JPH06248005A - Emulsifier for emulsion polymerization - Google Patents

Abstract

(57) [Summary] [Structure] An emulsifier for emulsion polymerization represented by the following general formula (I). [Chemical 1] [In the formula, R ¹ is an alkyl group having 6 to 18 carbon atoms, an alkenyl group or an aralkyl group, and R ² is hydrogen or a carbon number 6
~ 18 alkyl group, alkenyl group or aralkyl group, R ³ is hydrogen or 1-propenyl group, A is C 2
~ 4 alkylene group or substituted alkylene group, n is 1 to
An integer of 200, m is 1 or 2, M is hydrogen or an alkali metal, ammonium ion or an alkanolamine residue]. [Effect] By using the above-mentioned emulsifier, the stability at the time of emulsion polymerization becomes good, and the water resistance and adhesiveness of the polymer film obtained from the polymer emulsion can be remarkably improved.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an emulsifier for emulsion polymerization.

[0002]

As an emulsifying agent for emulsion polymerization, anionic surfactants such as sodium dodecylbenzene sulfonate and polyoxyethylene nonylphenyl ether and nonionic surfactants have been conventionally used. However, in the polymer film obtained from the polymer emulsion using these emulsifiers, the emulsifier used remains in the polymer film in a free state. Therefore, there have been problems such as poor water resistance and adhesiveness of the film.

Therefore, many reactive emulsifiers having a copolymerizable unsaturated group have been proposed as measures for solving the above problems.

For example, JP-B-46-12472, JP-A-54-14431, JP-B-46-34894, JP-B-56-29657, and JP-A-51-30285,
JP-B-49-46291 and JP-A-56-12769
No. 7, etc. describes an anionic reactive surfactant,
Further, JP-A-56-28208 and JP-A-50-98.
No. 484 and the like describe nonionic reactive surfactants, and emulsion polymerization of various monomers has been attempted.

Generally, a reactive emulsifier having an acryl group or a methacryl group as a copolymerizable unsaturated group is excellent in copolymerizability with a monomer, but on the contrary, has a problem in stability during emulsion polymerization. There are many aggregates during polymerization,
There were problems that the particles produced were coarse and the stability over time was poor.

The present inventors have already proposed, as an emulsifying agent having an unsaturated group suitable for emulsion polymerization, to JP-A-62-10.
No. 0502, JP-A No. 62-221431, and other reactive emulsifiers having an allyl group as an unsaturated group have been found.

However, the reactive emulsifier having an allyl group is often inferior in the copolymerizability with the monomer, and the polymer film obtained from the polymer emulsion is sufficiently satisfactory in water resistance and adhesiveness. The reality is that they have not been obtained.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to improve the stability during emulsion polymerization and to obtain the polymer emulsion. Another object of the present invention is to provide an improved emulsifier for reactive emulsion polymerization, which can remarkably improve the adhesiveness when the water resistance and adhesive strength of the polymer film are required.

[0009]

[Means for Solving the Problems]

(1) Progress of the invention As a result of further earnest research after that, it has a 1-propenyl group as an unsaturated group having copolymerizability, and the bonding position of the unsaturated group is a hydrophobic group portion of the emulsifier. Has been found to be suitable as an emulsifying agent for emulsion polymerization, and has arrived at the present invention.

(2) Outline of the Invention Based on the above findings, the present invention is based on an emulsifier for emulsion polymerization represented by the following general formula (I) (hereinafter, also referred to as "the emulsifier of the present invention"). is there.

[0011]

[Chemical 4] [In the formula, R ¹ represents an alkyl group, an alkenyl group or an aralkyl group having 6 to 18 carbon atoms. R ² is hydrogen or has 6 carbon atoms
~ 18 alkyl groups, alkenyl groups or aralkyl groups. R ³ is hydrogen or a 1-propenyl group. A has 2 carbon atoms
~ 4 alkylene group or a substituted alkylene group. n is 1
An integer of 200, and when n is 2 or more, (AO)
_n is a homopolymer consisting of one type of repeating unit represented by the following formula (i)

[Chemical 5] Or a different A represented by the following formula (ii)
Block polymer or random polymer composed of two or more kinds of repeating units having (A ¹ , A ² ...)

[Chemical 6] May be m is 1 or 2. M is hydrogen or an alkali metal, ammonium ion or an alkanolamine residue. The main items relating to the structure of the invention will be described below item by item.

(3) Substituent In the compound of the general formula (I), the substituent R ¹ is an alkyl group, an alkenyl group or an aralkyl group having 6 to 18 carbon atoms. Examples of the alkyl group include hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group and the like. .

Examples of the alkenyl group include hexenyl group, heptenyl group, octenyl group, nonenyl group, decenyl group, undecenyl group, dodecenyl group, tridecenyl group, tetradecenyl group, pentadecenyl group, hexadecenyl group, heptadecenyl group, octadecenyl group. Etc. are illustrated.

Further, examples of the aralkyl group include a styryl group, a benzyl group and a cumyl group.

The above alkyl group, alkenyl group and aralkyl group may be mixed in the compound of the formula (I).

Next, the substituent R ² is a hydrogen atom or an alkyl group having 6 to 18 carbon atoms, an alkenyl group or an aralkyl group, and examples of the alkyl group include a hexyl group, a heptyl group, an octyl group and a nonyl group. , Decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group and the like, and may be a mixture thereof.

Examples of the alkenyl group include a hexenyl group, a heptenyl group, an octenyl group, a nonenyl group,
Examples thereof include a decenyl group, an undecenyl group, a dodecenyl group, a tridecenyl group, a tetradecenyl group, a pentadecenyl group, a hexadecenyl group, a heptadecenyl group and an octadecenyl group.

Further, examples of the aralkyl group include a styryl group, a benzyl group, a cumyl group and the like.

The above alkyl group, alkenyl group and aralkyl group may be mixed in the compound of the formula (I).

R ³ is a hydrogen atom or a 1-propenyl group. The 1-propenyl group includes trans and cis stereoisomers. In the present invention, either one of these isomers or a mixture thereof can be used, but the trans isomer is more preferably selected.

The substituent A is an alkylene group having 2 to 4 carbon atoms or a substituted alkylene group. Specifically, the alkylene group is an ethylene group, a propylene group, a butylene group, an isobutylene group or the like, and the substituted alkylene group is a 1,2-butylene oxide group or a propylene oxide group. n is an integer of 1 to 200, and more preferably 2 to 100.

When n is 2 or more, (AO) _n in the formula (I) may be a homopolymer consisting of one kind of repeating unit (see the above formula (i)) or different substituents A It may be a block polymer or a random polymer (see the above formula (ii)) composed of two or more kinds of repeating units having (A1, A2, A3 ...). Alternatively, n is 1
In the case where n is 2 or more and (A
O) _n may be a mixture of two or more compounds selected from homopolymers, block polymers or random polymers.

(4) Synthesis The reaction conditions for obtaining the emulsifier for emulsion polymerization of the present invention are not particularly limited. For example, after adding an alkylene oxide to an alkylated propenylphenol by a conventional method, a hydroxyl group is added. Or by reacting with a monohalogenated acetic acid for carboxylation, or by reacting acrylonitrile or an acrylic ester, saponification with an alkali, and neutralizing with an alkaline substance if necessary. Can be manufactured.

(5) Emulsion Polymerization Monomer Various monomers can be used as the monomer applicable to the emulsion polymerization using the emulsifier of the present invention. For example, acrylic acid, methyl acrylate, butyl acrylate, acrylic acid 2 -Acrylic monomers such as ethylhexyl, methyl methacrylate, acrylonitrile, acrylamide, acrylic acid hydroxyethyl ester, for example, aromatic monomers such as styrene and divinylbenzene, vinyl ester monomers such as vinyl acetate, vinyl chloride, vinyldene chloride, etc. In addition to the halogenated olefinic monomers, conjugated diolefinic monomers such as butadiene, isoprene, and chloroprene, and the like, ethylene, maleic anhydride, methyl maleate, and the like.

The emulsifier of the present invention can be used for emulsion polymerization or suspension polymerization of one or more of the above monomers.

(6) Polymerization conditions The polymerization initiator used in the emulsion polymerization reaction using the emulsifier of the present invention may be a conventionally known one, for example, hydrogen peroxide,
Potassium persulfate, azobisisobutyl nitrile, benzoyl peroxide, etc. are used.

As the polymerization accelerator, sodium hydrogen sulfite, ferrous ammonium sulfate, etc. are used.

The amount of the emulsifier of the present invention to be used is usually 0.1 to 20% by weight, more preferably 0.
2 to 5.0% by weight is suitable. If desired, other emulsifiers or protective colloid agents may be used in combination.

[0029]

The emulsifier for emulsion polymerization of the present invention has a 1-propenyl group (-CH = CH-CH ₃ ) at the hydrophobic group portion of the molecule.
Therefore, it has excellent copolymerizability with a polymerizable monomer, particularly a vinyl-based monomer, and is easily incorporated into a polymer component. Further, the copolymerization rate is slightly slower than that of an acrylic group, which appears as a good action in the case of emulsion polymerization, and the copolymerization is carried out in the latter stage of particle growth, and there are many types of the copolymerized particles on the surface of the particle. Good stability during polymerization. Therefore, the amount of the emulsifier existing in a free state in the polymer film obtained from the polymer emulsion is remarkably reduced, and the film exhibits extremely excellent water resistance and adhesiveness. In addition, the foaming of the polymer emulsion, mechanical stability, etc. are remarkably improved.

The polymer emulsion obtained by adding the emulsifier of the present invention can be applied to wood, metal, paper, cloth, concrete and the like as an adhesive, a coating agent, an impregnating reinforcing agent and the like.

[0031]

The embodiments and effects of the present invention will be described below with reference to Examples and Comparative Examples, but the examples are merely for the purpose of illustration and are not intended to limit or limit the inventive idea. In the text, "%" and "parts" mean weight basis.

Production Example 1 260 g of nonylpropenylphenol was added to an autoclave.
(1 mol) was charged, and 440 g (10 mol) of ethylene oxide was added under the conditions of a pressure of 1.5 kg / cm ² and a temperature of 130 ° C. using potassium hydroxide as a catalyst to obtain a nonylpropenylphenol ethylene oxide 10 mol adduct. (Hereinafter, "ethylene oxide" is also simply referred to as "EO").

Next, 350 g (0.5 mol) of 10 mol adduct of nonylpropenylphenol EO, which is the above-mentioned reaction composition, is charged into a reaction vessel equipped with a stirrer and a thermometer.
Then with stirring, monochloro sodium acetate 64.1.
g (0.55 mol) is charged at room temperature over 30 minutes. Then, 22 g (0.55 mol) of sodium hydroxide is added to the reaction vessel heated to 40 ° C. over 3 hours. Then, it is made to react at 40 degreeC for 17 hours.

Next, add 500 ml of 10% sulfuric acid, and add 75
The temperature is raised to ℃, after stirring, the mixture is allowed to stand and the aqueous layer is removed.

Next, 400 ml of methylene chloride and 200 ml of water are added to the oil layer and washed with water. After washing with water three times, methylene chloride in the oil layer was removed by distillation.

The reaction composition in which the oil layer remained was neutralized to pH 8.0 with 48% sodium hydroxide and the emulsifier [A] of the present invention was added.
Was obtained (see [Chemical Formula 7] below).

Further, nonylpropenylphenol EO3
The 0 mol adduct was subjected to the same procedure to convert the terminal hydroxyl group to a carboxyl group, and the resulting composition was designated as the emulsifier [B] of the present invention (see [Chemical Formula 7] below).

[0038]

[Chemical 7]

Production Example 2 Distyrylpropenylphenol 34 was placed in an autoclave.
Charge 2 g (1 mol), add 580 g (10 mol) of propylene oxide and then 1320 g (30 mol) of ethylene oxide under the conditions of pressure 1.5 kg / cm ² and temperature 130 ° C. using potassium hydroxide as a catalyst. Then, the obtained distyrylpropenylphenol propylene oxide 10 mol and ethylene oxide 30 mol adduct were obtained. 224.2 g (0.1 mol) of this adduct
Is charged to a reaction vessel equipped with stirrer and thermometer. Next, while agitating, acrylonitrile 5.3 (0.1 mol) was added at 50 ° C. for 1 hour, then the temperature was raised to 80 ° C., and cyanoethylation reaction was carried out for 1 hour.

Next, 200 ml of 10% hydrochloric acid and 200 m of water
1 was added, the temperature was raised to 90 ° C., and the mixture was stirred for 3 hours to saponify the cyano group.

Then, after dehydration under reduced pressure, 200 m of acetone
After adding 1 and filtering, acetone in the filtrate was distilled off to obtain the emulsifier [C] of the present invention (see [Chemical Formula 8] below).

[0042]

[Chemical 8]

Production Example 3 Each emulsifier was produced according to Production Example 1 and Production Example 2 to obtain the emulsifiers [D] to [H] of the present invention (see [Chemical Formula 9] below).

[0044]

[Chemical 9]

Use Example 1 A reactor equipped with a stirrer, a reflux condenser, a thermometer and a dropping funnel was charged with 294 g of ion-exchanged water and 6 g of the emulsifier of the present invention shown in Table 2 and heated to 80 ° C.

After removing the dissolved oxygen in the water with nitrogen gas, 20 g of ethyl acrylate and ammonium persulfate of 0.
5 g was added and pre-polymerized, and 10 minutes after the start of polymerization, 3
180 g of ethyl acrylate was dropped over a period of time and polymerized to obtain an emulsion.

The results of the emulsion polymerization stability, the mechanical stability of the emulsion, the foamability and the water resistance of the polymer film produced from this emulsion are shown in Table 1 below.

For comparison, the same test was carried out for the conventional emulsifiers shown in [Table 1].

[0049]

[Table 1]

Use Example 2 100 g of butyl acrylate, 100 g of styrene, 290 g of ion-exchanged water, 0.5 g of potassium persulfate and 10 g of the emulsifier of the present invention shown in Table 3 were mixed to prepare a mixed monomer emulsion, which was then added with nitrogen gas. Dissolved oxygen was removed.

Next, 100 g of the emulsion of the above mixed monomer was charged into a reactor equipped with a stirrer, a reflux condenser, a thermometer and a dropping funnel, and the temperature was raised to 80 ° C. for polymerization.

Then, the remaining mixed monomer emulsion 40
0.5 g was added dropwise over 3 hours for polymerization to obtain an emulsion.

The results of the emulsion polymerization stability, the mechanical stability of the emulsion, the foamability, and the water resistance and contact angle of the polymer film produced from the emulsion are shown in Table 2 below.

For comparison, the same test was carried out for the conventional emulsifiers shown in [Table 2].

[0055]

[Table 2]

Use Example 3 A reactor equipped with a stirrer, a reflux condenser, a thermometer and a dropping funnel was charged with 250 g of ion-exchanged water and 5 g of the emulsifier of the present invention shown in Table 4 and heated to 80 ° C. After removing dissolved oxygen in water with nitrogen gas, butyl acrylate 1
20 g of 250 g of a mixed monomer obtained by mixing 25 g and 125 g of methyl methacrylate and 0.5 g of ammonium persulfate were added to carry out a prepolymerization, and 10 minutes after the initiation of the polymerization, the remaining mixing was carried out for 3 hours. 230 g of the monomer was added dropwise and polymerized to obtain an emulsion.

For comparison, emulsions were prepared in the same manner for the other reactive emulsifiers shown in [Table 3].

Regarding the emulsion polymerization stability at this time and the obtained emulsion, the amount of unpolymerized emulsifier was determined, and the contact angle and the adhesive force of the polymer film prepared from the emulsion were measured. The results are shown in [Table 3].

[0059]

[Table 3]

[0060]

As described above, according to the present invention, the stability during emulsion polymerization can be improved, and the water resistance and the adhesive strength of the polymer film obtained from the polymer emulsion are required. It is possible to provide an improved emulsifier for reactive emulsion polymerization capable of significantly improving its adhesiveness, which contributes to the development of related industries and the interests of consumers.

Claims (1)

[Claims] 1. An emulsifying agent for emulsion polymerization represented by the following general formula (I). [Chemical 1] [In the formula, R ¹ represents an alkyl group, an alkenyl group or an aralkyl group having 6 to 18 carbon atoms. R ² is hydrogen or has 6 carbon atoms
~ 18 alkyl groups, alkenyl groups or aralkyl groups. R ³ is hydrogen or a 1-propenyl group. A has 2 carbon atoms
~ 4 alkylene group or a substituted alkylene group. n is 1
An integer of 200, and when n is 2 or more, (AO)
_n is a homopolymer represented by the following formula (i) and consisting of one kind of repeating unit: Or a different A represented by the following formula (ii)
A block polymer or a random polymer composed of two or more kinds of repeating units having (A ¹ , A ² ...) May be m is 1 or 2. M is hydrogen or an alkali metal, ammonium ion or an alkanolamine residue. ]