the polymerization temperature described in detail below, but is preferably 0 to 150 ° C, more preferably 30 to 100 ° C, most preferably 40 to 80. ° C.

  In addition, when the addition rate changing component is added in two steps, the addition rate of the polymerization initiator (D) at a low rate is preferably 0.001 with respect to 100 parts by mass of the monomer (A). -20 parts by mass / hour, more preferably 0.005-5 parts by mass / hour. In such a case, the addition rate of the polymerization initiator (D) in the early stage is preferably 0.005 to 50 parts by mass / hour, more preferably 100 parts by mass of the monomer (A). Is 0.01 to 15 parts by mass / hour. The addition time of the polymerization initiator (D) can be appropriately selected depending on the addition amount of the monomers (A), (B) and (C) and desired properties as a cement admixture. -10 hours, more preferably 1-6 hours. Further, the addition temperature of the polymerization initiator (D) may be the same as the polymerization temperature described in detail below, but is preferably 0 to 150 ° C, more preferably 30 to 100 ° C, and most preferably 40 to 80. ° C.

  In addition, when the addition rate changing component is added in two steps, the addition rate of the reducing agent (E) at a low rate is preferably 0.001 to 100 parts by mass of the monomer (A). 20 parts by mass / hour, more preferably 0.005 to 5 parts by mass / hour. Moreover, in such a case, the addition rate of the reducing agent (E) in the early stage is preferably 0.01 to 50 parts by mass / hour, more preferably 100 parts by mass of the monomer (A). 0.02 to 15 parts by mass / hour. Further, the addition time of the reducing agent (E) can be appropriately selected depending on the addition amount of the monomers (A), (B) and (C) and desired properties as a cement admixture, but preferably 0.5 to 10 hours, more preferably 1 to 6 hours. The addition temperature of the reducing agent (E) may be the same as the polymerization temperature described in detail below, but is preferably 0 to 150 ° C, more preferably 30 to 100 ° C, and most preferably 40 to 80 ° C. It is.

  In addition, when the addition rate changing component is added in two stages, the addition rate of the chain transfer agent (F) at a slow stage is preferably 0.01 with respect to 100 parts by mass of the monomer (A). -20 mass parts / hour, more preferably 0.025-5 mass parts / hour. In such a case, the addition rate of the chain transfer agent (F) in the early stage is preferably 0.01 to 50 parts by mass / hour, more preferably 100 parts by mass of the monomer (A). Is 0.05 to 15 parts by mass / hour. Further, the addition time of the chain transfer agent (F) can be appropriately selected depending on the addition amount of the monomers (A), (B) and (C) and desired properties as a cement admixture, but preferably 0.5 -10 hours, more preferably 1-6 hours. The addition temperature of the chain transfer agent (F) may be the same as the polymerization temperature as described in detail below, but is preferably 0 to 150 ° C, more preferably 30 to 100 ° C, and most preferably 40 to 80. ° C.

  Next, a specific combination for changing the addition rate of the addition rate changing component will be described.

  In the present invention, when the addition rate of the addition rate changing component is increased at a later stage, a copolymer blend having a moderately different monomer composition ratio in the mixture can be produced. Depending on the composition, the slump retainability is particularly excellent.

  In the case where the addition rate of the addition rate changing component is increased at a later stage, a preferable combination of the addition rate changing components for changing the addition rate (hereinafter, the combination is expressed as “component-component”) is the monomer (B). -Monomer (C) combination, monomer (B)-polymerization initiator (D) combination, monomer (B)-reducing agent (E) combination, monomer (B)-chain transfer Agent (F) combination, monomer (C) -initiator (D) combination, monomer (C) -reducing agent (E) combination, monomer (C) -chain transfer agent (F ), Polymerization initiator (D) -reducing agent (E) combination, polymerization initiator (D) -chain transfer agent (F) combination, reducing agent (E) -chain transfer agent (F) combination Combination of two components; monomer (B) -monomer (C) -polymerization initiator (D) combination Monomer (B) -monomer (C) -reducing agent (E) combination, monomer (B) -monomer (C) -chain transfer agent (F) combination, monomer (B) -polymerization initiator (D) -reducing agent (E) combination, monomer (B) -polymerization initiator (D) -chain transfer agent (F) combination, monomer (B) -reduction Agent (E) -chain transfer agent (F) combination, monomer (C) -polymerization initiator (D) -reducing agent (E) combination, monomer (C) -polymerization initiator (D)- Combination of chain transfer agent (F), monomer (C) -reducing agent (E) -chain transfer agent (F), polymerization initiator (D) -reducing agent (E) -chain transfer agent (F) A combination of the following three components: monomer (B) -monomer (C) -polymerization initiator (D) -reducing agent (E) combination, monomer (B) -monomer (C) -Polymerization initiator A combination of four components of a combination of D) -chain transfer agent (F), monomer (B) -monomer (C) -reducing agent (E) -chain transfer agent (F); B) -monomer (C) -polymerization initiator (D) -reducing agent (E) -chain transfer agent (F) in combination of five components; among these, more preferably a single amount The combination of a form (B) -monomer (C), the combination of a monomer (B) -chain transfer agent (F), and the combination of a monomer (C) -reducing agent (E).

  In the present invention, when the addition rate of the addition rate changing component is slowed in a later stage, a copolymer having a more uniform monomer composition ratio in the mixture can be produced, and this copolymer has a single monomer composition. As a result, the water reduction performance is particularly excellent.

  In the case where the addition rate of the addition rate changing component is slowed down in a later stage, a preferable combination of the addition rate changing component for changing the addition rate includes a monomer (B) -monomer (C) combination, a monomer ( B) -polymerization initiator (D) combination, monomer (B) -reducing agent (E) combination, monomer (B) -chain transfer agent (F) combination, monomer (C)- Combination of polymerization initiator (D), monomer (C) -reducing agent (E), monomer (C) -chain transfer agent (F), polymerization initiator (D) -reducing agent ( E), polymerization initiator (D) -chain transfer agent (F) combination, reducing agent (E) -chain transfer agent (F) combination, monomer (B) -monomer (C)- Combination of polymerization initiator (D), monomer (B) -monomer (C) -reducing agent (E), monomer B) -monomer (C) -chain transfer agent (F) combination, monomer (B) -polymerization initiator (D) -reducing agent (E) combination, monomer (B) -polymerization start Agent (D)-Chain Transfer Agent (F) Combination, Monomer (B)-Reducing Agent (E)-Chain Transfer Agent (F) Combination, Monomer (C)-Polymerization Initiator (D)- Combination of reducing agent (E), monomer (C) -polymerization initiator (D) -chain transfer agent (F), monomer (C) -reducing agent (E) -chain transfer agent (F) A combination of three components: a combination of polymerization initiator (D) -reducing agent (E) -chain transfer agent (F); monomer (B) -monomer (C) -polymerization initiator (D) -Reducing agent (E) combination, monomer (B)-monomer (C)-polymerization initiator (D)-chain transfer agent (F) combination, monomer (B)-monomer ( C)- Combination of four components of a combination of the base agent (E) -chain transfer agent (F); monomer (B) -monomer (C) -polymerization initiator (D) -reducing agent (E) -chain transfer agent Among these, the combination of monomer (B) -monomer (C), monomer (B) -polymerization initiator (D ), Monomer (C) -chain transfer agent (F) combination, polymerization initiator (D) -reducing agent (E) combination, reducing agent (E) -chain transfer agent (F) combination, It is a combination of monomer (B) -monomer (C) -reducing agent (E) -chain transfer agent (F).

  Furthermore, in the present invention, when the addition rate is changed using a component that increases the addition rate of the addition rate change component in a later stage and a component that decreases the addition rate of the addition rate change component in a later stage, etc. The desired composition can be achieved by various combinations.

  Furthermore, when the addition rate is changed using a component that increases the addition rate of the addition rate changing component in a later step and a component that decreases the addition rate of the addition rate change component in a later step, a preferable addition rate changing component As a combination (hereinafter referred to as “component that accelerates in later stage-component that slows in later stage”), monomer (B) -monomer (C) combination, monomer (C) -single Combination of monomer (B), monomer (B) -polymerization initiator (D), polymerization initiator (D) -monomer (B), monomer (B) -reducing agent ( E), reducing agent (E) -monomer (B) combination, monomer (B) -chain transfer agent (F) combination, chain transfer agent (F) -monomer (B) Combination, monomer (C) -polymerization initiator (D) combination, polymerization initiator (D) -monomer C), monomer (C) -reducing agent (E) combination, reducing agent (E) -monomer (C) combination, monomer (C) -chain transfer agent (F) combination , A combination of polymerization initiator (D) -reducing agent (E), a combination of polymerization initiator (D) -chain transfer agent (F), and a combination of reducing agent (E) -chain transfer agent (F). Of these, the combination of monomer (B) and polymerization initiator (D) is more preferable.

  In the method for producing a copolymer according to the present invention, the monomers (A), (B) and (C), and, if necessary, the monomer (X) are copolymerized. In this case, the copolymerization method is not particularly limited, and known methods such as solution polymerization and bulk polymerization can be used. The copolymerization can be carried out either batchwise or continuously. The solvent used in this case is water; alcohol such as methyl alcohol, ethyl alcohol, isopropyl alcohol; benzene, toluene, xylene, cyclohexane, n -Aromatic or aliphatic hydrocarbons such as hexane; ester compounds such as ethyl acetate; ketone compounds such as acetone and methyl ethyl ketone; cyclic ether compounds such as tetrahydrofuran and dioxane. In addition, the said solvent may be used independently or may be used with the form of a 2 or more types of liquid mixture. Among these, it is preferable to use at least one selected from the group consisting of water and lower alcohols having 1 to 4 carbon atoms. Since the desolvation step can be omitted, it is particularly preferable to use water. The amount of the solvent used is not limited as long as the copolymerization of the monomers (A), (B) and (C), and the monomer (X) can proceed sufficiently if necessary. The amount of solvent is preferably adjusted so that the amount of all monomer components used in the polymerization is 30% by mass or more based on the mass of all raw materials including other raw materials. More preferably, the amount of all monomer components used in the copolymerization is 30 to 95% by mass, even more preferably 40 to 93% by mass, based on the mass of all raw materials including other raw materials. The amount of the solvent is adjusted so that it is most preferably 50 to 90% by mass. At this time, when the amount of all the monomer components used is less than 30% by mass, the polymerization rate may decrease or the productivity may decrease.

  In the method for producing a copolymer according to the present invention, the polymerization of the monomer component may be performed in the presence of a pH adjuster while controlling the pH during the polymerization to 3 or less (preferably pH = 2 to 3). it can. Sufficient copolymerization of unsaturated polyalkylene glycol ether monomers can be easily expressed by performing polymerization of the above monomer components in the presence of a pH adjuster while controlling the pH during polymerization to 3 or less. Thus, the production cost of the polycarboxylic acid copolymer to be produced can be reduced, and a polycarboxylic acid copolymer that can provide an unprecedented high-performance cement admixture can be produced.

  Examples of the pH adjuster include phosphoric acid and / or a salt thereof, organic sulfonic acid and / or a salt thereof, hydrochloric acid and / or a salt thereof, nitric acid and / or a salt thereof, sulfuric acid and / or a salt thereof. Among these, at least one selected from phosphoric acid and / or a salt thereof and organic sulfonic acid and / or a salt thereof is preferable, and an organic sulfonic acid and / or a salt thereof is more preferable in that the addition amount can be reduced. Any appropriate salt can be adopted as the salt. Examples thereof include alkali metal salts, alkaline earth metal salts, ammonium salts, and organic ammonium salts. Only 1 type of pH adjuster may be used and it may use 2 or more types together. Specific examples of the organic sulfonic acid and / or salt thereof include p-toluenesulfonic acid and / or a hydrate thereof, methanesulfonic acid and / or a salt thereof, and the like. The amount of the pH adjuster used is preferably 0.01 to 5% by mass, more preferably 0.05 to 4% by mass, and still more preferably 0.05 to 2.5% by mass, based on the total amount of the monomer components. %. If the amount of the pH adjusting agent used is too large, the pH during the polymerization will be too low, which may result in inappropriate polymerization conditions.

  In the method for producing a copolymer according to the present invention, the pH is preferably adjusted to 5 or more after copolymerization. In the present invention, the copolymer obtained by copolymerization is preferably adjusted to pH 5 or more, more preferably pH 5 to 7.5, and further preferably pH 5 to 7 from the viewpoint of handleability. When the polymerization is carried out at a pH of 5 or more, the polymerization rate is lowered, and at the same time, the copolymerizability is deteriorated, and the dispersion performance is lowered as a copolymer for cement admixture. Although it is preferable to adjust the pH to 5 or more after polymerization, it is also possible to adjust the pH range to 4 to 5 by partial neutralization. Adjustment of pH is performed by, for example, inorganic salts such as hydroxides and carbonates of monovalent and divalent metals such as sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate, and calcium carbonate; ammonia It can be carried out using alkaline substances such as organic amines.

  Further, in the method for producing a copolymer according to the present invention, as a promoter, reducing agents such as sodium bisulfite, sodium sulfite, Mole salt, sodium pyrobisulfite, sodium formaldehyde sulfoxylate, ascorbic acid; ethylenediamine, ethylenediaminetetraacetic acid You may use together amine compounds, such as sodium and glycine. The above accelerators may be used alone or in the form of a mixture of two or more.

  In the copolymerization method according to the present invention, the copolymerization conditions such as the copolymerization temperature are appropriately determined depending on the copolymerization method used, the solvent used, the type of the polymerization initiator and the chain transfer agent, etc. In order to obtain high monomer reactivity, the polymerization reaction is carried out at a temperature at which the half-life of the radical polymerization initiator is 0.5 to 500 hours, preferably 1 to 300 hours, more preferably 3 to 150 hours. For this reason, the copolymerization temperature is preferably preferably 0 ° C. or higher, and more preferably 150 ° C. or lower. More preferably, it is 40 degreeC or more, More preferably, it is 50 degreeC or more, Most preferably, it is 55 degreeC or more. More preferably, it is 120 degrees C or less, More preferably, it is 100 degrees C or less, Most preferably, it is 85 degrees C or less. For example, when persulfate is used as the initiator, the polymerization reaction temperature is suitably in the range of 40 to 90 ° C, preferably in the range of 42 to 85 ° C, and more preferably in the range of 45 to 80 ° C. Moreover, when hydrogen peroxide and L-ascorbic acid (salt) are used as an initiator, the polymerization reaction temperature is suitably in the range of 30 to 90 ° C, preferably in the range of 35 to 85 ° C, and 40 to 40%. A range of 80 ° C. is more preferable. The polymerization time is suitably in the range of 0.5 to 10 hours, preferably 0.5 to 8 hours, more preferably 1 to 6 hours. If the polymerization time is too long or too short from this range, the polymerization rate and productivity are lowered, which is not preferable.

  In the present invention, the mixing ratio of the monomers (A), (B) and (C) used in the polymerization of the copolymer is not particularly limited as long as the copolymer having a desired characteristic is obtained. The monomer (A) is preferably 40% by mass or more, more preferably 50 to 97% by mass, further preferably 60%, based on the total amount of the monomers (A), (B) and (C). To 95% by mass, and the monomer (B) is preferably 40% by mass or less, more preferably 1.0 to 38% by mass, still more preferably 2.0 to 35% by mass, and particularly preferably 3.0%. To 30% by mass, and the monomer (C) is preferably 30% by mass or less, more preferably 2.0 to 25% by mass, still more preferably 3.0 to 20% by mass, and particularly preferably 4.0. ˜15 mass%. Under the present circumstances, the sum total of a monomer (A), a monomer (B), and a monomer (C) is 100 mass%.

  In the method of the present invention, when the monomer (X) is further used, the mixing ratio of the monomer (X) is as follows: the monomer (A), the monomer (B) and the monomer ( The amount is 0.1 to 50% by mass, more preferably 0.5 to 20% by mass, and most preferably 1 to 10% by mass with respect to the total amount of C). Under the present circumstances, the sum total of a monomer (A), a monomer (B), and a monomer (C) is 100 mass%.

  The amount of the polymerization initiator (D) used is preferably 0.01 to 30 mol%, more preferably 0.1 to 20 mol%, most preferably 0 with respect to the total amount of the monomer components. It is good to set it as 5-10 mol%. If it is less than 0.01 mol%, the amount of unreacted monomers increases. On the other hand, if it exceeds 30 mol%, a polycarboxylic acid having a large amount of oligomers is obtained, which is not preferable.

  The amount of the reducing agent (E) used is preferably 0.1 to 500 mol%, more preferably 1 to 200 mol%, and most preferably 10 to 100 mol% with respect to the polymerization initiator (D). It is good to do. When the amount is less than 0.1 mol%, active radicals are not sufficiently generated and the amount of unreacted monomers increases. On the other hand, when the amount exceeds 500 mol%, the remaining reducing agent does not react with hydrogen peroxide. Therefore, it is not preferable.

  The amount of the chain transfer agent (F) used is preferably 0.5 to 6.0 mol%, more preferably based on the total amount of the monomers (A), (B) and (C). It is good to set it as 0.7-5.5 mol%, Most preferably, it is 1.0-5.0 mol%. When the amount is less than 0.5 mol%, active radicals are not sufficiently generated and the amount of unreacted monomers increases. On the other hand, when the amount exceeds 6.0 mol%, the remaining reducing agent does not react with hydrogen peroxide. Is unfavorable because of the increase in the number.

  Further, the copolymer for cement admixture according to the present invention is manufactured as a blend, and its weight average molecular weight is not particularly limited as long as it can exhibit desired characteristics. The weight average molecular weight is in the range of 5,000 to 300,000, more preferably 5,000 to 100,000, even more preferably 7 in terms of polyethylene glycol by gel permeation chromatography (hereinafter referred to as “GPC”). In the range of 8,000 to 80,000, most preferably 9,000 to 50,000. By selecting the mass ratio of these monomers and the range of the weight average molecular weight, a copolymer for cement admixture that exhibits higher dispersion performance can be produced. In this specification, a weight average molecular weight is measured by the method as described in the Example mentioned later.

  The cement admixture according to the present invention contains the above copolymer / copolymer blend as an essential component. The cement admixture according to the present invention may be composed solely of the copolymer blend according to the present invention or may contain other additives. Other additives that can be used in the latter case include those described in the following (1) to (20). Such a cement admixture can be mixed with cement and used as a cement composition. The cement admixture or copolymer according to the present invention is also effective for a hydraulic composition using a hydraulic material other than cement. Specifically, the copolymer according to the present invention and gypsum are essential. And a hydraulic composition. Moreover, the cement composition according to the present invention may further contain water, and by containing water, hydraulic properties are developed and hardened. The cement composition of the present invention may contain fine aggregate (sand, etc.), coarse aggregate (crushed stone, etc.) and the like as necessary. Specific examples of such a cement composition include cement paste, mortar, concrete, plaster and the like. The cement composition according to the present invention can also be used for ultra high strength concrete.

Ultra-high-strength concrete is generally called as such in the field of cement composition, that is, the cured product is equivalent to the conventional one even if the water / cement ratio is smaller than that of conventional concrete. Or concrete having higher strength, for example, the water / cement ratio is 25% by mass or less, further 20% by mass or less, particularly 18% by mass or less, particularly 14% by mass or less, especially about 12% by mass. However, it is a concrete having workability that does not hinder normal use, and its cured product is 60 N / mm ² or more, further 80 N / mm ² or more, even more 100 N / mm ² or more, particularly 120 N / mm ^2. or more, particularly 160 N / mm ² or more, especially those which show 200 N / mm ² or more compression strength.

  Such a cement composition will be described below.

  The cement that can be used is not particularly limited, and known cements can be used. For example, Portland cement (ordinary, early strength, ultra-early strength, moderate heat, sulfate-resistant and low alkali types thereof), various mixed cements ( Blast furnace cement, silica cement, fly ash cement), white Portland cement, alumina cement, super fast cement (1 clinker fast cement, 2 clinker fast cement, magnesium phosphate cement), grout cement, oil well cement, low heat cement (Low heat generation type blast furnace cement, fly ash mixed low heat generation type blast furnace cement, high belite content cement), ultra high strength cement, cement-based solidified material, eco-cement (city waste incineration ash, sewage sludge incineration ash as raw materials And the like) A blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder, a fine powder and gypsum limestone powder may be added.

In addition to gravel, crushed stone, granulated slag, recycled aggregate, etc., the aggregate includes siliceous, clay, zircon, high alumina, silicon carbide, graphite, chrome, chromic, magnesia. Refractory aggregate such as quality can be used. Further, in the cement composition, the unit water amount per 1 m ³ , the cement use amount and the water / cement ratio are not particularly limited, but the unit water amount is 100 to 185 kg / m ³ , the cement amount used is 250 to 800 kg / m ³ , water / Cement ratio = 10 to 70% by mass, preferably unit water amount 120 to 175 kg / m ³ , used cement amount 270 to 800 kg / m ³ , water / cement ratio = 20 to 65% is recommended. It can be used widely and is effective for both high-strength concrete with a large amount of unit cement and poor-mixed concrete with a unit cement amount of 300 kg / m ³ or less.

  In the cement composition, the blending ratio of the cement admixture is not particularly limited, but when used for mortar, concrete, etc. using hydraulic cement, the cement admixture is used with respect to 100 parts by mass of cement. Preferably, it is added in an amount of 0.01 to 10% by mass, preferably 0.05 to 8% by mass, more preferably 0.1 to 5% by mass. By this addition, various preferable effects such as reduction in unit water amount, increase in strength, and improvement in durability are brought about. If the blending ratio is less than 0.01%, the performance is insufficient. Conversely, even if a large amount exceeding 10% is used, the effect is practically peaked and disadvantageous in terms of economy. In addition, the said mass% is a value of solid content conversion.

  The cement admixture of the present invention can be used in combination with a commonly used cement dispersant. As the cement dispersant, the following are suitable.

  Lignin sulfonate; polyol derivative; naphthalene sulfonic acid formalin condensate; melamine sulfonic acid formalin condensate; polystyrene sulfonate; aminoaryl sulfonic acid-phenol-formaldehyde condensate as described in JP-A-1-113419, etc. Aminosulfonic acid type; as described in JP-A-7-267705, as a component (a), a copolymer of a polyalkylene glycol mono (meth) acrylic acid ester compound and a (meth) acrylic acid compound and / or A salt thereof, and as a component (b), a copolymer of a polyalkylene glycol mono (meth) allyl ether compound and maleic anhydride and / or a hydrolyzate thereof, and / or a salt thereof, and a component (c) As polyalkylene glycol mono (meth) a A cement dispersant containing a copolymer of a ruether compound and a maleic ester of a polyalkylene glycol compound and / or a salt thereof; as a component A as described in Japanese Patent No. 2508113, (meth) acrylic acid A copolymer of a polyalkylene glycol ester of (meth) acrylic acid (salt), a specific polyethylene glycol polypropylene glycol compound as the B component, and a concrete admixture comprising a specific surfactant as the C component; (Meth) acrylic acid polyethylene (propylene) glycol ester or polyethylene (propylene) glycol mono (meth) allyl ether, (meth) allyl sulfonic acid (salt), and (meth) as described in JP-A-62-216950 Co-weight consisting of acrylic acid (salt) Body.

  A copolymer comprising polyethylene (propylene) glycol ester of (meth) acrylic acid, (meth) allylsulfonic acid (salt), and (meth) acrylic acid (salt) as described in JP-A-1-226757; As described in JP-B-5-36377, polyethylene (propylene) glycol ester of (meth) acrylic acid, (meth) allylsulfonic acid (salt) or p- (meth) allyloxybenzenesulfonic acid (salt), and Copolymer comprising (meth) acrylic acid (salt); copolymer of polyethylene glycol mono (meth) allyl ether and maleic acid (salt) as described in JP-A-4-149056; JP-A-5-170501 Polyethylene glycol ester of (meth) acrylic acid, (meth) allylsulfonic acid Salt), (meth) acrylic acid (salt), alkanediol mono (meth) acrylate, polyalkylene glycol mono (meth) acrylate, and an α, β-unsaturated monomer having an amide group in the molecule. Polymer: polyethylene glycol mono (meth) allyl ether, polyethylene glycol mono (meth) acrylate, (meth) acrylic acid alkyl ester, (meth) acrylic acid (salt), as described in JP-A-6-191918, and Copolymer comprising (meth) allylsulfonic acid (salt) or p- (meth) allyloxybenzenesulfonic acid (salt); alkoxypolyalkylene glycol monoallyl ether and maleic anhydride as described in JP-A-5-43288 Copolymer with acid, hydrolyzate or salt thereof As described in JP-B-58-38380, a copolymer comprising polyethylene glycol monoallyl ether, maleic acid, and a monomer copolymerizable with these monomers, or a salt or ester thereof .

  As described in JP-B-59-18338, polyalkylene glycol mono (meth) acrylic acid ester monomer, (meth) acrylic acid monomer, and a monomer copolymerizable with these monomers A copolymer comprising a polymer; a copolymer comprising a (meth) acrylic acid ester having a sulfonic acid group and a monomer copolymerizable therewith as described in JP-A-62-1119147, or Salt thereof; as described in JP-A-6-271347, an esterification reaction product of a copolymer of an alkoxy polyalkylene glycol monoallyl ether and maleic anhydride and a polyoxyalkylene derivative having an alkenyl group at the terminal; As described in Kaihei 6-298555, an alkoxypolyalkylene glycol monoallyl ether and maleic anhydride Esterification reaction product of a polymer and a polyoxyalkylene derivative having a hydroxyl group at the terminal; as described in JP-A-62-68806, a specific unsaturated alcohol such as 3-methyl-3-buten-1-ol is mixed with ethylene oxide. Etc. added alkenyl ether monomers, unsaturated carboxylic acid monomers, copolymers consisting of monomers copolymerizable with these monomers, or polycarboxylic acids such as salts thereof (salt). These cement dispersants may be used alone or in combination of two or more.

  When the cement dispersant is used in combination, it is not uniquely determined depending on the type of cement dispersant to be used, blending, test conditions, etc., but the proportion of the blended mass of the cement admixture and the cement dispersant Is preferably 5 to 95:95 to 5. More preferably, it is 10-90: 90-10.

  Or the cement admixture of this invention can also be used in combination with another cement admixture (material). Examples of the other cement admixture include other known cement admixtures (materials) as shown below.

  (1) Water-soluble polymer substances: polyacrylic acid (sodium), polymethacrylic acid (sodium), polymaleic acid (sodium), unsaturated carboxylic acid polymer such as sodium salt of acrylic acid / maleic acid copolymer; polyethylene Polyoxyethylene or polyoxypropylene polymers such as glycol and polypropylene glycol or copolymers thereof; Nonionic cellulose ethers such as methylcellulose, ethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, carboxyethylcellulose, hydroxypropylcellulose; yeast glucan Or xanthan gum, β-1,3 glucan (both linear and branched), for example, curdlan, paramylon, bakiman Polysaccharides produced by microbial fermentation, such as scleroglucan, laminaran, etc .; polyacrylamide; polyvinyl alcohol; starch; starch phosphate ester; sodium alginate; gelatin; Grade compounds and the like.

  (2) Polymer emulsion: Copolymers of various vinyl monomers such as alkyl (meth) acrylate.

  (3) retarder: gluconic acid, glucoheptonic acid, arabonic acid, malic acid or citric acid, and oxycarboxylic such as inorganic salts or organic salts such as sodium, potassium, calcium, magnesium, ammonium, triethanolamine, etc. Acids and salts thereof; monosaccharides such as glucose, fructose, galactose, saccharose, xylose, apiose, ribose, isomerized sugar, oligosaccharides such as disaccharides and trisaccharides, oligosaccharides such as dextrins, and many dextran Sugars, sugars such as molasses containing them; sugar alcohols such as sorbitol; magnesium silicate; phosphoric acid and its salts or boric acid esters; aminocarboxylic acids and their salts; alkali-soluble proteins; humic acids; Phenol; polyhydric alcohol such as glycerin; Phosphonic acids such as minotri (methylenephosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephosphonic acid) and alkali metal salts and alkaline earth metal salts thereof And derivatives thereof.

  (4) Early strengthening agents / accelerators: soluble calcium salts such as calcium chloride, calcium nitrite, calcium nitrate, calcium bromide and calcium iodide; chlorides such as iron chloride and magnesium chloride; sulfates; potassium hydroxide; Sodium hydroxide; carbonate; thiosulfate; formate such as formic acid and calcium formate; alkanolamine; alumina cement; calcium aluminate silicate and the like.

  (5) Mineral oil-based antifoaming agent: cocoon oil, liquid paraffin, etc.

  (6) Fat and oil-based antifoaming agents: animal and vegetable oils, sesame oil, castor oil, alkylene oxide adducts thereof and the like.

  (7) Fatty acid-based antifoaming agent: oleic acid, stearic acid, and these alkylene oxide adducts.

  (8) Fatty acid ester antifoaming agent: glycerin monoricinoleate, alkenyl succinic acid derivative, sorbitol monolaurate, sorbitol trioleate, natural wax and the like.

  (9) Oxyalkylene antifoaming agents: polyoxyalkylenes such as (poly) oxyethylene (poly) oxypropylene adducts; diethylene glycol heptyl ether, polyoxyethylene oleyl ether, polyoxypropylene butyl ether, polyoxyethylene polyoxypropylene (Poly) oxyalkyl ethers such as 2-ethylhexyl ether and oxyethyleneoxypropylene adducts to higher alcohols having 12 to 14 carbon atoms; (poly) oxyalkylenes such as polyoxypropylene phenyl ether and polyoxyethylene nonylphenyl ether (Alkyl) aryl ethers; 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 2,5-dimethyl-3-hexyne-2,5-diol, 3-methyl-1- Spotted Acetylene ethers obtained by addition polymerization of alkylene oxide to acetylene alcohol such as -3-ol; (poly) oxyalkylene fatty acid esters such as diethylene glycol oleate, diethylene glycol laurate, ethylene glycol distearate; polyoxyethylene sorbitan (Poly) oxyalkylene sorbitan fatty acid esters such as monolaurate and polyoxyethylene sorbitan trioleate; (poly) oxyalkylene alkyl (aryl) such as sodium polyoxypropylene methyl ether sulfate and sodium polyoxyethylene dodecylphenol ether sulfate ) Ether sulfate esters; (Poly) oxy such as (poly) oxyethylene stearyl phosphate Ruki alkylene alkyl phosphate esters; polyoxyethylene such as polyoxyethylene lauryl amine (poly) oxyalkylene alkyl amines; polyoxyalkylene amide.

  (10) Alcohol-based antifoaming agent: octyl alcohol, hexadecyl alcohol, acetylene alcohol, glycols and the like.

  (11) Amide antifoaming agent: acrylate polyamine and the like.

  (12) Phosphate ester antifoaming agent: tributyl phosphate, sodium octyl phosphate, etc.

  (13) Metal soap type antifoaming agent: aluminum stearate, calcium oleate, etc.

  (14) Silicone antifoaming agent: dimethyl silicone oil, silicone paste, silicone emulsion, organically modified polysiloxane (polyorganosiloxane such as dimethylpolysiloxane), fluorosilicone oil and the like.

  (15) AE agent: resin soap, saturated or unsaturated fatty acid, sodium hydroxystearate, lauryl sulfate, ABS (alkyl benzene sulfonic acid), LAS (linear alkyl benzene sulfonic acid), alkane sulfonate, polyoxyethylene alkyl (phenyl) ether Polyoxyethylene alkyl (phenyl) ether sulfate or a salt thereof, polyoxyethylene alkyl (phenyl) ether phosphate or a salt thereof, protein material, alkenyl sulfosuccinic acid, α-olefin sulfonate, and the like.

  (16) Other surfactants: aliphatic monohydric alcohols having 6 to 30 carbon atoms in the molecule such as octadecyl alcohol and stearyl alcohol, and those having 6 to 30 carbon atoms in the molecule such as abiethyl alcohol Intramolecular such as alicyclic monohydric alcohol, dodecyl mercaptan, etc. Intramolecular such as monovalent mercaptan having 6-30 carbon atoms in the molecule, such as nonylphenol, alkylphenol having 6-30 carbon atoms in the molecule, dodecylamine, etc. 10 mol or more of an alkylene oxide such as ethylene oxide or propylene oxide was added to a carboxylic acid having 6 to 30 carbon atoms in the molecule such as an amine having 6 to 30 carbon atoms, lauric acid or stearic acid. Polyalkylene oxide derivatives; alkyl group or alkoxyl group as a substituent Alkyl diphenyl ether sulfonates in which two phenyl groups having a sulfone group are ether-bonded; various anionic surfactants; various cationic surfactants such as alkylamine acetate and alkyltrimethylammonium chloride; Nonionic surfactants; various amphoteric surfactants.

  (17) Waterproofing agent: fatty acid (salt), fatty acid ester, oil and fat, silicon, paraffin, asphalt, wax and the like.

  (18) Rust preventive: nitrite, phosphate, zinc oxide and the like.

  (19) Crack reducing agent: polyoxyalkyl ethers; alkanediols such as 2-methyl-2,4-pentanediol.

  (20) Expansion material: Ettlingite, coal, etc.

  Other known cement admixtures (materials) include cement wetting agents, thickeners, separation reducing agents, flocculants, drying shrinkage reducing agents, strength enhancers, self-leveling agents, rust preventives, colorants, and antifungal agents. Agents, blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder, gypsum and the like. These known cement admixtures (materials) may be used alone or in combination of two or more.

  The cement admixture of the present invention may be used in combination with the above-described known cement dispersant and cement admixture (material), in addition to those that improve the dispersibility of the cement composition, foam suppression, and the like.

  As a method of adding the cement admixture or the cement dispersant to the cement composition, it is preferable to mix these cement admixture or cement dispersant into a cement admixture so as to facilitate mixing into the cement composition. .

  In the above-mentioned cement composition, the following (A) to (F) are mentioned as particularly preferred embodiments for components other than cement and water.

  (A) A combination comprising two components of the cement admixture according to the present invention and an oxyalkylene-based antifoaming agent. The oxyalkylene antifoaming agent is not particularly limited, and known oxyalkylene antifoaming agents can be used. For example, polyoxyalkylenes, polyoxyalkylene alkyl ethers, polyoxyalkylene acetylene ethers, polyoxyalkylenes Alkylamines and the like can be used, and polyoxyalkylene alkylamines are particularly preferred. In addition, as a compounding mass ratio of an oxyalkylene type antifoamer, 0.01-20 mass% is preferable with respect to a cement admixture.

  (A) A combination comprising the three components of the cement admixture according to the present invention, an oxyalkylene antifoaming agent, and an AE agent. In this case, the same oxyalkylene antifoaming agent as in the above (a) can be used, and the AE agent is not particularly limited, and a known AE agent can be used. AE agent prepared can be used. Among these, resin alcohol, fatty acid soap, higher alcohol sulfate such as lauryl sulfate or a salt thereof, polyoxyethylene alkyl (phenyl) ether, polyoxyethylene alkyl (phenyl) ether sulfate or a salt thereof, polyoxyethylene alkyl ( Phenyl) ether phosphate or a salt thereof can be used. In addition, as a compounding mass ratio of a cement admixture and an antifoamer, 0.01-20 mass% is preferable with respect to a cement admixture. On the other hand, the blending mass ratio of the AE agent is preferably 0.001 to 2 mass% with respect to the cement.

  (C) A combination comprising the two components of the cement admixture according to the present invention and the material separation reducing agent. The material separation reducing agent is not particularly limited, and known material separation reducing agents can be used. For example, various thickening agents such as nonionic cellulose ethers, and a hydrocarbon structure having 4 to 30 carbon atoms as a partial structure. A compound having a hydrophobic substituent and a polyoxyalkylene chain obtained by adding 2 to 300 average addition moles of an alkylene oxide having 2 to 18 carbon atoms can be used. The blending mass ratio between the cement admixture and the material separation reducing agent is preferably 10/90 to 99.99 / 0.01, and more preferably 50/50 to 99.9 / 0.1. The cement composition of this combination is suitable as a high fluidity concrete, a self-filling concrete, and a self-leveling material.

  (D) A combination comprising two components of the cement admixture according to the present invention and a retarder. The retarder is not particularly limited and known retarders can be used. For example, oxycarboxylic acids such as gluconic acid (salt) and citric acid (salt), sugars such as glucose, sugar alcohols such as sorbitol, aminotril Phosphonic acids such as (methylenephosphonic acid) can be used, but oxycarboxylic acids are particularly preferred. The blending mass ratio between the cement admixture and the retarder is preferably in the range of 10/90 to 99.9 / 0.1, more preferably in the range of 20/80 to 99/1.

  (E) A combination comprising two components of the cement admixture according to the present invention and an accelerator. The accelerator is not particularly limited and known accelerators can be used. For example, soluble calcium salts such as calcium chloride, calcium nitrite and calcium nitrate, chlorides such as iron chloride and magnesium chloride, thiosulfate, Formates such as formic acid and calcium formate can be used. In addition, as a compounding mass ratio of a cement admixture and an accelerator, the range of 0.1 / 99.9 to 90/10 is preferable, and the range of 1/99 to 70/30 is more preferable.

  (F) A combination comprising two components of the cement admixture according to the present invention and a sulfonic acid-based dispersant having a sulfonic acid group in the molecule. The sulfonic acid-based dispersant is not particularly limited, and known sulfonic acid-based dispersants can be used. For example, lignin sulfonate, naphthalene sulfonic acid formalin condensate, melamine sulfonic acid formalin condensate, polystyrene sulfonic acid Aminosulfonic acid-based dispersants such as salts and aminoarylsulfonic acid-phenol-formaldehyde condensates can be used. Further, the blending mass ratio of the cement admixture and the sulfonic acid-based dispersant is preferably in the range of 5/95 to 95/5, and more preferably in the range of 10/90 to 90/10.

  As described above, the cement admixture according to the present invention can be suitably applied to various cement compositions and the like, and the fluidity is maintained with excellent slump retention properties of the cement composition and the like. Thus, it is possible to make the viscosity easy to work at the site where it is handled. Therefore, by using the cement admixture according to the present invention, the water reduction performance of the cement composition is improved, the strength and durability of the cured product are excellent, and it is easy to work at the site where the cement composition is handled. Since it becomes such viscosity, the work efficiency etc. in construction of civil engineering / building structures will be improved. Therefore, a cement composition containing the cement admixture according to the present invention is also included in the present invention.

  The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by mass” and “%” means “% by mass”.

  In the present specification, the weight average molecular weight of the copolymer is a value measured under the following GPC measurement conditions.

<Measurement conditions of molecular weight by GPC>
Column used: Tosoh Corporation, TSK guard column SWXL + TSKge1 G4000SWXL + G3000SWXL + G2000SWXL
Eluent: An eluent solution prepared by dissolving 115.6 g of sodium acetate trihydrate in a mixed solvent of 10999 g of water and 6001 g of acetonitrile and adjusting the pH to 6.0 with acetic acid is used.

Implanted amount: 100 μL of 0.5% eluent solution
Eluent flow rate: 0.8 mL / min
Column temperature: 40 ° C
Standard material: polyethylene glycol, peak top molecular weight (Mp) 272500, 219300, 85000, 46000, 24000, 12600, 4250, 7100, 1470.

Calibration curve order: cubic equation Detector: 410 manufactured by Japan Waters Inc. Differential refraction detector Analysis software: manufactured by Japan Waters Inc. MILLENNIUM Ver. 3.21.

  In the present specification, the “mortar test method” is performed as follows.

<Mortar test method>
A kneader for mechanical kneading, a spoon, a flow table, a flow cone, and a stick according to JIS-R5201-1997 were used. At this time, unless otherwise specified, a mortar test was performed in accordance with JIS-R5201-1997.

  The material and mortar used in the test consisted of 550 g ordinary portland cement manufactured by Taiheiyo Cement Co., 1350 g standard sand for cement strength test in accordance with JIS-R5201-1997, an aqueous copolymer solution and an antifoaming agent for cement admixture. 220 g of ion exchange water containing The solid content [nonvolatile component] in the aqueous copolymer solution is measured by removing a volatile component by heating and drying an appropriate amount of the aqueous copolymer solution at 130 ° C., and a predetermined amount of solid content [ The aqueous copolymer solution was weighed and used so that the non-volatile component was included. The antifoaming agent was added for the purpose of avoiding the influence of air bubbles on the dispersibility of the mortar composition so that the air amount was 3.0% or less. Specifically, the oxyalkylene-based antifoaming agent was used in an amount so as to be 0.1% with respect to the cement admixture copolymer. When the amount of air in the mortar is larger than 3.0%, the amount of the antifoaming agent is adjusted so that the amount of air becomes 3.0% or less.

  The mortar was prepared at room temperature (20 ± 2 ° C.) using a Hobart mortar mixer (model number N-50, manufactured by Hobart) for 4 minutes and 30 seconds. Specifically, a prescribed amount of cement is put in a kneading bowl, attached to a kneader and started at a low speed. 15 seconds after starting the paddle, a predetermined amount of water containing a copolymer for cement admixture and an antifoaming agent is added for 15 seconds. Then, sand is added and mixed at a low speed for 30 seconds, then at a high speed and continuously mixed for 30 seconds. Remove the kneader from the kneader and stop kneading for 120 seconds, then attach the kneader again to the kneader and knead for 60 seconds at high speed (4 minutes 30 minutes after starting at the first low speed) After 10 seconds, stir 10 times each with a spoon. The kneaded mortar is divided into two layers and packed in a flow cone placed on a flow table. Each layer is struck 15 times over the entire surface so that the tip of the stab stick is about half the depth of the layer, and finally, the shortage is compensated, the surface is smoothed, and the start is started at a low speed first. 6 minutes later, after the flow cone was lifted vertically, the diameter of the mortar spread on the table was measured in two directions, and this average value was taken as the flow value.

  Moreover, in this specification, the copolymer for cement admixtures obtained by the comparative example 1 or the comparative example 3 mentioned later is used as a reference substance of the flow value by the said mortar test method. Conventionally, the copolymer for cement admixture obtained in Comparative Examples 1 and 3 has been one of the copolymers for cement admixture exhibiting excellent water reduction performance.

Comparative Example 1
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen introducer and a reflux cooling device, 42.63 parts of ion-exchanged water, ethylene oxide on the hydroxyl group of 3-methyl-3-buten-1-ol (isoprenol) (Hereinafter referred to as IPN-50) (80% aqueous solution) (A) 297.10 parts were charged, and the reaction apparatus was purged with nitrogen under stirring, and a nitrogen atmosphere was added. After raising the temperature to 58 ° C., 12.18 parts of a 2% aqueous hydrogen peroxide solution (D) were added thereto, and 19.81 parts of a 50% aqueous acrylic acid solution (B) were added to a 50% aqueous solution of hydroxyethyl acrylate ( C) 26.40 parts were added dropwise over 3 hours. 2. An aqueous solution comprising 0.72 part of 3-mercaptopropionic acid (F), 0.32 part of L-ascorbic acid (E) and 50.86 parts of ion-exchanged water at the same time as the dropping of the monomer (B) is started. It was dripped over 5 hours. Thereafter, the temperature was maintained at 58 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 5. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature lower than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution (an aqueous solution containing a cement admixture copolymer) having a weight average molecular weight of 30,000. ) When the reaction rate was calculated | required by LC, the reaction rate of IPN-50 was 90%, and the reaction rate of acrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 1. The initial flow value was 180 mm, and the flow value after 60 minutes was 181 mm. In addition, the said copolymer aqueous solution was used as a standard substance of the mortar test of the comparative example 2 and Examples 1-3.

Example 1
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen introducer and a reflux cooling device was charged with 42.63 parts of ion-exchanged water and 297.10 parts of IPN-50 monomer (80% aqueous solution) (A). The reaction apparatus was purged with nitrogen under stirring, and the temperature was raised to 58 ° C. in a nitrogen atmosphere. Then, 12.18 parts of a 2% aqueous hydrogen peroxide solution (D) was added thereto, and an aqueous 50% acrylic acid solution (B1). An aqueous solution (F1) 7.05 composed of 6.60 parts for 1.5 hours, 0.72 parts of 3-mercaptopropionic acid and 25.43 parts of ion-exchanged water was added dropwise over 1.0 hour, and (B1) completion of the addition Subsequently, 13.21 parts of a 50% aqueous solution of acrylic acid (B2) is added for 1.5 hours, (F1) and the aqueous solution (F2) comprising 0.72 parts of 3-mercaptopropionic acid and 25.43 parts of ion-exchanged water following the completion of the dropping. 19.10 to 2 Over a period of 5 hours was dropped. At the same time as the dropping of the monomer (B1), 26.40 parts of a 50% aqueous solution of hydroxyethyl acrylate (C) was dropped over 3 hours, 0.32 parts of L-ascorbic acid (E), and 25.43 ion-exchanged water. The aqueous solution consisting of parts was added dropwise over 3.5 hours. Thereafter, the temperature was maintained at 58 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 5. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature not higher than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution (an aqueous solution containing a cement admixture copolymer) having a weight average molecular weight of 32,000. ) When the reaction rate was calculated | required by LC, the reaction rate of IPN-50 was 90%, and the reaction rate of acrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 1. The initial flow value was 160 mm, the flow value after 60 minutes was 192 mm, and the retention was improved by 20% compared to the copolymer for cement admixture obtained in Comparative Example 1.

Example 2
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen introducer and a reflux cooling device was charged with 42.63 parts of ion-exchanged water and 297.10 parts of IPN-50 monomer (80% aqueous solution) (A). The reaction apparatus was purged with nitrogen under stirring, and the temperature was raised to 58 ° C. in a nitrogen atmosphere. Then, 12.18 parts of a 2% aqueous hydrogen peroxide solution (D) was added thereto, and an aqueous 50% acrylic acid solution (B1). 6.60 parts and 12.67 parts of a 50% aqueous solution of hydroxyethyl acrylate (C1) were added dropwise over 1.5 hours. (B1) 13.21 parts of a 50% aqueous solution of acrylic acid (B2) (C1) following the completion of the dropping. ) Subsequent to the completion of dropping, 13.73 parts of a 50% aqueous solution of hydroxyethyl acrylate (C2) was added dropwise over 1.5 hours. 2. An aqueous solution composed of 0.72 part of 3-mercaptopropionic acid (F), 0.32 part of L-ascorbic acid (E) and 50.86 parts of ion-exchanged water at the same time as the dropping of the monomer (B1) was started. It was dripped over 5 hours. Thereafter, the temperature was maintained at 58 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 5. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature not higher than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution having a weight average molecular weight of 28000 (an aqueous solution containing a cement admixture copolymer). ) When the reaction rate was calculated | required by LC, the reaction rate of IPN-50 was 90%, and the reaction rate of acrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 1. The initial flow value was 161 mm, the flow value after 60 minutes was 184 mm, and the retention was improved by 14% compared to the copolymer for cement admixture obtained in Comparative Example 1.

Example 3
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen introducer and a reflux cooling device was charged with 42.63 parts of ion-exchanged water and 297.10 parts of IPN-50 monomer (80% aqueous solution) (A). The reaction apparatus was purged with nitrogen under stirring, and the temperature was raised to 58 ° C. in a nitrogen atmosphere. Then, 7.90 parts of a 2% aqueous hydrogen peroxide solution (D1) was added dropwise over 2.0 hours, and L-ascorbine was added. 1.03 parts of an aqueous solution (E1) consisting of 0.32 parts of acid and 25.43 parts of ion-exchanged water was added dropwise over 0.5 hours. (D1) Subsequent to completion of dropping, 4.28 parts of a 2% aqueous hydrogen peroxide solution (D2) is added for 1.0 hour, and (E1) following completion of dropping, from 0.32 parts of L-ascorbic acid and 25.43 parts of ion-exchanged water. An aqueous solution (E2) 24.72 parts was added dropwise over 3.0 hours. At the same time as the dropwise addition of 2% aqueous hydrogen peroxide (D1), 19.81 parts of 50% aqueous acrylic acid (B) and 26.40 parts of 50% aqueous hydroxyethyl acrylate (C) were added for 3 hours to 3-mercaptopropion. An aqueous solution composed of 0.72 parts of acid (F) and 25.43 parts of ion-exchanged water was added dropwise over 3.5 hours. Thereafter, the temperature was maintained at 58 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 5. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature lower than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution (an aqueous solution containing a cement admixture copolymer) having a weight average molecular weight of 30,000. ) When the reaction rate was calculated | required by LC, the reaction rate of IPN-50 was 90%, and the reaction rate of acrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 1. The initial flow value was 160 mm, the flow value after 60 minutes was 173 mm, and the retention was improved by 8% compared to the copolymer for cement admixture obtained in Comparative Example 1.

Comparative Example 2
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen introducer and a reflux cooling device was charged with 42.63 parts of ion-exchanged water and 297.10 parts of IPN-50 monomer (80% aqueous solution) (A). The reaction apparatus was purged with nitrogen under stirring, and the temperature was raised to 58 ° C. in a nitrogen atmosphere. Then, 12.18 parts of a 2% aqueous hydrogen peroxide solution (D) was added thereto, and an aqueous 50% acrylic acid solution (B1). 9.51 parts were added dropwise over 1.5 hours, and (B1) 10.30 parts of 50% aqueous solution of acrylic acid (B2) was added dropwise over 1.5 hours following the completion of the addition. At the same time as the dropping of the monomer (B1), 26.40 parts of a 50% aqueous solution of hydroxyethyl acrylate (C) was dropped over 3 hours, 0.72 parts of 3-mercaptopropionic acid (F), L-ascorbic acid ( E) An aqueous solution consisting of 0.32 parts and ion-exchanged water 50.86 parts was added dropwise over 3.5 hours. Thereafter, the temperature was maintained at 58 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 5. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature lower than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution (an aqueous solution containing a cement admixture copolymer) having a weight average molecular weight of 30,000. ) When the reaction rate was calculated | required by LC, the reaction rate of IPN-50 was 90%, and the reaction rate of acrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 1. The initial flow value was 175 mm, the flow value after 60 minutes was 179 mm, and the retention was improved by 2% compared to the copolymer for cement admixture obtained in Comparative Example 1.

Comparative Example 3
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen inlet and a reflux cooling device was charged with 38.34 parts of ion-exchanged water and 237.55 parts of IPN-50 monomer (80% aqueous solution) (A). The reaction apparatus was purged with nitrogen under stirring, the temperature was raised to 58 ° C. under a nitrogen atmosphere, 18.37 parts of a 2% aqueous hydrogen peroxide solution (D) was added thereto, and then an 82% aqueous hydroxyethyl acrylate solution (C1 ) 19.30 parts were added dropwise over 1.5 hours, and (C1) 9.65 parts of 82% aqueous solution of hydroxyethyl acrylate (C1) was added dropwise over 1.5 hours following completion of the addition. At the same time that the monomer (C1) was added dropwise, 23.41 parts of a 78% aqueous solution of acrylic acid (B) was added dropwise over 3 hours, and 1.09 parts of 3-mercaptopropionic acid (F), L-ascorbic acid ( E) An aqueous solution composed of 0.48 parts and 56.06 parts of ion-exchanged water was added dropwise over 3.5 hours. Thereafter, the temperature was maintained at 58 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 4. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature lower than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution (an aqueous solution containing a cement admixture copolymer) having a weight average molecular weight of 30,000. ) When the reaction rate was calculated | required by LC, the reaction rate of IPN-50 was 90%, and the reaction rate of acrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 0. The initial flow value was 173 mm.

Comparative Example 4
A glass reactor equipped with a thermometer, a stirrer, a dropping device, a nitrogen introducer and a reflux cooling device was charged with 67.50 ion-exchanged water, and the reactor was purged with nitrogen under stirring, and the temperature was raised to 80 ° C. under a nitrogen atmosphere. After the temperature was raised, 75.00 parts of a hydrogen peroxide 0.42% aqueous solution (D) was added dropwise over 5 hours, and 75.00 parts of an L-ascorbic acid 0.55% aqueous solution (E) was added dropwise over 5 hours. At the same time as the dropwise addition of 0.48% aqueous solution of hydrogen peroxide (D), ethylene oxide was added to the hydroxyl group of methanol (average added mole number of ethylene oxide 10), and methacrylic acid was esterified (hereinafter referred to as PGM-). 10E) (A) 137.94 parts, methacrylic acid (B) 42.26 parts, hydroxyethyl acrylate (C) 21.22 parts, ion-exchanged water 18.75 parts, 3-mercaptopropionic acid (F) 5 An aqueous solution consisting of 0.78 parts and 6.55 parts of a 30% aqueous sodium hydroxide solution was added dropwise over 4 hours. (D), (E) After completion of the dropwise addition, the temperature was maintained at 80 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 5. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature lower than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution (an aqueous solution containing a cement admixture copolymer) having a weight average molecular weight of 20000. ) When the reaction rate was determined by LC, the reaction rate of PGM-10E was 97%, and the reaction rate of methacrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 0. The initial flow value was 173 mm.

Example 4
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen inlet and a reflux cooling device was charged with 34.08 parts of ion-exchanged water and 237.55 parts of IPN-50 monomer (80% aqueous solution) (A). The reaction apparatus was purged with nitrogen under stirring, and the temperature was raised to 58 ° C. in a nitrogen atmosphere, followed by 15.60 parts of a 78% aqueous solution of acrylic acid (B1) and 12.25% aqueous solution of hydrogen peroxide (D1) 12.25. (B1) 7.80 parts of a 78% aqueous solution of acrylic acid (B2) following the end of dropping, (D1) 2% aqueous solution of hydrogen peroxide (D2) 6. 12 parts were added dropwise over 1.5 hours. At the same time when the monomer (B1) was added dropwise, 28.96 parts of a 82% aqueous solution of hydroxyethyl acrylate (C) was added dropwise over 3 hours, and 1.09 parts of 3-mercaptopropionic acid (F), L-ascorbic acid ( E) An aqueous solution composed of 0.48 parts and 56.06 parts of ion-exchanged water was added dropwise over 3.5 hours. Thereafter, the temperature was maintained at 58 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 4. Thereafter, the reaction solution is neutralized to pH 7 using a sodium hydroxide aqueous solution at a temperature not higher than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution having a weight average molecular weight of 30000 (an aqueous solution containing a cement admixture copolymer). ) When the reaction rate was calculated | required by LC, the reaction rate of IPN-50 was 90%, and the reaction rate of acrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 0. The initial flow value was 205 mm, and the fluidity was improved by 32 mm compared to the cement admixture copolymer obtained in Comparative Example 3.

Example 5
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen inlet and a reflux cooling device was charged with 34.08 parts of ion-exchanged water and 237.55 parts of IPN-50 monomer (80% aqueous solution) (A). The reaction apparatus was purged with nitrogen under stirring, and the temperature was raised to 58 ° C. under a nitrogen atmosphere. Then, 18.37 parts of a 2% aqueous hydrogen peroxide solution (D) was added thereto, and an aqueous 78% acrylic acid solution (B1) was added. 15.60 parts and 18.31 parts of 82% aqueous solution of hydroxyethyl acrylate (C1) were added dropwise over 1.5 hours. (B1) After completion of dropping, 7.80 parts of 78% aqueous solution of acrylic acid (B2), (C1 ) Subsequent to the completion of dropping, 9.65 parts of 82% aqueous solution (C2) of hydroxyethyl acrylate was added dropwise over 1.5 hours. 2. An aqueous solution comprising 1.09 parts of 3-mercaptopropionic acid (F), 0.48 parts of L-ascorbic acid (E) and 56.06 parts of ion-exchanged water at the same time as the dropping of the monomer (B1) is started. It was dripped over 5 hours. Thereafter, the temperature was maintained at 58 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 4. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature not higher than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution (an aqueous solution containing a cement admixture copolymer) having a weight average molecular weight of 32,000. ) When the reaction rate was calculated | required by LC, the reaction rate of IPN-50 was 90%, and the reaction rate of acrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 0. The initial flow value was 200 mm, and the initial fluidity was improved by 28 mm compared to the cement admixture copolymer obtained in Comparative Example 3.

Example 6
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen inlet and a reflux cooling device was charged with 34.08 parts of ion-exchanged water and 237.55 parts of IPN-50 monomer (80% aqueous solution) (A). The reaction apparatus was purged with nitrogen under stirring, and the temperature was raised to 58 ° C. in a nitrogen atmosphere. Then, 12.25 parts of a 2% aqueous hydrogen peroxide solution (D1) was added dropwise over 1.5 hours, and (D1) Following completion of the dropwise addition, 6.12 parts of a 2% aqueous hydrogen peroxide solution (D2) was added dropwise over 1.5 hours. At the same time as the dropwise addition of the 2% aqueous hydrogen peroxide solution (D1), 12.78 parts of an aqueous solution (E1) consisting of 0.48 parts of L-ascorbic acid and 28.03 parts of ion-exchanged water, 1. mercaptopropionic acid 1. An aqueous solution (F1) consisting of 09 parts and 28.03 parts of ion-exchanged water was added dropwise over 1.5 hours. (E1) and (F1) 0.48 parts of L-ascorbic acid following the completion of the addition. And 15.73 parts of an aqueous solution (E2) comprising 28.03 parts of ion-exchanged water, and 16.07 parts of an aqueous solution (F2) comprising 1.09 parts of 3-mercaptopropionic acid and 28.03 parts of ion-exchanged water, respectively. The solution was added dropwise over 0 hours. At the same time as the dropwise addition of 2% aqueous hydrogen peroxide (D1), 23.41 parts of 78% aqueous acrylic acid (B) and 28.96 parts of 82% aqueous hydroxyethyl acrylate (C) were added dropwise over 3 hours. . The pH at the end of the polymerization was 4. Thereafter, the temperature was maintained at 58 ° C. for 1 hour, followed by cooling to complete the polymerization. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature not higher than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution having a weight average molecular weight of 28000 (an aqueous solution containing a cement admixture copolymer). ) When the reaction rate was calculated | required by LC, the reaction rate of IPN-50 was 90%, and the reaction rate of acrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 0. The initial flow value was 179 mm, and the initial fluidity was improved by 6 mm compared with the cement admixture copolymer obtained in Comparative Example 3.

Example 7
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen inlet and a reflux cooling device was charged with 34.08 parts of ion-exchanged water and 237.55 parts of IPN-50 monomer (80% aqueous solution) (A). The reaction apparatus was purged with nitrogen under stirring, and the temperature was raised to 58 ° C. under a nitrogen atmosphere. Then, 18.37 parts of a 2% aqueous hydrogen peroxide solution (D) was added thereto, and an aqueous 78% acrylic acid solution (B1) was added. 15.60 parts and 18.31 parts of 82% aqueous solution of hydroxyethyl acrylate (C1) were added dropwise over 1.5 hours. (B1) After completion of dropping, 7.80 parts of 78% aqueous solution of acrylic acid (B2), (C1 ) Subsequent to the completion of dropping, 9.65 parts of 82% aqueous solution (C2) of hydroxyethyl acrylate was added dropwise over 1.5 hours. At the same time as the dropping of the monomer (B1), 4.36 parts of an aqueous solution (E1) comprising 0.48 part of L-ascorbic acid and 28.03 parts of ion-exchanged water was added for 0.5 hour to 3-mercaptopropionic acid 1 17.21 parts of an aqueous solution (F1) consisting of 0.09 parts and 28.03 parts of ion-exchanged water was added dropwise over 2.0 hours, and (E1) 0.48 parts of L-ascorbic acid and ion-exchanged water were continued after the completion of the addition. Aqueous solution (E2) consisting of 28.03 parts 24.15 parts for 3.0 hours, (F1) After completion of dropping, aqueous solution (F2) consisting of 1.09 parts 3-mercaptopropionic acid and 28.03 parts ion-exchanged water 11.91 parts was dripped over 1.5 hours. Thereafter, the temperature was maintained at 58 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 4. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature lower than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution (an aqueous solution containing a cement admixture copolymer) having a weight average molecular weight of 30,000. ) When the reaction rate was calculated | required by LC, the reaction rate of IPN-50 was 90%, and the reaction rate of acrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 0. The initial flow value was 200 mm, and the initial fluidity was improved by 27 mm compared with the cement admixture copolymer obtained in Comparative Example 3.

Example 8
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen inlet and a reflux cooling device was charged with 34.08 parts of ion-exchanged water and 237.55 parts of IPN-50 monomer (80% aqueous solution) (A). The reactor was purged with nitrogen under stirring, and the temperature was raised to 58 ° C. in a nitrogen atmosphere. Then, 4.68 parts of a 78% aqueous solution of acrylic acid (B1) was added to the aqueous solution of 2% hydrogen peroxide (1.0%) for 1.0 hour. D1) 12.25 parts were added dropwise over 1.5 hours, and (B1) after completion of dropping, 7.02 parts of 78% aqueous solution of acrylic acid (B2) was added for 1.0 hour, and (D1) peroxidation was continued after completion of dropping. 6.12 parts of hydrogen 2% aqueous solution (D2) was added dropwise over 1.5 hours, and (B2) 11.71 parts of 78% aqueous solution of acrylic acid (B3) was added dropwise over 1.0 hour. At the same time as the addition of monomer B1, 28.96 parts of 82% aqueous solution of hydroxyethyl acrylate (C) was added dropwise over 3 hours, 1.09 parts of 3-mercaptopropionic acid (F), L-ascorbic acid (E) An aqueous solution consisting of 0.48 parts and 56.06 parts of ion-exchanged water was added dropwise over 3.5 hours. Thereafter, the temperature was maintained at 58 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 4. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature lower than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution (an aqueous solution containing a cement admixture copolymer) having a weight average molecular weight of 30,000. ) When the reaction rate was calculated | required by LC, the reaction rate of IPN-50 was 90%, and the reaction rate of acrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 0. The initial flow value was 179 mm, and the initial fluidity was improved by 6 mm compared with the cement admixture copolymer obtained in Comparative Example 3.

Example 9
In a glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen introducer and a reflux cooling device, 34.34 parts of ion-exchanged water and a hydroxyl group of 2-methyl-2-propen-1-ol (methallyl alcohol) To which ethylene oxide was added (average added mole number of ethylene oxide 150) (hereinafter referred to as MLA-150) (80% aqueous solution) (A) 267.25 parts were charged, and the reactor was purged with nitrogen under stirring. After raising the temperature to 58 ° C. in a nitrogen atmosphere, 18.58 parts of a 2% aqueous hydrogen peroxide solution (D) was added thereto, and then 17.01 parts of a 78% aqueous acrylic acid solution (B1) was added over 1.5 hours. Dropping, 22.38 parts (F1) of an aqueous solution composed of 0.70 part of 3-mercaptopropionic acid and 32.87 parts of ion-exchanged water was added dropwise over 1.75 hours. (B1) After completion of dropping, 8.50 parts of 80% aqueous solution of acrylic acid (B2) was dropped over 1.5 hours. (F1) Following completion of dropping, 0.70 part of 3-mercaptopropionic acid and 32.87 ion-exchanged water. 11.19 parts of an aqueous solution consisting of parts (F2) was added dropwise over 1.75 hours. At the same time when the monomer B1 was added dropwise, 33.41 parts of an 80% aqueous solution of hydroxyethyl acrylate (C) was added dropwise over 3 hours, from 0.48 parts of L-ascorbic acid (E) and 32.87 parts of ion-exchanged water. The resulting aqueous solution was added dropwise over 3.5 hours. Thereafter, the temperature was maintained at 58 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 4. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature not higher than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution (an aqueous solution containing a cement admixture copolymer) having a weight average molecular weight of 50,000. ) When the reaction rate was determined by LC, the reaction rate of MLA-150 was 90%, and the reaction rate of acrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 0. The initial flow value was 178 mm, and the initial fluidity was improved by 5 mm compared with the cement admixture copolymer obtained in Comparative Example 3.

Example 10
A glass reactor equipped with a thermometer, a stirrer, a dropping device, a nitrogen introducer and a reflux cooling device was charged with 67.50 ion-exchanged water, and the reactor was purged with nitrogen under stirring, and the temperature was raised to 80 ° C. under a nitrogen atmosphere. After heating, 50.00 parts of hydrogen peroxide 0.42% aqueous solution (D1) was added to 2.5 hours, and 50.00 parts of L-ascorbic acid 0.55% aqueous solution (E1) was taken 2.5 hours. It was dripped. (D1) 25.00 parts of hydrogen peroxide 0.42% aqueous solution (D2) continued for 2.5 hours following the end of dropping, (E1) 0.55% aqueous solution of L-ascorbic acid (E2) 25.00 following the end of dropping The portion was added dropwise over 2.5 hours. At the same time as dropwise addition of 0.42% aqueous hydrogen peroxide (E1), ethylene oxide was added to the hydroxyl group of methanol (average added mole number of ethylene oxide 10), and methacrylic acid was esterified (hereinafter PGM- 10E) (A) 137.94 parts, methacrylic acid (B) 42.26 parts, hydroxyethyl acrylate (C) 21.22 parts, ion-exchanged water 18.75 parts, 3-mercaptopropionic acid (F) 5 An aqueous solution consisting of 0.78 parts and 6.55 parts of a 30% aqueous sodium hydroxide solution was added dropwise over 4 hours. (D2), (E2) After completion of dropping, the temperature was continuously maintained at 80 ° C. for 1 hour, followed by cooling to complete the polymerization. The pH at the end of the polymerization was 5. Thereafter, the reaction solution is neutralized to pH 6 using a sodium hydroxide aqueous solution at a temperature lower than the polymerization reaction temperature (30 ° C.), and a copolymer aqueous solution (an aqueous solution containing a cement admixture copolymer) having a weight average molecular weight of 20000. ) When the reaction rate was determined by LC, the reaction rate of PGM-10E was 97%, and the reaction rate of methacrylic acid and hydroxyethyl acrylate was 98%, respectively. As a result of using the obtained aqueous copolymer solution in the mortar test, the amount of solid content in the aqueous copolymer solution added to the mortar (the amount of solid content in the aqueous copolymer solution added to the mortar) was 0. The initial flow value was 178 mm, and the initial fluidity was improved by 5 mm compared with the cement admixture copolymer obtained in Comparative Example 4.

Claims (6)

Following formula (1):

Where
R ¹ , R ² and R ³ each independently represents a hydrogen atom or a methyl group,
R ^a O each independently represents one or more of oxyalkylene groups having 2 or more carbon atoms,
m represents a number of 1 to 300 in terms of the average number of moles added of the oxyalkylene group;
x represents an integer of 0 to 2;
y represents 0 or 1,
R ⁴ represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms,
At least one unsaturated polyalkylene glycol ether monomer (A) represented by:
Following formula (2):

Where
R ⁵ , R ⁶ and R ⁷ are each independently a hydrogen atom, a methyl group or — (CH ₂ ) _z COOM ² group (— (CH ₂ ) _z COOM ² is —COOM ¹ or other — (CH ₂ ) _z COOM ² and may form an anhydride), z represents an integer of 0-2;
M ¹ and M ² each independently represent a hydrogen atom, an alkali metal atom, an alkaline earth metal atom, an ammonium group or an organic ammonium group.
And at least one unsaturated organic acid monomer (B) represented by the following formula (3):

Where
R ⁸ , R ⁹ and R ¹⁰ each independently represent a hydrogen atom, a methyl group, or — (CH ₂ ) _n COOR ¹² group, and n represents an integer of 0 to 2;
R ¹¹ and R ¹² represent a C 1-20 alkyl group having a C 1-20 alkyl group, a C 1-20 hydroxyalkyl group, or a C 1-20 alkoxy group,
A method for producing a cement admixture having a polymerization step for polymerizing a monomer component containing at least one unsaturated carboxylic acid ester monomer (C) represented by:
In the polymerization step, two or more components are continuously added to the reaction system, and the addition rate of at least two of the continuously added components is changed at least once and added to the reaction system. The manufacturing method of the copolymer for agents.   The production according to claim 1, wherein the continuously added component includes at least one selected from the group consisting of a polymerization initiator (D), a reducing agent (E), and a chain transfer agent (F). Method.   The unsaturated organic acid monomer (B), the unsaturated carboxylic acid ester monomer (C), the polymerization initiator (D), the reducing agent (E), and the chain transfer agent (F) The production method according to claim 2, wherein the addition rate of at least two components selected from the group consisting of is changed to at least one time and added to the reaction system.   The y of said Formula (1) is 0, Comprising: The said unsaturated polyalkylene glycol ether monomer (A) is added to reaction container previously, The any one of Claims 1-3 Production method.   In the formula (1), y is 1, and the unsaturated polyalkylene glycol ether monomer (A) is an unsaturated organic acid monomer (B) and an unsaturated carboxylic acid ester monomer. The manufacturing method of any one of Claims 1-3 added simultaneously with a monomer (C).   A cement admixture comprising the polycarboxylic acid polymer for cement admixture obtained by the production method according to any one of claims 1 to 5.