TW201821521A - Acrylic rubber and method for producing same - Google Patents

Abstract

Provided is an acrylic rubber containing a lubricant, the lubricant being at least one selected from among phosphate ester, fatty acid ester, fatty acid amide, and higher fatty acid. According to the present invention, an acrylic rubber which has excellent handleability when dried, and has excellent roll processability can be provided.

Description

Acrylic rubber and its manufacturing method, acrylic rubber composition and rubber crosslinked product

The present invention relates to acrylic rubber and a method for producing the same, and more specifically, to an acrylic rubber having excellent handleability and roll processability during drying, and a method for producing such an acrylic rubber.

Acrylic rubber is a polymer containing acrylate as a main component, and is generally known as a rubber excellent in heat resistance, oil resistance, and ozone resistance, and is widely used in automotive-related fields.

Such an acrylic rubber is generally prepared by emulsifying and polymerizing a monomer mixture constituting the acrylic rubber, and adding a coagulant to the obtained emulsified polymerization solution to agglomerate the same, and performing the water-containing crumb obtained by agglomeration. It is manufactured by drying (for example, refer to Patent Document 1: Japanese Patent Laid-Open No. 7-145291). In the drying of the water-containing pellets, a hot-air dryer can be generally used. However, from the viewpoint of productivity, a drying device such as a belt dryer of a belt conveyor type capable of drying in a continuous step is used. On the other hand, in the drying of such an acrylic rubber, the acrylic rubber is softened by the temperature at the time of drying and causes adhesion to a wall surface of a drying device, etc., so there is a problem that operability is reduced. In addition, conventional acrylic rubbers such as the acrylic rubber described in Patent Document 1 are liable to cause sticking to the roller when the roller is used and various admixtures are blended, and there are also inadequate processability when the roller is used for processing. Topic.

The present invention has been made in view of such circumstances, and an object thereof is to provide an acrylic rubber having excellent handleability and roll processability during drying, and a method for producing the same. It is also an object of the present invention to provide an acrylic rubber composition and a rubber crosslinked product using such an acrylic rubber.

The present inventors conducted intensive studies in order to achieve the above-mentioned object, and as a result, they found that by including a specific slip agent in acrylic rubber, the above-mentioned object can be achieved, and the present invention has been completed.

That is, according to the present invention, it is possible to provide an acrylic rubber containing a lubricant selected from the group consisting of phosphate esters, fatty acid esters, stearylamine, and higher fatty acids.

The slip agent preferably contains at least one selected from the group consisting of a phosphate ester and a higher fatty acid, and more preferably contains a polyoxyethylene higher alcohol phosphoric acid or a fatty acid having 12 to 20 carbon atoms.

The content of the lubricant is preferably 0.1 to 0.4% by weight, and more preferably 0.2 to 0.3% by weight.

The acrylic rubber of the present invention preferably has an acrylic rubber content of 95% by weight or more.

The acrylic rubber is preferably an acrylic rubber containing a carboxyl group.

According to the present invention, there can be provided an acrylic rubber composition containing the above-mentioned acrylic rubber and a crosslinking agent, and a rubber crosslinked product obtained by crosslinking such an acrylic rubber composition.

In addition, according to the present invention, there is provided a method for manufacturing an acrylic rubber, which is a method for manufacturing the above-mentioned acrylic rubber, and includes the following steps: an emulsification polymerization step, wherein the monomers for forming the aforementioned acrylic rubber are subjected to emulsion polymerization to obtain An emulsification polymerization solution; a lubricant addition step, in which the lubricant is contained in the emulsion polymerization solution before coagulation; and a coagulation step, in which an agglomerating agent is added to the emulsion polymerization solution and coagulated to obtain water-containing pellets.

Alternatively, according to the present invention, there is provided a method for manufacturing an acrylic rubber, which is a method for manufacturing the above-mentioned acrylic rubber, and includes the following steps: an emulsion preparation step in which a monomer for forming the aforementioned acrylic rubber is combined with an emulsifier and water Mixing to obtain a monomer emulsion; the lubricant addition step is to add the lubricant to the monomer emulsion prepared in the aforementioned emulsion preparation step; the emulsion polymerization step is to add the lubricant to the aforementioned lubricant addition step The monomers contained in the formed monomer emulsion are subjected to emulsion polymerization to obtain an emulsion polymerization solution; and a coagulation step is performed by adding a coagulant to the aforementioned emulsion polymerization solution and aggregating them, thereby obtaining water-containing pellets.

In the manufacturing method of the present invention, the amount of the lubricant added in the lubricant adding step is preferably set to 0.1 to 0.4 parts by weight with respect to 100 parts by weight of the acrylic rubber component contained in the emulsion polymerization solution. It is preferably set to 0.2 to 0.3 parts by weight.

In the manufacturing method of this invention, it is preferable to perform emulsion polymerization of the said monomer in the said emulsion polymerization process in the presence of a nonionic emulsifier and an anionic emulsifier.

In the manufacturing method of this invention, it is preferable to set the usage-amount of the said nonionic emulsifier and anionic emulsifier to 50 / 50-75 / based on the weight ratio of a nonionic emulsifier / anionic emulsifier. 25.

In the production method of the present invention, preferably, in the aforementioned emulsion polymerization step, the monomer, the polymerization initiator and the reducing agent for forming the acrylic rubber are continuously dropped to polymerization from the start of the polymerization reaction to an arbitrary time. The reaction system also performs an emulsion polymerization reaction at the same time.

Further, in the production method of the present invention, it is preferable that the monomer emulsion used to form the acrylic rubber is a state of a monomer emulsion obtained by mixing the monomer with an emulsifier and water from the start of the polymerization reaction to an arbitrary time. , Continuously dripping to the polymerization reaction system and simultaneously carrying out the emulsion polymerization reaction.

According to the present invention, there are provided an acrylic rubber excellent in handleability and roll processability during drying, and a method for producing such an acrylic rubber.

＜ Acrylic rubber ＞

The acrylic rubber of the present invention contains (meth) acrylic acid ester monomers [acrylic acid ester monomers and / Or methacrylate monomer. The meaning of methyl (meth) acrylic acid (to be described later is the same meaning)] is a rubber-like polymer of a unit, and is a lubricant containing at least one selected from the group consisting of phosphate esters, fatty acid esters, stearylamine, and higher fatty acids.

The main component of the acrylic rubber of the present invention is a (meth) acrylate monomer unit. The (meth) acrylate monomer forming the (meth) acrylate monomer unit is not particularly limited, but examples thereof include For example, an (meth) acrylic acid alkyl ester monomer, (meth) actylic acid alkoxyalkyl ester monomer, and the like.

Although it does not specifically limit as an (meth) acrylic-acid alkylester monomer, It is preferable that it is an ester of alkanol of 1-8 carbon and (meth) acrylic acid. Specific examples include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, Isobutyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, and the like. Among these, ethyl (meth) acrylate and n-butyl (meth) acrylate are preferred. Ethyl acrylate and n-butyl acrylate are preferred. These can be used alone or in combination of two or more.

The alkoxyalkyl (meth) acrylate monomer is not particularly limited, but an alkoxy alkyl alcohol having 2 to 8 carbons and an ester of (meth) acrylic acid are preferred. Specific examples include: methoxymethyl (meth) acrylate, ethoxymethyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate , 2-propoxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, 3-methoxypropyl (meth) acrylate, 4-methoxybutyl (meth) acrylate, etc. . Among these, 2-ethoxyethyl (meth) acrylate and 2-methoxyethyl (meth) acrylate are preferred, and 2-ethoxyethyl acrylate and 2-methoxyethyl acrylate are preferred. Is better. These can be used alone or in combination of two or more.

In the acrylic rubber of the present invention, the content of the (meth) acrylate monomer unit is usually 50 to 99.9% by weight, preferably 60 to 99.5% by weight, and most preferably 70 to 99.5% by weight. If the content of the (meth) acrylate monomer unit is too small, the weather resistance, heat resistance, and oil resistance of the obtained rubber crosslinked product may be reduced; on the other hand, if it is too large, the obtained rubber crosslink may be reduced. The heat resistance of the material may be reduced.

In addition, in the acrylic rubber of the present invention, as the (meth) acrylate monomer unit, 30 to 100% by weight of the (meth) acrylate alkyl monomer unit and 70 to 0% by weight of the (meth) acrylate monomer unit are used. ) The alkoxyalkyl acrylate monomer unit is preferably formed.

The acrylic rubber of the present invention may contain a crosslinkable monomer unit in addition to the alkyl (meth) acrylate monomer unit as necessary. The crosslinkable monomer forming the crosslinkable monomer unit is not particularly limited, but examples include: α, β-ethylene unsaturated carboxylic acid monomers; monomers having an epoxy group; monomers having a halogen atom Body; diene monomer; etc.

The α, β-ethylene unsaturated carboxylic acid monomer forming an α, β-ethylene unsaturated carboxylic monomer unit is not particularly limited, but examples thereof include α, β-ethylene unsaturated having 3 to 12 carbon atoms. A monocarboxylic acid, an α, β-ethylene unsaturated dicarboxylic acid having 4 to 12 carbons, and an α, β-ethylene unsaturated dicarboxylic acid having 4 to 12 carbons, and an alkanol having 1 to 8 carbons Monoesters formed. By using an α, β-ethylene unsaturated carboxylic monomer, an acrylic rubber can be made into a carboxyl-containing acrylic rubber having a carboxyl group as a crosslinking point, and thus, in the case of being a rubber crosslinked product, it can be more Improve compression resistance.

Specific examples of the α, β-ethylene unsaturated monocarboxylic acid having 3 to 12 carbon atoms include acrylic acid, methacrylic acid, α-ethylacrylic acid, crotonic acid, and cinnamic acid.

Specific examples of the α, β-ethylene unsaturated dicarboxylic acid having 4 to 12 carbon atoms include butenedioic acids such as fumaric acid and maleic acid; itaconic acid; citraconic acid; Chloromaleic acid; etc.

Specific examples of monoesters formed from α, β-ethylene unsaturated dicarboxylic acids having 4 to 12 carbons and alkanols having 1 to 8 carbons include monomethyl fumarate ), Monoethyl fumarate, mono-n-butyl fumarate, mono-methyl maleate, mono-ethyl maleate, mono-n-butyl maleate, etc. Monoalkylene alkylates; monocyclopentyl fumarate, fumarate, fumarate, fumarate, fumarate, fumarate, fumarate Cyclopentyl esters, maleic acid monocyclohexyl esters, maleic acid monocyclohexyl esters and the like, butadionic acid monoesters having an alicyclic structure; itaconic acid monomethyl ester, Iconic acid monoesters such as monoethyl iconate, mono-n-butyl iconate, and monocyclohexyl iconate; etc.

Among them, monoesters of α, β-ethylene unsaturated dicarboxylic acids having 4 to 12 carbons and alkanols having 1 to 8 carbons are preferred, and butadiene mono-chain alkyl esters or alicyclic rings are preferred. Structures of butenedioic acid monoester are preferred, and fumaric acid mono-n-butyl ester, maleic acid mono-n-butyl ester, fumaric acid monocyclohexyl ester, and maleic acid mono-ester Cyclohexyl esters are more preferred, and fumaric acid mono-n-butyl ester is particularly preferred. These α, β-ethylene unsaturated carboxylic monomers may be used singly or in combination of two or more kinds. In addition, among the above-mentioned monomers, dicarboxylic acids also include those existing as an anhydride.

The monomer having an epoxy group is not particularly limited, but examples thereof include epoxy-containing (meth) acrylates such as glycidyl (meth) acrylate; allyl glycidyl ether; and Epoxy-containing ethers such as vinyl glycidyl ether; etc.

The monomer having a halogen atom is not particularly limited, but examples thereof include unsaturated alcohol esters of halogen-containing saturated carboxylic acids, haloalkyl (meth) acrylates, and halooxyalkyl (meth) acrylates ( haloacyloxyalkyl (meth) acrylate), (haloacetylcarbamoyloxy) alkyl (meth) acrylate, unsaturated ethers containing halogens, unsaturated ketones containing halogens, Aromatic vinyl compounds containing halogenated methyl groups, unsaturated halogenated amines containing halogens, unsaturated monomers containing halogenated ethylfluorene groups, and the like.

Specific examples of the unsaturated alcohol ester of a halogen-containing saturated carboxylic acid include vinyl chloroacetate, vinyl 2-chloropropionate, and allyl chloroacetate.

Specific examples of the haloalkyl (meth) acrylate include chloromethyl (meth) acrylate, 1-chloroethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, and (meth) ) 1,2-dichloroethyl acrylate, 2-chloropropyl (meth) acrylate, 3-chloropropyl (meth) acrylate, and 2,3-dichloropropyl (meth) acrylate.

Specific examples of the halooxyalkyl halide (meth) acrylate include 2- (chloroethylfluorenyloxy) ethyl (meth) acrylate, and 2- (chloroethanyloxy) propyl (meth) acrylate. Esters, 3- (chloroethylacetoxy) propyl (meth) acrylate, and 3- (hydroxychloroethylacetoxy) propyl (meth) acrylate.

Specific examples of the (meth) acrylic acid (halogenated ethylamidomethylformoxy) alkyl ester include 2- (chloroethylamidomethylformoxy) ethyl (meth) acrylate, and (formyl) (Meth) acrylic acid 3- (chloroethylfluorenylaminomethylmethoxy) propyl and the like.

Specific examples of the halogen-containing unsaturated ether include chloromethyl vinyl ether, 2-chloroethyl vinyl ether, 3-chloropropyl vinyl ether, 2-chloroethylallyl ether, and 3-chloropropyl allyl ether and the like.

Specific examples of the halogen-containing unsaturated ketone include 2-chloroethyl vinyl ketone, 3-chloropropyl vinyl ketone, and 2-chloroethyl allyl ketone.

Specific examples of the halogenated methyl-containing aromatic vinyl compound include p-chloromethylstyrene, m-chloromethylstyrene, o-chloromethylstyrene, and p-chloromethyl-α-methylstyrene.

Specific examples of the halogen-containing unsaturated fluorenamine include N-chloromethyl (meth) acrylamide and the like.

Specific examples of the unsaturated monomer containing a halogenated acetamyl group include 3- (hydroxychloroethylacetoxy) propylallyl ether, p-vinylbenzyl chloroacetate, and the like .

Examples of the diene monomer include a conjugated diene monomer and a non-conjugated diene monomer.

Specific examples of the conjugated diene monomer include 1,3-butadiene, isoprene, and 1,3-pentadiene.

Specific examples of the non-conjugated diene monomer include ethylidene norbornane, cyclopentadienyl, and dicyclopentadienyl (meth) acrylate. (meth) acrylate), 2-dicyclopentadienylethyl (meth) acrylate, and the like.

Even among the above-mentioned crosslinkable monomers, when an α, β-ethylene unsaturated carboxylic acid monomer is used, an acrylic rubber can be used as the acrylic rubber containing a carboxyl group. By using an acrylic rubber as an acrylic rubber containing a carboxyl group, it is possible to be an oil-resistant and heat-resistant one, and at the same time to improve compression resistance and permanent deformation, it is preferable. Further, as described later, the effect of the present invention is the case where an acrylic rubber is used as an acrylic rubber containing a carboxyl group compared to a case where a crosslinkable group (for example, an epoxy group, a halogen atom, etc.) other than a carboxyl group is introduced. The effect can be more significant, so from this point of view, acrylic rubber containing a carboxyl group is also preferable.

In the acrylic rubber of the present invention, the content of the crosslinkable monomer unit is preferably 0.1 to 10% by weight, more preferably 0.5 to 7% by weight, and even more preferably 0.5 to 5% by weight. By setting the content of the crosslinkable monomer unit to the above range, the mechanical properties and heat resistance of the obtained rubber crosslinked product are good, and at the same time, the compression set resistance can be more appropriately improved.

The acrylic rubber of the present invention may have, in addition to the (meth) acrylate monomer unit and the crosslinkable monomer unit used as necessary, units of other monomers capable of being copolymerized therewith. Examples of such other copolymerizable monomers include aromatic vinyl monomers, α, β-ethylene unsaturated nitrile monomers, acrylamide-based monomers, and other olefin-based monomers.

Examples of the aromatic vinyl monomer include styrene, α-methylstyrene, and divinylbenzene.

Examples of the α, β-ethylene unsaturated nitrile monomers include acrylonitrile and methacrylonitrile.

Examples of the acrylamide-based monomer include acrylamide, methacrylamide, and the like.

Examples of other olefin-based monomers include ethylene, propylene, vinyl chloride, vinylidene chloride, vinyl acetate, ethyl vinyl ether, and butyl vinyl ether.

Among other monomers capable of being copolymerized, styrene, acrylonitrile, methacrylonitrile, ethylene, and vinyl acetate are preferred, and acrylonitrile, methacrylonitrile, and ethylene are preferred.

Other copolymerizable monomers may be used alone or in combination of two or more. In the acrylic rubber of the present invention, the content of units capable of copolymerizing other monomers is usually 49.9% by weight or less, preferably 39.5% by weight or less, and most preferably 29.5% by weight or less.

In addition, the acrylic rubber of the present invention may be appropriately contained in a lubricant (hereinafter, referred to as a “specific lubricant” as appropriate) selected from at least one selected from the group consisting of phosphate esters, fatty acid esters, fatty acid esters, and higher fatty acids. As a result, the tackiness is reduced, and as a result, an acrylic rubber having excellent handleability and roll processability during drying can be obtained. Specifically, according to the acrylic rubber of the present invention, the following effects can be exhibited: the acrylic rubber can be effectively suppressed from being softened and adhered to the wall surface of the drying device due to the temperature during drying, thereby effectively suppressing the acrylic rubber against the drying device. The workability caused by the adhesion of the wall surface and the like is reduced; in addition, it is possible to effectively suppress the sticking to the roller when the roller is used and various admixtures are blended, thereby improving the processability when processing using the roller. In particular, in the case where an acrylic rubber is used as an acrylic rubber containing a carboxyl group, the compressive permanent deformation resistance can be appropriately improved by introducing a carboxyl group. On the other hand, the adhesiveness is increased by the action of a carboxyl group. In addition, in the case where an acrylic rubber containing a carboxyl group is used as the acrylic rubber, the adhesiveness is high, and compared with the case where a crosslinkable group (for example, an epoxy group, a halogen atom, etc.) other than the carboxyl group is introduced, the The problem of adhesion to the wall surface of the drying device, etc., and the problem of adhesion to the roller when using a roller and blending various admixtures become more significant. According to the present invention, these problems can be effectively solved even in the case where an acrylic rubber containing a carboxyl group is used.

The acrylic rubber of the present invention may be a lubricant containing at least one selected from the group consisting of phosphate esters, fatty acid esters, fatty acid amines, and higher fatty acids. However, among these, it is necessary to include a lubricant selected from phosphate esters and higher fatty acids. At least one lubricant is preferred.

Examples of the phosphate include polyoxyethylene stearylether phosphate, polyoxyethylene lauryl ether phosphate, polyoxyethylene oleyl ether phosphate, and polyoxyethylene oleyl ether phosphate. Polyoxyethylene higher alcohol phosphates such as polyoxyethylene tridecyl ether phosphate. Among them, polyoxyethylene stearyl ether phosphate is preferred. Further, the higher fatty acid is preferably a fatty acid having 12 to 20 carbon atoms, and a fatty acid having 13 to 19 carbon atoms is preferred. As the higher fatty acid, a mixture of a plurality of higher fatty acids having different carbon numbers may also be used.

In the acrylic rubber of the present invention, the content of the specific lubricant is preferably 0.1 to 0.4% by weight, more preferably 0.15 to 0.3% by weight, and even more preferably 0.2 to 0.3% by weight. When the content of the specific lubricant is within the above range, the occurrence of bleeding can be suppressed, and at the same time, the handleability and roll workability during drying can be more effectively improved. In addition, an acrylic rubber can be dissolved in tetrahydrofuran, and tetrahydrofuran can be used as a developing solvent to perform GPC measurement to obtain the content of a specific lubricant. Specifically, from the chart obtained by GPC measurement, the integral 値 of the peak corresponding to the molecular weight of the specific lubricant is obtained, and the integral 値 of the peak 丙烯酸 and the peak of the acrylic rubber is compared.値 Corresponding molecular weight, the weight ratio is obtained, and the specific lubricant content is obtained.

In addition, as described above, the acrylic rubber of the present invention contains a specific lubricant, but in the acrylic rubber of the present invention, the content of the acrylic rubber component is preferably 95% by weight or more, more preferably 97% by weight or more, It is more preferably 98% by weight or more. That is, the acrylic rubber of the present invention may also be a composition of an acrylic rubber containing an acrylic rubber component that is preferably 95% by weight or more (more preferably 97% by weight or more, and more preferably 98% by weight or more).

<Manufacturing method of acrylic rubber>

The acrylic rubber of the present invention can be produced by, for example, the following production method. That is, it can be manufactured by a method for manufacturing an acrylic rubber having the following steps: An emulsification polymerization step is performed by emulsifying and polymerizing a monomer for forming an acrylic rubber, thereby obtaining an emulsified polymerization solution; A specific lubricant is contained in the emulsion polymerization solution before the aggregation is performed; and a coagulation step is performed by adding a coagulant to the emulsion polymerization solution and aggregating it, thereby obtaining water-containing pellets.

In addition, in the above manufacturing method, the above-mentioned emulsification polymerization step may be set as follows: a monomer for forming an acrylic rubber is mixed with an emulsifier and water in advance to obtain a monomer emulsion (emulsion preparation) Step), performing emulsification polymerization (emulsion polymerization step) in the state of the obtained monomer emulsion. In this state, it can also be set as follows: After adding a specific lubricant to the monomer emulsion, Emulsion polymerization is performed.

<Emulsion polymerization step>

In the manufacturing method of the present invention, the emulsion polymerization step is a step of emulsion-polymerizing a monomer for forming an acrylic rubber, thereby obtaining an emulsion polymerization solution.

As the emulsification polymerization method in the emulsification polymerization step, an ordinary method may be used, and an emulsifier, a polymerization initiator, a polymerization terminator, or the like may be used in accordance with a conventional method.

The emulsifier is not particularly limited, and examples thereof include polyoxyethylene alkyl ethers such as polyoxyethylene dodecyl ether, and polyoxyethylene nonylphenyl ether. Polyoxyethylene alkylphenol ether, polyoxyethylene stearate, etc. Polyoxyethylene alkyl ester, Polyoxyethylene sorbitan alkyl ester), polyoxyethylene polyoxypropylene copolymer and other nonionic emulsifiers; myristic acid, palmitic acid, oleic acid, hypolinolenic acid and other fatty acid salts, dodecylbenzenesulfonic acid Alkylbenzene sulfonates such as sodium dodecylbenzenesulfonate, higher alcohol sulfates such as sodium lauryl sulfate, higher phosphate salts such as sodium alkyl phosphate, alkyl sulfosuccinate ) And other anionic emulsifiers; alkyltrimethyla chloride mmonium chloride), dialkyl ammonium chloride, benzyl ammonium chloride and other cationic emulsifiers; etc. These emulsifiers can be used alone or in combination of two or more. Among these non-ionic emulsifiers are polyoxyethylene polypropylene glycol, polyethylene glycol monostearate, polyoxyethylene alkyl ether, and polyoxyethylene alkyl phenol ether. Better. In addition, as the nonionic emulsifier, a weight average molecular weight of less than 10,000 is preferable, a weight average molecular weight of 500 to 8000 is more preferable, and a weight average molecular weight of 600 to 5000 is more preferable. Among these anionic emulsifiers, higher phosphate salts and higher alcohol sulfate salts are preferred.

Among these emulsifiers, at least one of a nonionic emulsifier and an anionic emulsifier is preferable, and at least an anionic emulsifier is preferably contained. A nonionic emulsifier is combined with an anionic emulsifier. It is better to use. By using a combination of a nonionic emulsifier and an anionic emulsifier, it is possible to effectively suppress the occurrence of fouling caused by adhesion of a polymer, etc., to a polymerization device (such as a polymerization tank) during emulsion polymerization, and to reduce simultaneously the later-mentioned The amount of the coagulant used in the coagulation step can reduce the amount of coagulant in the finally obtained acrylic rubber, thereby improving the water resistance of the obtained rubber crosslinked product.

In addition, by combining and using a nonionic emulsifier and an anionic emulsifier, the emulsification effect can be improved, so the amount of emulsifier itself can be reduced, and as a result, the emulsifier contained in the finally obtained acrylic rubber can be reduced. The residual amount of this can further improve the water resistance of the acrylic rubber obtained.

In the manufacturing method of the present invention, based on the total amount of the emulsifier used, the amount of the emulsifier used is preferably 0.1 to 5 parts by weight, and 0.5 to 4 parts by weight relative to 100 parts by weight of the monomer used in the polymerization. Parts are more preferred, and 1 to 3 parts by weight are more preferred. When a non-ionic emulsifier and an anionic emulsifier are used in combination, the amount of the non-ionic emulsifier is more than 0 parts by weight and 4 parts by weight based on 100 parts by weight of the monomer used for polymerization. It is preferably 0.1 to 3 parts by weight, more preferably 0.5 to 2 parts by weight, more preferably 0.7 to 1.7 parts by weight, and 100 parts by weight of the monomer used for polymerization. The amount used is more than 0 parts by weight and 4 parts by weight or less, preferably 0.1 to 3 parts by weight, more preferably 0.5 to 2 parts by weight, and even more preferably 0.35 to 0.75 parts by weight. When a nonionic emulsifier and an anionic emulsifier are used in combination, the use ratio is based on the weight ratio of the nonionic emulsifier / anionic emulsifier and the ratio is 1/99 to 99/1. 10/90 to 80/20 is preferred, 25/75 to 75/25 is more preferred, 50/50 to 75/25 is even more preferred, and 65/35 to 75/25 is particularly preferred.

As the polymerization initiator, azo compounds such as azobisisobutyronitrile can be used; organic peroxides such as dicumyl hydroperoxide, cumene hydroperoxide, p-menthane hydroperoxide, and benzoylperoxide. Substances; inorganic peroxides such as sodium persulfate, potassium persulfate, hydrogen peroxide, ammonium persulfate; etc. These polymerization initiators can be used alone or in combination of two or more kinds. The amount of the polymerization initiator used is preferably 0.001 to 1.0 parts by weight based on 100 parts by weight of the monomers used for polymerization.

The organic peroxide and the inorganic peroxide as the polymerization initiator are preferably used as a redox polymerization initiator in combination with a reducing agent. The reducing agent used in combination is not particularly limited, but examples include compounds containing reduced metal ions such as ferrous sulfate, sodium hexamethylenediamine tetraacetate, and copper (II) naphthenate; ascorbic acid and ascorbic acid Ascorbic acid (salt) such as sodium, potassium ascorbate; erythorbic acid (salt) such as erythorbic acid, sodium erythorbic acid, potassium erythorbic acid; saccharides; sodium sulfamate such as hydroxymethanesulfinate; sodium sulfite, potassium sulfite, and sulfurous acid Sodium bisulfite, aldehyde-sodium bisulfite, potassium bisulfite; bisulphite, sodium metabisulfite, potassium metabisulfite, sodium metabisulfite, potassium metabisulfite, etc .; Thiosulfates such as sodium thiosulfate and potassium thiosulfate; Phosphorous acid (salt) of phosphorous acid, sodium phosphite, potassium phosphite, sodium hydrogen phosphite, potassium hydrogen phosphite; pyrophosphoric acid, sodium pyrophosphite , Potassium pyrophosphite, sodium pyrophosphite, potassium pyrophosphite and other pyrophosphates (salts); sodium formaldehyde sulfoxylate and so on. These reducing agents may be used alone or in combination of two or more. The amount of the reducing agent used is preferably 0.0003 to 0.5 parts by weight with respect to 100 parts by weight of the monomers used in the polymerization.

Examples of the polymerization terminator include osmium, osmium sulfate, diethylamidine, bis (hydroxylamine) sulfonate and alkali metal salts thereof, sodium dimethyldithiocarbamate, and hydroquinone. The amount of the polymerization terminator used is not particularly limited, but it is preferably from 0.1 to 2 parts by weight based on 100 parts by weight of the monomer used for the polymerization.

The amount of water used is preferably 80 to 500 parts by weight, and more preferably 100 to 300 parts by weight with respect to 100 parts by weight of the monomers used for polymerization.

In the emulsion polymerization, if necessary, a polymerization auxiliary material such as a molecular weight adjuster, a particle size adjuster, a chelating agent, and an oxygen trapping agent can be used.

Emulsion polymerization can be performed by any of a batch method, a semi-batch method, and a continuous method, but a semi-batch method is preferred. Specifically, it is preferred that at least one of a monomer, a polymerization initiator, and a reducing agent used in the polymerization is continuously dropped to the polymerization reaction system and the polymerization reaction is performed simultaneously from the start of the polymerization reaction to an arbitrary time. For example, in a reaction system containing a polymerization initiator and a reducing agent, from the start of the polymerization reaction to an arbitrary time, the monomers used in the polymerization are continuously dropped to the polymerization reaction system and the polymerization reaction is performed simultaneously; more preferably, since The polymerization reaction is started to an arbitrary time, and the monomers, polymerization initiator, and reducing agent used for the polymerization are continuously dropped into the polymerization reaction system and the polymerization reaction is performed. By continuously dropping these and simultaneously carrying out the polymerization reaction, the emulsion polymerization can be stably performed, whereby the polymerization reaction rate can be improved. The polymerization system is usually carried out at a temperature ranging from 0 to 70 ° C, preferably from 5 to 50 ° C.

In addition, in the case where the monomers used for polymerization are continuously dropped and the polymerization reaction is performed simultaneously, it is preferable to mix the monomers used for polymerization with an emulsifier and water to obtain a monomer emulsion (emulsion preparation step) Continuous dripping in the state of monomer emulsion. The method for preparing the monomer emulsion is not particularly limited, and examples thereof include using a homomixer or a disk turbine to stir the entire amount of the monomers used in the polymerization and the total amount of the emulsifier. And how to stir water. The amount of water used in the monomer emulsion is preferably 10 to 70 parts by weight, and more preferably 20 to 50 parts by weight, with respect to 100 parts by weight of the monomer used for polymerization.

In addition, in the case where the monomer, the polymerization initiator, and the reducing agent used for the polymerization are continuously dropped to the polymerization reaction system and the polymerization reaction is performed simultaneously from the start of the polymerization reaction to an arbitrary time, each of these can be used It may be dropped into the polymerization system by another dropping device, or at least a polymerization initiator and a reducing agent may be mixed in advance, and if necessary, it may be dropped into the polymerization system from the same dropping device in the state of an aqueous solution. After the dropping is completed, in order to further increase the polymerization reaction rate, the reaction may be continued for an arbitrary time.

＜ Specific lubricant addition procedure ＞

The specific lubricant addition step of the production method of the present invention is a step of including the specific lubricant in the emulsified polymerization solution before the aggregation.

The method for including the specific lubricant in the emulsified polymerization solution is not particularly limited, and any method may be used as long as the emulsified polymerization solution before aggregation can be made into a state containing the specific lubricant. For example, a specific lubricant may be added to the emulsion polymerization solution after the emulsion polymerization, or it may be in the solution before the emulsion polymerization, specifically, in a solution for emulsion polymerization (for example, to be used to form The monomer emulsion of acrylic rubber is mixed with an emulsifier and water to obtain a monomer emulsion), a specific lubricant is added, and emulsification polymerization is performed in the presence of the specific lubricant to obtain a specific lubricant. Emulsion polymerization solution. Among them, from the viewpoint that the effect of the present invention can be further enhanced, it is preferable to adopt a state in which a specific lubricant is added to the emulsion polymerization solution after the emulsion polymerization. In addition, the added form of the specific lubricant is not particularly limited, but in the case where the specific lubricant is solid at normal temperature, it may be added directly in a solid state, or it may be added in a melted state.

According to the manufacturing method of the present invention, the specific emulsifier is contained in the emulsified polymerization solution before the aggregation, so that the specific lubricant can be well dispersed in the emulsified polymerization solution before the aggregation. The acrylic rubber contains a specific lubricant in a state where it can be dispersed well. Furthermore, as a result, the obtained acrylic rubber can appropriately contain a specific lubricant (preferably, it can be contained in a state where it is uniformly dispersed), whereby the obtained acrylic rubber can be used as a handleability and roller during drying. Those with excellent processability. In addition, even in the case where a specific lubricant is contained in the emulsified polymerization solution before the aggregation, the specific lubricant added in subsequent aggregation, washing, drying, etc. will not be substantially removed, so it is sufficient. Play its added effect. On the other hand, when a specific lubricant is added after agglomeration, it becomes difficult to disperse the specific lubricant in the acrylic rubber, so that the specific lubricant cannot be contained in the acrylic rubber (especially, it cannot be contained in a uniformly dispersed state). As a result, it becomes impossible to obtain the effect caused by blending a specific lubricant, that is, it becomes impossible to obtain the effect of improving the handleability and roll processability during drying.

In the specific lubricant adding step, the amount of the specific lubricant added is not particularly limited, as long as it is set to an amount corresponding to the amount contained in the obtained acrylic rubber, but it is relative to 100 weight of the acrylic rubber component in the emulsion polymerization solution. It is preferably 0.1 to 0.4 parts by weight, more preferably 0.15 to 0.3 parts by weight, and even more preferably 0.2 to 0.3 parts by weight.

In addition, in the manufacturing method of the present invention, in addition to the specific lubricant, it is preferable that the emulsification polymerization solution before the aggregation is contained in advance as a blending agent containing a part of the blending agent blended with acrylic rubber. Specifically, the admixture is an anti-aging agent and / or an ethylene oxide polymer.

For example, by containing an anti-aging agent in the emulsified polymerization solution before the aggregation, the deterioration of the acrylic rubber due to heat during drying in the drying step described later can be effectively suppressed. Specifically, it can effectively suppress the decrease in Mooney viscosity due to the deterioration caused by heating during drying, thereby effectively improving the normal tensile strength when used as a rubber crosslinked product. Or elongation at break. In addition, in the state of the emulsified polymerization solution before the aggregation, the anti-aging agent can be appropriately dispersed by blending the anti-aging agent. Therefore, even when the amount of the anti-aging agent is reduced, it can be used. Give full play to its added effect. Specifically, the amount of the anti-aging agent is preferably 0.1 to 2 parts by weight, and more preferably 0.2 to 1.2 parts by weight relative to 100 parts by weight of the acrylic rubber component in the emulsion polymerization solution. The blending amount can also give full play to its added effect. In addition, even when the anti-aging agent is contained in the emulsified polymerization solution before the aggregation, the anti-aging agent added in the subsequent aggregation, washing, and drying is not substantially removed, so that the anti-aging agent can be fully utilized. Add effects. In addition, as a method for containing an anti-aging agent in the emulsion polymerization solution, a method of adding to the emulsion polymerization solution after the emulsion polymerization and before the aggregation is performed, and a method of adding the solution to the solution before the emulsion polymerization are performed, In the case of a solution before polymerization, agglomerates are generated during the emulsion polymerization, and therefore, there is a possibility that dirt or the like may be generated in the polymerization apparatus. Therefore, it is preferable to add the emulsion polymerization solution after the emulsion polymerization and before the aggregation.

The anti-aging agent is not particularly limited, but examples thereof include 4-methyl-2,6-bis-tertiary butylphenol, 2,6-bis-tertiary butylphenol, butylhydroxymethoxybenzene, 2,6- Bis-tertiary butyl-α-dimethylamino-p-cresol, 3- (3,5-bis-tertiary butyl-4-hydroxyphenyl) propanoic acid octadecyl ester (octadecyl-3- (3,5 -di-t-butyl-4-hydroxyphenyl) propionate), styrenated phenol, 2,2'-methylenebis (6-α-methyl-benzyl-p-cresol), 4,4'-methylene Bis (2,6-bis-tertiary butylphenol), 2,2'-methylenebis (4-methyl-6-tertiary butylphenol), 3- (3,5-bistertiary butyl-4- Butyl reaction of stearyl 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, alkylated bisphenol, p-cresol and dicyclopentadiene Products such as sulfur-free phenolic anti-aging agents; 2,4-bis [(octylthio) methyl] -6-methylphenol, 2,2'-thiobis- (4-methyl-6 -Tertiary butyl phenol), 4,4'-thiobis- (6-tertiary butyl o-cresol), 2,6-bis tertiary butyl-4- (4,6-bis (octylthio) Thiophenol-based anti-aging agents such as -1,3,5-tri-2-ylamino) phenol; tris (nonylphenyl) phosphite, diphenylisodecyl phosp hite), tetraphenyl dipropylene glycol diphosphite and other phosphite-based anti-aging agents; thioester-based dilauryl thioester-based anti-aging agents; phenyl-α-naphthylamine , Phenyl-β-naphthylamine, p- (p-toluenesulfonamide) diphenylamine, 4,4 '-(α, α-dimethylbenzyl) diphenylamine, N, N-diphenylp-phenylenediamine , N-isopropyl-N'-phenyl-p-phenylenediamine, butyraldehyde-aniline condensate and other amine-based anti-aging agents; 2-mercapto-benzimidazole and other imidazole-based anti-aging agents; 2,2,4- Quinoline anti-aging agents such as trimethyl-6-ethoxy-1,2-dihydroquinoline; hydroquinone anti-aging agents such as 2,5-di- (tripentyl) hydroquinone; etc. These anti-aging agents may be used alone or in combination of two or more.

In addition, by preliminarily containing an ethylene oxide polymer in the emulsified polymerization solution before aggregation, the cohesiveness of the emulsified polymerization solution can be improved, thereby reducing the amount of agglomeration in the agglomeration step, and thus reducing the amount of acrylic rubber in the finally obtained acrylic rubber. Residual amount, when used as a rubber cross-linked product, can further improve compression resistance and water resistance. The ethylene oxide polymer is not particularly limited as long as it is a polymer having a polyethylene oxide structure as a main chain structure, but examples thereof include polyethylene oxide, polyoxypropylene, and an ethylene oxide / propylene oxide copolymer. Among them, polyethylene oxide is preferred. The blending amount of the ethylene oxide-based polymer is preferably 0.01 to 1 part by weight, more preferably 0.01 to 0.6 part by weight, and 0.02 to 0.5 part by weight based on 100 parts by weight of the acrylic rubber component in the emulsion polymerization solution. Better. The weight average molecular weight of the ethylene oxide-based polymer is preferably 10,000 to 1 million, more preferably 10,000 to 200,000, and even more preferably 20,000 to 120,000. In addition, examples of a method for containing an ethylene oxide polymer in the emulsion polymerization solution include a method of adding to the emulsion polymerization solution after the emulsion polymerization and before aggregation, and a method of adding the solution to the solution before emulsion polymerization.

In addition, in the case where an anti-aging agent and / or an ethylene oxide-based polymer are added to the emulsified polymerization solution before the aggregation, the addition order is not particularly limited as long as it is appropriately selected.

＜ Coagulation step ＞

In the production method of the present invention, the agglomeration step is a step of obtaining a water-containing pellet by adding a coagulant to the emulsion polymerization solution obtained by the above-mentioned emulsion polymerization step.

Although it does not specifically limit as an aggregating agent, For example, a 1- to trivalent metal salt is mentioned. The 1 to 3 valence metal salt is a salt containing a metal that becomes a 1 to 3 valence metal ion when dissolved in water. Although not particularly limited, examples thereof include inorganic acids selected from hydrochloric acid, nitric acid, and sulfuric acid. Or a salt of an organic acid such as acetic acid and a metal selected from the group consisting of sodium, potassium, lithium, magnesium, calcium, zinc, titanium, manganese, iron, cobalt, nickel, aluminum, and tin. In addition, hydroxides of these metals can also be used.

Specific examples of the 1- to 3-valent metal salt include sodium chloride, potassium chloride, lithium chloride, magnesium chloride, calcium chloride, zinc chloride, titanium chloride, manganese chloride, iron chloride, and chlorine. Cobalt, nickel chloride, aluminum chloride, tin chloride and other metal chlorides; sodium nitrate, potassium nitrate, lithium nitrate, magnesium nitrate, calcium nitrate, zinc nitrate, titanium nitrate, manganese nitrate, iron nitrate, cobalt nitrate, nitric acid Nitrates such as nickel, aluminum nitrate, tin nitrate; sodium sulfate, potassium sulfate, lithium sulfate, magnesium sulfate, calcium sulfate, zinc sulfate, titanium sulfate, manganese sulfate, iron sulfate, cobalt sulfate, nickel sulfate, aluminum sulfate, tin sulfate, etc. Sulfate; etc. Among these, calcium chloride, sodium chloride, aluminum sulfate, magnesium chloride, magnesium sulfate, zinc chloride, zinc sulfate, and sodium sulfate are preferred. Among them, monovalent or divalent metal salts are preferred, calcium chloride, sodium chloride, magnesium sulfate, sodium sulfate is more preferred, and magnesium sulfate or sodium sulfate is more preferred. And, these may be used singly or in combination.

Acrylic rubber can fully agglomerate and at the same time reduce the residual amount of agglomerating agent in the finally obtained acrylic rubber. Thus, in the case of being a rubber crosslinked product, from the viewpoint of improving compression permanent deformation resistance and water resistance, In other words, with respect to 100 parts by weight of the acrylic rubber component in the emulsion polymerization solution, the amount of the coagulant used is preferably 1 to 100 parts by weight, more preferably 2 to 40 parts by weight, and even more preferably 3 to 20 parts by weight. It is particularly preferably 3 to 12 parts by weight.

The aggregation temperature is not particularly limited, but is preferably 50 to 90 ° C, and more preferably 60 to 90 ° C.

＜ Cleaning steps ＞

In the manufacturing method of the present invention, it is preferable to further include a washing step of washing the water-containing pellets obtained in the coagulation step.

The washing method is not particularly limited, but a method of washing with water by using water as the washing liquid and mixing the water-containing pellets with the added water is mentioned. The temperature during water washing is not particularly limited, but is preferably 5 to 60 ° C, more preferably 10 to 50 ° C, and a mixing time of 1 to 60 minutes, and more preferably 2 to 30 minutes.

In addition, the amount of water added to the water-containing pellets during water washing is not particularly limited, but from the viewpoint of effectively reducing the residual amount of the coagulant in the acrylic rubber finally obtained, it is relative to the amount contained in the water-containing pellets. The solid content (mainly an acrylic rubber component) is 100 parts by weight, and the amount of water per one wash is preferably 50 to 9,800 parts by weight, and more preferably 300 to 1,800 parts by weight.

The number of times of water washing is not particularly limited, and may be one time, but from the viewpoint of reducing the remaining amount of the coagulant in the acrylic rubber finally obtained, it is preferably 2 to 10 times, and more preferably 3 to 8 times. In addition, from the viewpoint of reducing the residual amount of the flocculant in the finally obtained acrylic rubber, it is preferable that the number of times of washing with water is large. The effect of decreasing the productivity due to an increase in the number of steps becomes larger, so the number of washing cycles is preferably set to the above range.

Further, in the present invention, acid washing using an acid as a cleaning solution may be performed after water washing. By performing acid cleaning, in the case of being used as a rubber cross-linked product, compression resistance can be further improved. In the case where acrylic rubber is a carboxyl-containing acrylic rubber having a carboxyl group, compression resistance caused by the acid cleaning The effect of improving the permanent deformability is particularly great. The acid used for the acid cleaning is not particularly limited, and sulfuric acid, hydrochloric acid, phosphoric acid, and the like can be used without limitation. In addition, in the acid cleaning, when the acid is added to the water-containing pellets, it is preferably added in the state of an aqueous solution, and is preferably added in the state of an aqueous solution of pH = 6 or less, and more preferably pH = 4 or less. Below pH = 3 is even better. The method of acid cleaning is not particularly limited, and examples thereof include a method of mixing water-containing pellets with an aqueous solution of an acid to be added.

The temperature during acid cleaning is not particularly limited, but is preferably 5 to 60 ° C, more preferably 10 to 50 ° C, and a mixing time of 1 to 60 minutes, and more preferably 2 to 30 minutes. The pH of the acid-washing washing water is not particularly limited, but is preferably pH = 6 or less, more preferably pH = 4 or less, and even more preferably pH = 3 or less. The pH of the washing water for acid washing can be determined, for example, by measuring the pH of water contained in the water-containing pellets after the acid washing.

After acid washing, it is preferable to perform water washing again, and the conditions for water washing may be the same as those described above.

＜ Drying step ＞

Further, in the production method of the present invention, it is preferable to further include a drying step of drying the water-containing pellets washed in the washing step.

The drying method in the drying step is not particularly limited, but drying can be performed using, for example, a screw-type extruder, a kneading-type dryer, an expander dryer, a hot-air dryer, or a reduced-pressure dryer. . Also, a combination of these drying methods can be used. Furthermore, before drying in the drying step, if necessary, the water-containing pellets may be subjected to a sieve such as a rotary sieve, a vibrating sieve, a centrifugal dehydrator, and the like.

For example, the drying temperature in the drying step is not particularly limited, and it depends on the dryer used for drying, but in the case of using a hot air dryer, for example, the drying temperature is preferably set to 80 to 200 ° C. It is preferable to set it to 100 to 170 ° C.

According to the manufacturing method of this invention, the acrylic rubber of this invention can be obtained as mentioned above.

The acrylic viscosity of the acrylic rubber of the present invention (ML1 + 4, 100 ° C) (polymer Mooney) is preferably 10 to 80, more preferably 20 to 70, and 25 ~ 60 is more preferable.

In the acrylic rubber of the present invention, the residual amount of the coagulant contained in the acrylic rubber is preferably 10,000 ppm by weight or less, more preferably 7,000 ppm by weight or less, more preferably 5,000 ppm by weight or less, and particularly 3,500 ppm. It is preferably below ppm. The lower limit of the remaining amount of the coagulant is not particularly limited, but it is preferably 10 ppm by weight or more. By setting the residual amount of the aggregating agent in the acrylic rubber to the above range, when it is used as a rubber crosslinked product, it can be made excellent in compression set resistance and water resistance. The remaining amount of the coagulant can be determined by, for example, performing elemental analysis on acrylic rubber and measuring the content of elements contained in the coagulant. In addition, the method of making the remaining amount of the aggregating agent into the above amount is not particularly limited, but examples thereof include a method of setting the amount of the aggregating agent in the above range, and a method of adjusting the washing conditions as described above.

Furthermore, the acrylic rubber of the present invention preferably has a residual amount of an emulsifier contained in the acrylic rubber of 22,000 ppm by weight or less, more preferably 20,000 ppm by weight or less, more preferably 18,000 ppm by weight or less, particularly It is preferably 17,000 ppm by weight or less. The lower limit of the residual amount of the emulsifier is not particularly limited, but it is preferably 10 ppm by weight or more, more preferably 200 ppm by weight or more, and even more preferably 500 ppm by weight or more. By setting the residual amount of the emulsifier in the acrylic rubber to the above range, when it is used as a rubber crosslinked product, water resistance can be further improved. In addition, for example, GPC measurement can be performed on acrylic rubber. In the measurement chart obtained by GPC measurement, the residual amount of the emulsifier can be determined from the peak area corresponding to the molecular weight of the emulsifier. In addition, the method of making the remaining amount of the emulsifier into the above amount is not particularly limited, but examples thereof include a combination of a nonionic emulsifier and an anionic emulsifier as described above and use as an emulsifier, and A method of setting the added amount to the above range, and the like.

＜ Acrylic rubber composition ＞

The acrylic rubber composition of the present invention is obtained by blending a crosslinking agent with the acrylic rubber of the present invention.

The crosslinking agent is not particularly limited, but, for example, polyvalent amine compounds such as diamine compounds and carbonates thereof; sulfur; sulfur donors; trithiol compounds; polyvalent epoxy compounds; organic carboxylic acid ammonium salts Organic peroxides; metal dithioamine formates; polycarboxylic acids; quaternary onium salts; imidazole compounds; isotricyanic acid compounds; organic peroxides; and other conventionally known crosslinking agents. These crosslinking agents may be used singly or in combination of two or more kinds. The cross-linking agent is preferably appropriately selected depending on the type of the cross-linkable monomer unit.

Among these, in the case where the acrylic rubber of the present invention has an α, β-ethylene unsaturated carboxylic monomer unit as a crosslinkable monomer unit, a polyvalent amine compound and a carbonate thereof are used as the crosslink Agent is better.

The polyvalent amine compound and its carbonate are not particularly limited, but a polyvalent amine compound having 4 to 30 carbon atoms and a carbonate thereof are preferred. Examples of such a polyvalent amine compound and its carbonate include an aliphatic polyvalent amine compound, its carbonate, and an aromatic polyvalent amine compound.

The aliphatic polyvalent amine compound and its carbonate are not particularly limited, but examples thereof include hexamethylenediamine, hexamethylenediamine carbamate, and N, N ' -N, N'-dicinnamylidene-1,6-hexanediamine, etc. Among these, hexamethylene diamine carbamate is preferred.

The aromatic polyvalent amine compound is not particularly limited, but examples thereof include 4,4'-methylenediphenylamine, p-phenylenediamine, m-phenylenediamine, and 4,4'-diaminodiphenyl. Ether, 3,4'-diaminodiphenyl ether, 4,4 '-(m-phenylenediisopropylidene) dianiline, 4,4 '-(P-phenylene diisopropylidene) diphenylamine, 2,2'-bis [4- (4-aminophenoxy) phenyl] propane (2,2'-bis [4- (4 -aminophenoxy) phenyl] propane), 4,4'-diaminobenzylamine benzene, 4,4'-bis (4-aminophenoxy) biphenyl, m-xylylenediamine, p-xylenexylene Amines, and 1,3,5-phenyltriamine. Among these, 2,2'-bis [4- (4-aminophenoxy) phenyl] propane is preferred.

The content of the crosslinking agent in the acrylic rubber composition of the present invention is preferably 0.05 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, and more preferably 0.2 to 4 parts by weight relative to 100 parts by weight of the acrylic rubber. good. By setting the content of the cross-linking agent to the above range, the rubber elasticity can be made sufficient and the mechanical strength can be made excellent as a rubber cross-linked product.

The acrylic rubber composition of the present invention preferably further contains a crosslinking accelerator. The cross-linking accelerator is not particularly limited, but the acrylic rubber of the present invention has a carboxyl group as a cross-linkable group, and when the cross-linking agent is a polyvalent amine compound or a carbonate thereof, guanidine may be used. Compounds, diazabicyclic olefin compounds, imidazole compounds, quaternary onium salts, tertiary phosphine compounds, aliphatic monovalent secondary amine compounds, aliphatic monovalent tertiary amine compounds, and the like. Among these, a guanidine compound, a diazabicyclic olefin compound, and an aliphatic monovalent secondary amine compound are preferable, and a guanidine compound is more preferable. These basic crosslinking accelerators may be used singly or in combination of two or more kinds.

Specific examples of the guanidine compound include 1,3-di-o-tolylguanidine, 1,3-diphenylguanidine, and the like. Specific examples of the diazabicyclic olefin compound include 1,8-diazabicyclo [5.4.0] undec-7-ene, 1,5-diazabicyclo [4.3.0] non-5-ene, and the like . Specific examples of the imidazole compound include 2-methylimidazole and 2-phenylimidazole. Specific examples of the quaternary onium salt include tetra-n-butylammonium bromide, octadecyltri-n-butylammonium bromide, and the like. Specific examples of the tertiary phosphine compound include triphenylphosphine and tri-p-toluylphosphine.

An aliphatic monovalent secondary amine compound is a compound in which two hydrogen atoms of ammonia are replaced by an aliphatic hydrocarbon group. The aliphatic hydrocarbon group substituted with a hydrogen atom is preferably one having 1 to 30 carbon atoms. Specific examples of the aliphatic monovalent secondary amine compound include dimethylamine, diethylamine, dipropylamine, diallylamine, diisopropylamine, di-n-butylamine, bis-tertiary butylamine, and bis-secondary butylamine. (Di-sec-butylamine), dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, diundecylamine, dodecylamine, ditridecylamine, ditetradecylamine , Dipentadecylamine, dihexadecylamine, di-2-ethylhexylamine, and dioctadecylamine.

An aliphatic monovalent tertiary amine compound is a compound in which all three hydrogen atoms of ammonia are replaced with an aliphatic hydrocarbon group. The aliphatic hydrocarbon group substituted with a hydrogen atom is preferably one having 1 to 30 carbon atoms. Specific examples of the aliphatic monovalent tertiary amine compound include trimethylamine, triethylamine, tripropylamine, triallylamine, triisopropylamine, tri-n-butylamine, tris (tertiary butyl) amine, and tris (di) Butyl) amine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, tri (undecyl) amine, and tris (dodecyl) amine.

In the acrylic rubber composition of the present invention, the content of the crosslinking accelerator is preferably 0.1 to 10 parts by weight relative to 100 parts by weight of the acrylic rubber, more preferably 0.5 to 7.5 parts by weight, and 1 to 5 parts by weight. Better. By setting the content of the crosslinking accelerator to the above range, the tensile strength and compression set resistance of the obtained rubber crosslinked product can be further improved.

In addition, the acrylic rubber composition of the present invention may be blended with admixtures generally used in the field of rubber processing in addition to the above-mentioned components. Examples of such admixtures include: reinforcing fillers such as silica or carbon black; non-reinforcing fillers such as calcium carbonate or clay; anti-aging agents; light stabilizers; anti-scorching agents; plasticizers; processing aids Agents; adhesives; lubricants; lubricants; flame retardants; antifungal agents; antistatic agents; colorants; crosslinking blockers; etc. The blending amount of these blending agents is not particularly limited as long as it does not interfere with the purpose and effect of the present invention, and an amount corresponding to the blending purpose may be appropriately blended.

Furthermore, in the acrylic rubber composition of the present invention, rubbers, elastomers, resins, and the like other than the above-mentioned acrylic rubber of the present invention may be further blended so long as the effects of the present invention are not impaired. For example, acrylic rubber other than the acrylic rubber of the present invention, natural rubber, polybutadiene rubber, polyisoprene rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, and silicone can be blended. Rubber other than acrylic rubber such as rubber, fluororubber; olefin elastomer, styrene elastomer, vinyl chloride elastomer, polyester elastomer, polyamide elastomer, polyurethane elastomer, polysiloxane Elastomers such as alkane-based elastomers; polyolefin resins, polystyrene resins, polyacrylic resins, polyphenylene ether resins, polyester resins, polycarbonate resins, polyamide resins, vinyl chloride resins Resins such as base resins, fluororesins; etc. In addition, with respect to 100 parts by weight of the acrylic rubber, the total blending amount of the rubber, elastomer and resin other than the acrylic rubber of the present invention is preferably 50 parts by weight or less, more preferably 10 parts by weight or less, and 1 part by weight Servings below are better.

The acrylic rubber composition of the present invention can be prepared by blending a crosslinking agent and other blending agents as needed in the acrylic rubber, and mixing them using a Banbury mixer, a kneader, and the like. , Kneading, and then use the kneading roller for further kneading.

The mixing order of each component is not particularly limited, but it is preferred that after sufficiently mixing the components that are difficult to cause reaction or decomposition under heat, the components that are liable to react or decompose under heat will not cause reaction or decomposition The temperature is mixed in a short period of time, and the component-based cross-linking agent and the like are liable to cause reaction or decomposition under heat.

＜ Rubber crosslinked products ＞

The rubber crosslinked product of the present invention is obtained by crosslinking the acrylic rubber composition of the present invention.

The rubber crosslinked product of the present invention can be produced by using the acrylic rubber composition of the present invention and a molding machine corresponding to a desired shape, such as an extruder, an injection molding machine, a compressor, and a roller. Then, it is shaped, a crosslinking reaction is performed by heating, and the shape is fixed to be a rubber crosslinked product. In this case, crosslinking may be performed after forming in advance, or forming and crosslinking may be performed at the same time. The molding temperature is usually 10 to 200 ° C, preferably 25 to 120 ° C. The crosslinking temperature is usually 130 to 220 ° C, preferably 150 to 190 ° C, and the crosslinking time is usually 2 minutes to 10 hours, and preferably 3 minutes to 5 hours. As the heating method, a method used for the crosslinked rubber such as pressure heating, steam heating, oven heating, and hot air heating may be appropriately selected.

In addition, depending on the shape, size, and the like of the rubber cross-linked product, the rubber cross-linked product of the present invention may be further heated for secondary cross-linking. The secondary cross-linking varies depending on the heating method, cross-linking temperature, shape, etc., but it is preferably carried out for 1 to 48 hours. The heating method and heating temperature may be appropriately selected.

In addition, the rubber crosslinked product of the present invention thus obtained is suitable for use in a wide range of fields such as transportation machinery such as automobiles, general equipment, and electrical equipment, as sealing materials such as O-rings, packaging, oil seals, and bearing seals; Sheets; buffer materials, shock-proof materials; wire covering materials; industrial tapes; pipes and hoses; sheet materials; etc.

Examples are described below.

Examples and comparative examples are given below to explain the present invention more specifically. In addition, the "part" in each case is a weight basis as long as it is not specifically limited.

Various physical properties were evaluated according to the following methods.

[Muni viscosity (ML1 + 4, 100 ℃)]

Measure the Mooney viscosity (Polymer Mooney) of acrylic rubber in accordance with JIS K6300.

[Content of specific lubricant in acrylic rubber]

The acrylic rubber was dissolved in tetrahydrofuran, and tetrahydrofuran was used as a developing solvent, and GPC measurement was performed to measure the content of the specific lubricant in the acrylic rubber. Specifically, from the graph obtained by GPC measurement, the integral 値 corresponding to the peak of the molecular weight of the specific lubricant used in the manufacture is obtained, and these integrals 値 are compared with the integral 値 of the peak of the acrylic rubber. Calculate the weight ratio of the molecular weight corresponding to these integrals, and calculate the content of the specific lubricant.

[Probe tack test]

The acrylic rubber composition was subjected to a probe tack test using a tack tester (TAC-1000: manufactured by RHESCA). Specifically, an acrylic rubber sample formed into a size of 30 mm × 20 mm × 2 mm was pressed under the conditions of a pressing speed of 0.05 mm / s, a pressing load of 20 gf, and a pressing holding time of 10 seconds. . Next, the adhesive strength (N) when the SUS probe was pulled up at a pulling speed of 15 mm / s was measured. The lower the tack strength, it can be judged that the lower the tackiness to the roll and the more excellent the roll processability when the roll is processed.

[Tensile strength, elongation]

The acrylic rubber composition was put into a mold having a length of 15 cm, a width of 15 cm, and a depth of 0.2 cm, and was pressurized at a pressure of 10 MPa and simultaneously at 170 ° C. for 20 minutes, thereby performing primary crosslinking. Next, using a gear oven, the obtained primary crosslinked product was further heated at 170 ° C. for 4 hours to be crosslinked twice to obtain a sheet-like rubber crosslinked product. The obtained rubber cross-linked product was punched with a No. 3 dumbbell to prepare a test piece. Next, using this test piece, the tensile strength and elongation were measured in accordance with JIS K6251.

[Exudation test]

With respect to the acrylic rubber composition, a sheet-like rubber crosslinked product was obtained under the same conditions as described above, and the obtained rubber crosslinked product was left at room temperature for one day, and then visually judged. If there is exudation, white powder or liquid can be recognized on the surface of the rubber crosslinked material.

If there is exudation, there is a possibility that it may become a cause of dirt when used as various materials, or the equipment may be malfunctioned due to the exuded substance. Therefore, if the exudation occurs, the use may be restricted, so it is desirable not to Will ooze. However, it can be used without any problem in applications where incorporation is not important.

[Manufacturing example 1]

In a mixing container equipped with a homogenizer, 46.294 parts of pure water, 49.3 parts of ethyl acrylate, 49.3 parts of n-butyl acrylate, 1.4 parts of fumaric acid mono-n-butyl ester, and 0.567 parts of anion are charged. Surfactant sodium lauryl sulfate (trade name "EMAL 2FG", manufactured by Kao Corporation), 1.4 parts of polyoxyethylene dodecyl ether (trade name "EMULGEN 105") as a nonionic surfactant, weight average molecular weight: About 1500, manufactured by Kao Corporation), and 0.25 parts of polyoxyethylene stearyl ether phosphate (trade name "PHOSPHANOL RL-210"), weight average molecular weight: about 500, manufactured by Toho Chemical Industry Co., Ltd. By stirring, a monomer emulsion was obtained.

Next, 170.853 parts of pure water and 2.97 parts of the monomer emulsion obtained above were put into a polymerization reaction tank equipped with a thermometer and a stirring device, and cooled to a temperature of 12 ° C. under a nitrogen stream. Next, in a polymerization reaction tank, 145.54 parts of the above-obtained monomer emulsion, 0.00033 parts of ferrous sulfate as a reducing agent, 0.264 parts of sodium ascorbate as a reducing agent, and polymerization were continuously dropped over 3 hours. 7.72 parts of a 2.85 wt% potassium persulfate aqueous solution (the amount of potassium persulfate is 0.22 parts) of the starter. Thereafter, the temperature in the polymerization reaction tank was maintained at 23 ° C., and the reaction was continued for 1 hour, and the polymerization conversion rate was confirmed to be 95%. Hydroquinone was added as a polymerization terminator to stop the polymerization reaction to obtain an emulsion polymerization solution. .

Next, based on 100 parts of the emulsified polymerization solution obtained by polymerization, 0.3 part of 3- (3,5-bis-tertiarybutyl-4-hydroxyphenyl) propanoic acid octadecyl ester as an anti-aging agent ( octadecyl 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate) (trade name "Irganox 1076", manufactured by BASF) (compared to the total of the monomers used in the preparation of the emulsion polymerization solution (also That is, 100 parts of ethyl acrylate, n-butyl acrylate, and mono-n-butyl fumarate are 1 part) and 0.011 parts of polyethylene oxide (weight average molecular weight (Mw) = 100,000) (relative to A total of 100 parts of the filled monomers used in the production of the emulsion polymerization solution (0.039 parts) were mixed to obtain a mixed solution. Next, the obtained mixed liquid was transferred to a coagulation tank, and 60 parts of industrial water was added to 100 parts of the mixed liquid. After the temperature was raised to 85 ° C, the mixed liquid was stirred at a temperature of 85 ° C and continuously added as a coagulation. 3.3 parts of sodium sulfate (11 parts with respect to 100 parts of the polymer contained in the mixed solution), thereby filtering the polymer after agglomerating the polymer to obtain water-containing pellets of the acrylic rubber (A1).

Next, 388 parts of industrial water was added to 100 parts of the solid content of the water-containing pellets obtained above, and after stirring at room temperature for 5 minutes in the aggregation tank, the water was discharged from the aggregation tank to wash the water-containing pellets. Further, in this production example, such water washing was repeated four times.

Next, a sulfuric acid aqueous solution (pH = 3) obtained by mixing 388 parts of industrial water and 0.13 parts of concentrated sulfuric acid was added to 100 parts of the solid content of the water-containing pellets that had been washed with water, and the mixture was stirred at room temperature in a coalescence tank. After 5 minutes, the water was drained from the coagulation tank to pickle the water-containing pellets. The pH of the water-containing pellets after pickling (the pH of the water in the water-containing pellets) was measured and found to be pH = 3. Next, 388 parts of pure water was added to 100 parts of the solid content of the water-containing pellets that had been pickled, and after stirring at room temperature for 5 minutes in the aggregation tank, water was discharged from the aggregation tank to purify the water-containing pellets. Water washing, using a hot air dryer (belt conveyor belt dryer), dried the water-containing pellets that had been washed with pure water at 110 ° C for 1 hour, thereby obtaining solid acrylic rubber (A1). At this time, no adhesion of the acrylic rubber to the hot air dryer was observed.

The obtained acrylic rubber (A1) had a Mooney viscosity (ML1 + 4, 100 ° C) of 33, and the composition of the acrylic rubber (A1) was 49.3% by weight of ethyl acrylate units, 49.3% by weight of n-butyl acrylate units, and 1.4 % By weight of n-butyl fumarate units. In addition, for the acrylic rubber (A1), the content of the lubricant in the acrylic rubber (A1) was measured according to the method described above. The results are shown in Table 1.

[Manufacture example 2]

As the lubricant, 0.25 parts of a higher fatty acid (trade name "Moldwiz Int21G", manufactured by Ba Industries, Ltd.) was used in place of 0.25 parts of polyoxyethylene stearyl ether phosphate, and the same procedure was performed as in Production Example 1. A monomer emulsion is obtained. Next, except that the obtained monomer emulsion was used, it was carried out in the same manner as in Production Example 1. Emulsion polymerization and aggregation were performed to obtain water-containing pellets of the acrylic rubber (A2). The agglomerates were carried out in the same manner as in Production Example 1. The solid acrylic acid rubber was obtained by drying four times with water washing, acid washing, pure water washing, and hot air dryer (belt conveyor belt dryer). (A2). Further, at this time, the adhesion of the acrylic rubber to the hot air dryer during the drying by the hot air dryer was not observed.

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A2) was 33, and the composition of the acrylic rubber (A2) was 49.3% by weight of ethyl acrylate units, 49.3% by weight of n-butyl acrylate units, 1.4 % By weight of n-butyl fumarate units. In addition, for the acrylic rubber (A2), the content of the lubricant in the acrylic rubber (A2) was measured according to the method described above. The results are shown in Table 1.

[Manufacture example 3]

A monomer emulsion was obtained in the same manner as in Production Example 1 except that 0.25 part of polyoxyethylene stearyl ether phosphate as a lubricant was not blended.

Next, 170.853 parts of pure water and 2.97 parts of the monomer emulsion obtained above were put into a polymerization reaction tank equipped with a thermometer and a stirring device, and cooled to a temperature of 12 ° C. under a nitrogen stream. Next, in a polymerization reaction tank, 145.29 parts of the monomer emulsion obtained above, 0.00033 parts of ferrous sulfate as a reducing agent, 0.264 parts of sodium ascorbate as a reducing agent were continuously dropped over a period of 3 hours. The 7.72 parts of the starting agent is a 2.85 wt% potassium persulfate aqueous solution (the amount of potassium persulfate is 0.22 parts). Thereafter, the temperature in the polymerization reaction tank was maintained at 23 ° C., and the reaction was continued for 1 hour. The polymerization conversion rate was confirmed to be 95%. Hydroquinone was added as a polymerization terminator to stop the polymerization reaction to obtain an emulsion polymerization solution.

Next, based on 100 parts of the emulsified polymerization solution obtained by polymerization, 0.3 part of 3- (3,5-bis-tertiarybutyl-4-hydroxyphenyl) propanoic acid octadecyl ester as an anti-aging agent ( Trade name "Irganox (R) 1076", manufactured by BASF Co., Ltd. (to the total of the filling monomers used in the production of the emulsion polymerization solution (ie, ethyl acrylate, n-butyl acrylate, fumarate mono-n-butyl ester) (Total) 100 parts is 1 part), 0.011 parts of polyethylene oxide (weight average molecular weight (Mw) = 100,000) (0.039 parts based on 100 parts in total of the loading monomers used in the production of the emulsion polymerization solution), and 0.075 parts of polyoxyethylene stearyl ether phosphate (trade name "PHOSPHANOL RL-210", weight average molecular weight: about 500, manufactured by Toho Chemical Industry Co., Ltd.) as a lubricant (relative to the filler used in the production of an emulsion polymerization solution) A total of 100 parts of the monomers was 0.25 parts), and a mixed solution was obtained. Next, the obtained mixed solution was transferred to a coagulation tank, and 60 parts of industrial water was added to 100 parts of the mixed solution. After the temperature was raised to 85 ° C, the mixed solution was stirred at a temperature of 85 ° C and continuously added as 3.3 parts of sodium sulphate of the coagulant (11 parts with respect to 100 parts of the polymer contained in the mixed solution), whereby the polymer was coagulated to obtain the water-containing pellets of the acrylic rubber (A3).

Next, the water-containing pellets of the obtained acrylic rubber (A3) were carried out in the same manner as in Production Example 1, and water washing, acid washing, pure water washing, and hot air dryer (belt conveyor belt drying) were performed four times. Machine) to obtain solid acrylic rubber (A3). Further, at this time, the adhesion of the acrylic rubber to the hot air dryer during the drying by the hot air dryer was not observed.

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A3) was 33, and the composition of the acrylic rubber (A3) was 49.3% by weight of ethyl acrylate units, 49.3% by weight of n-butyl acrylate units, 1.4 % By weight of n-butyl fumarate units. Then, the content of the lubricant in the acrylic rubber (A3) was measured according to the method described above. The results are shown in Table 1.

[Manufacture example 4]

With respect to 100 parts by weight of the emulsified polymerization solution obtained in the same manner as in Production Example 3, 0.075 parts of a higher fatty acid (trade name "Moldwiz Int21G", manufactured by Ba Industries, Ltd.) was used as a blending agent (relative to manufacturing A total of 100 parts of the filling monomers used in the emulsification of the polymerization solution were 0.25 parts), except that instead of 0.075 parts of polyoxyethylene stearyl ether phosphate, the same procedure as in Production Example 3 was performed, and a mixed solution was prepared and aggregated. This operation was performed to obtain the water-containing pellets of the acrylic rubber (A4).

Next, the water-containing pellets of the obtained acrylic rubber (A4) were carried out in the same manner as in Production Example 1, and water washing, pickling, pure water washing, and hot air dryer (belt conveyor belt drying) were performed four times. Machine) to obtain solid acrylic rubber (A4). Further, at this time, the adhesion of the acrylic rubber to the hot air dryer during the drying by the hot air dryer was not observed.

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A4) was 33, and the composition of the acrylic rubber (A4) was 49.3% by weight of ethyl acrylate units, 49.3% by weight of n-butyl acrylate units, 1.4 % By weight of n-butyl fumarate units. Then, the content of the lubricant in the acrylic rubber (A4) was measured according to the method described above. The results are shown in Table 1.

[Manufacturing example 5]

A monomer emulsion was obtained in the same manner as in Production Example 1 except that the blending amount of the polyoxyethylene stearyl ether phosphate as a lubricant was changed from 0.25 to 0.5. Next, except that the obtained monomer emulsion was used, it was carried out in the same manner as in Production Example 1. Emulsion polymerization and aggregation were performed to obtain water-containing pellets of the acrylic rubber (A5). The pellets were carried out in the same manner as in Production Example 1. The solid acrylic acid rubber was obtained by performing four times of washing with water, pickling, pure water, and hot air dryer (belt conveyor belt dryer). (A5). Further, at this time, the adhesion of the acrylic rubber to the hot air dryer during the drying by the hot air dryer was not observed.

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A5) was 33, and the composition of the acrylic rubber (A5) was 49.3% by weight of ethyl acrylate units, 49.3% by weight of n-butyl acrylate units, 1.4 % By weight of n-butyl fumarate units. For the acrylic rubber (A5), the content of the lubricant in the acrylic rubber (A5) was measured according to the method described above. The results are shown in Table 1.

[Manufacturing example 6]

A monomer emulsion was obtained in the same manner as in Production Example 2 except that the blending amount of the higher fatty acid as a lubricant was changed from 0.25 to 0.5. Next, except that the obtained monomer emulsion was used, it was carried out in the same manner as in Production Example 2. Emulsion polymerization and aggregation were performed to obtain water-containing pellets of the acrylic rubber (A6). The pellets were carried out in the same manner as in Production Example 2. The solid acrylic acid rubber was obtained by performing four times of water washing, acid washing, pure water washing, and hot air dryer (belt conveyor belt dryer). (A6). Further, at this time, the adhesion of the acrylic rubber to the hot air dryer during the drying by the hot air dryer was not observed.

The obtained acrylic rubber (A6) had a Mooney viscosity (ML1 + 4, 100 ° C) of 33, and the composition of the acrylic rubber (A6) was 49.3% by weight of ethyl acrylate units, 49.3% by weight of n-butyl acrylate units, and 1.4 % By weight of n-butyl fumarate units. In addition, for the acrylic rubber (A6), the content of the lubricant in the acrylic rubber (A6) was measured according to the method described above. The results are shown in Table 1.

[Manufacturing Example 7]

The emulsified polymerization solution obtained in the same manner as in Production Example 3 was carried out in the same manner as in Production Example 3 except that polyoxyethylene stearate phosphate was not blended as a slip agent, and a mixture solution was prepared and agglomerated. Water-containing pellets of acrylic rubber (A7) were obtained.

Next, the water-containing pellets of the obtained acrylic rubber (A7) were carried out in the same manner as in Production Example 1, and water washing, acid washing, pure water washing, and hot air dryer (belt conveyor belt drying) were performed four times. Machine) to obtain solid acrylic rubber (A7). In addition, in Production Example 7, the adhesion of the acrylic rubber to the hot-air dryer during the drying by the hot-air dryer was observed, and the operability was poor.

The obtained acrylic rubber (A7) had a Mooney viscosity (ML1 + 4, 100 ° C) of 33, and the composition of the acrylic rubber (A7) was 49.3% by weight of ethyl acrylate units, 49.3% by weight of n-butyl acrylate units, and 1.4 % By weight of n-butyl fumarate units. Then, the content of the lubricant in the acrylic rubber (A7) was measured according to the method described above. The results are shown in Table 1.

[Example 1]

Using a Banbury mixer, to 100 parts of the acrylic rubber (A1) obtained in Production Example 1, 60 parts of FEF carbon black (trade name "SEAST SO", manufactured by TOKAI CARBON), and 2 parts of stearin were added. Acid, and 2 parts of 4, 4'-bis (α, α-dimethylbenzyl) diphenylamine (4, 4'-bis (α, α-dimethylbenzyl) diphenylamine) (trade name "NOCRAC CD", large (Manufactured by Nisshin Chemical Industry Co., Ltd.), and mixed at 50 ° C for 5 minutes. Next, the obtained mixture was transferred to a roller at 50 ° C, and 0.6 part of hexamethylenediamine carbamate (trade name "Diak # 1", manufactured by DuPont elastomers, blended with aliphatic polyvalent) was blended. Amine compound), and 2 parts of 1,3-di-o-tolylguanidine ("NOCCELER DT", manufactured by Onai Shinko Chemical Industry Co., Ltd., cross-linking accelerator) and kneaded to obtain an acrylic rubber composition .

Next, using the obtained acrylic rubber composition, each of the probe viscosity test, the bleeding test, the tensile strength, and the elongation were measured and evaluated according to the methods described above. The results are shown in Table 2.

[Examples 2 to 6, Comparative Example 1]

An acrylic rubber composition was obtained in the same manner as in Example 1 except that the acrylic rubbers (A2) to (A7) obtained in Production Examples 2 to 7 were used instead of the acrylic rubber (A1) obtained in Production Example 1. The measurement and evaluation results are shown in Table 2 in the same manner.

[Comparative Example 2]

It was the same as Comparative Example 1 except that 0.3 parts of polyoxyethylene stearyl ether phosphate (trade name: "PHOSPHANOL (R) 210", weight average molecular weight: about 500, manufactured by Toho Chemical Industry Co., Ltd.) was blended as a lubricant. This was performed to obtain an acrylic rubber composition, and the results of measurement and evaluation are shown in Table 2 in the same manner.

[Comparative Example 3]

An acrylic rubber composition was obtained in the same manner as in Comparative Example 1 except that 0.3 parts of a higher fatty acid (brand name "Moldwiz Int21G", manufactured by Ba Industries, Ltd.) was further blended as a lubricant. The evaluation results are shown in Table 2.

[Table 1] (* 1) The addition amount of the admixture used to prepare the monomer emulsion is expressed as the blending amount with respect to 100 parts of the loading monomer. (* 2) The amount of the blending agent added to the emulsified polymerization solution before aggregation is expressed in terms of the blended amount of 100 parts of the emulsified polymerization solution. (* 3) The addition amount of the coagulant used in the coagulation step is based on 100 parts of the mixed solution obtained by adding an anti-aging agent, polyethylene oxide, and / or a lubricant to the emulsified polymerization solution. We display together.

[Table 2]

As shown in Tables 1 and 2, the acrylic rubbers obtained through Manufacturing Examples 1 to 6 are all specified slip agents (specific slip agents) of the present invention, that is, those containing phosphate esters or higher fatty acids, and containing The acrylic rubber of this lubricant does not have the adhesion of the acrylic rubber to the hot air dryer during the drying step. It is an excellent one when drying, and an acrylic rubber composition obtained by using this acrylic rubber. In the probe viscosity test, the adhesive strength was low and it was excellent in roll workability (Production Examples 1 to 6, and Examples 1 to 6).

On the other hand, the acrylic rubber obtained in Production Example 7 does not contain the lubricant specified in the invention (specific lubricant). During the drying step, the adhesion of the acrylic rubber to the hot air dryer is caused. Poor operability. Furthermore, the acrylic rubber composition obtained by using such an acrylic rubber has high adhesive strength in a probe tack test and is inferior in roll workability. This tendency is compounded even when the acrylic rubber composition is prepared. The same applies to the case of the specified lubricant (specific lubricant) of the present invention (Comparative Examples 1 to 3).

no

no.

Claims (18)

An acrylic rubber containing a slip agent selected from at least one of a phosphate ester, a fatty acid ester, a stearylamine, and a higher fatty acid. The acrylic rubber according to claim 1, which contains at least one selected from the group consisting of a phosphate ester and a higher fatty acid as the lubricant. The acrylic rubber according to claim 1 or 2, which contains polyoxyethylene higher alcohol phosphate as the lubricant. The acrylic rubber according to claim 1 or 2, which contains a fatty acid having 12 to 20 carbons as the lubricant. The acrylic rubber according to claim 1 or 2, wherein the content of the lubricant is 0.1 to 0.4% by weight. The acrylic rubber according to claim 5, wherein the content of the lubricant is 0.2 to 0.3% by weight. The acrylic rubber according to claim 1 or 2, wherein the content of the acrylic rubber component is 95% by weight or more. The acrylic rubber according to claim 1 or 2, wherein the acrylic rubber is an acrylic rubber containing a carboxyl group. An acrylic rubber composition comprising the acrylic rubber and a crosslinking agent according to claim 1 or 2. A rubber crosslinked product obtained by crosslinking the acrylic rubber composition according to claim 9. A method for manufacturing an acrylic rubber, which is a method for manufacturing the acrylic rubber according to claim 1 or 2, and has the following steps: an emulsification polymerization step, in which the monomers used to form the acrylic rubber are subjected to emulsion polymerization, whereby Obtaining an emulsion polymerization solution; adding a lubricant agent to the emulsion polymerization solution before coagulation, adding the lubricant; and a coagulation step, adding a coagulant to the emulsion polymerization solution and coagulating it, thereby obtaining Watery pellets. A method for manufacturing an acrylic rubber, which is a method for manufacturing the acrylic rubber according to claim 1 or 2, and has the following steps: an emulsion preparation step, which uses monomers, emulsifiers, and water for forming the acrylic rubber Mixing to obtain a monomer emulsion; the lubricant adding step is to add the lubricant to the monomer emulsion prepared in the emulsion preparing step; and the emulsification polymerization step is to add the lubricant to the lubricant adding step. The monomers contained in the monomer-emulsified emulsion are emulsified and polymerized to obtain an emulsified polymerized solution; and a coagulation step is performed by adding an agglomerating agent to the emulsified polymerized solution and agglomerated it to obtain water-containing pellets. . The method for manufacturing an acrylic rubber according to claim 11, wherein in the lubricant addition step, the lubricant is added in an amount of 0.1 to 0.4 weight based on 100 parts by weight of the acrylic rubber component contained in the emulsified polymerization solution. Serving. The method for producing an acrylic rubber according to claim 13, wherein in the lubricant addition step, the lubricant is added in an amount of 0.2 to 0.3 weight based on 100 parts by weight of the acrylic rubber component contained in the emulsified polymerization solution. Serving. The method for producing an acrylic rubber according to claim 10, wherein in the emulsification polymerization step, the monomer is subjected to emulsion polymerization in the presence of a nonionic emulsifier and an anionic emulsifier. The method for producing an acrylic rubber according to claim 15, wherein the amount of the nonionic emulsifier and the anionic emulsifier is 50/50 to 75 / based on the weight ratio of the nonionic emulsifier / anionic emulsifier. 25. The method for producing an acrylic rubber according to claim 11, wherein in the emulsification polymerization step, a monomer, a polymerization initiator and a reducing agent for forming the acrylic rubber are used from the start of the polymerization reaction to an arbitrary time, It was continuously dripped into the polymerization reaction system, and the emulsification polymerization reaction was performed simultaneously. The method for producing an acrylic rubber according to claim 17, wherein the monomer emulsion used to form the acrylic rubber is mixed with an emulsifier and water as a monomer emulsion from the start of the polymerization reaction to an arbitrary time. State, it is continuously dripped to the polymerization reaction system, and at the same time, the emulsion polymerization reaction is performed.