JPH0331302A - Emulsifying agent for polymerization and production of polymer emulsion - Google Patents

Abstract

PURPOSE:To obtain the title emulsifying agent for a radical polymerizable unsaturated monomer, consisting of copolymer (salt) containing an aromatic vinyl hydrocarbon and aromatic vinyl hydrocarbon sulfonic acid (salt) as essential component units and capable of providing a polymer emulsion having excellent stability in emulsion polymerization. CONSTITUTION:The aimed emulsifying agent consisting of (A) an aromatic vinyl hydrocarbon (e.g. styrene), (B) aromatic vinyl hydrocarbon sulfonic acid (salt) and as necessary (C) copolymer (salt) of monomers selected from a group of unsaturated carboxylic acid (salt) or acid anhydride thereof (e.g. maleic anhydride), unsaturated carboxylic acid ester, nitrile group-containing vinyl monomer, nitrogen-containing unsaturated monomer, halogen-containing unsaturated monomer, hydroxyl group-containing unsaturated monomer, sulfonic acid (salt)-containing aliphatic vinyl monomer, olefins and vinyl fatty acid. Furthermore, molar ratio of the component A to the component B is preferably 0.01-0.99:0.9-0.1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an emulsifier for polymerization and a method for producing a polymer emulsion.

[Prior Art] Conventionally, as a method for producing a polymer emulsion, radically polymerizable monomers are polymerized in an aqueous medium in the presence of a water-soluble copolymer obtained from styrene sulfonic acid, methacrylic acid, and methacrylamide. A method is known in which a monomer is polymerized in an aqueous medium at pH 4 or less in the presence of a water-soluble copolymer of methacrylic acid and sodium p-styrene sulfonate (for example, JP-A-58-1277).
No. 04 and Japanese Patent Publication No. 51-31200).

[Problems to be Solved by the Invention] However, these techniques have the problem that the water resistance and adhesiveness of the film obtained from the polymer emulsilone are insufficient.

[Means for Solving the Problems] The present inventors have arrived at the present invention as a result of intensive studies to solve the problems of insufficient water resistance and adhesiveness.

That is, the present invention provides a method for emulsion polymerization of a radically polymerizable unsaturated monomer consisting of a copolymer (salt) (A) having an aromatic vinyl hydrocarbon and an aromatic vinyl hydrocarbon sulfonic acid (salt) as essential constituent units. A method for producing a polymer emulsion, which comprises emulsion polymerizing an emulsifier and a radically polymerizable unsaturated monomer in the presence of the emulsifier according to any one of claims 1 to 5.

Copolymer (salt) containing aromatic vinyl hydrocarbon and aromatic vinyl hydrocarbon sulfonic acid (salt) as essential constituent units (A
) is a water-dispersible or water-soluble copolymer (salt) that has an aromatic vinyl hydrocarbon as an essential constituent unit. Use the description.) Partially sulfonated product (salt) of (a) (
a+), and (1) aromatic vinyl hydrocarbon, (2) aromatic vinyl hydrocarbon sulfonic acid (salt), and optionally (3) unsaturated carboxylic acid (salt) or its acid anhydride, unsaturated carboxylic acid Ester 1 nitrile group-containing vinyl monomer, nitrogen-containing unsaturated monomer, halogen-containing unsaturated monomer,
Examples include copolymers (salts) (b) of monomers selected from the group consisting of hydroxyl group-containing unsaturated monomers, sulfonic acid (salt) group-containing aliphatic vinyl monomers, and olefins.

Preferably, the structural unit is an aromatic vinyl hydrocarbon (
It is a salt of a partially sulfonated co)polymer.

Examples of the copolymer (salt) (A) include the following.

(I) Part of (co)polymer (a) containing aromatic vinyl hydrocarbon as an essential constituent unit, sulfonated product (salt) (a,):
Examples of polymers having aromatic vinyl hydrocarbons as constituent units include polymers of aromatic vinyl hydrocarbons and copolymers of aromatic vinyl hydrocarbons and polymers copolymerized therewith.

Examples of aromatic vinyl hydrocarbons include styrenes such as styrene, α-methylstyrene, and vinyltoluene, and vinylnaphthalene.

Examples of polymers copolymerized with aromatic vinyl hydrocarbons include unsaturated carboxylic acid esters [(meth)acrylic acid alkyl esters, such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate,
(meth)acrylic acid-2-ethylhexyl, (meth)
stearyl acrylate, etc.], fatty acid vinyl [vinyl acetate, etc.], unsaturated carboxylic acid (salt) or its acid anhydride [(meth)acrylic acid, maleic acid (salt) or maleic anhydride, itaconic anhydride (salt) or itaconic anhydride, etc.], olefins [α-olefin, isoprene, inbutylene, diisobutylene, butadiene, chloroprene, etc.], nitrile group-containing vinyl monomers [(meth)acrylonitrile, etc.], nitrogen-containing unsaturated monomers [ Vinyl monomers containing amide groups such as (meth)acrylamide, N-methyl (meth)acrylamide, N-methylol (meth)acrylamide, N,N,-dimethylacrylamide and N-vinylpyrrolidone], halogen-containing polymers [vinyl chloride] , vinylidene chloride, etc., hydroxyl group-containing vinyl monomers [hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate,
triethylene glycol (meth)acrylate, (meth)allyl alcohol, etc.], sulfonic acid (salt) group-containing aliphatic vinyl monomers [■ sulfonic acid group-containing (meth)acrylamide, such as 2-(meth)acrylamide-2
-Methylpropanesulfonic acid, 3-(meth)acrylamidopropane-! -Sulfonic acid 2-(meth)acrylamidoethyl-1-sulfonic acid, 3-[meth)acrylamido-2-hydroxypropanesulfonic acid, P-(
meth)acrylamidomethylbenzenesulfonic acid and salts thereof; sulfonic acid group-containing (meth)acrylates such as 3-(meth)acryloyloxypropane-1-
Sulfonic acid, 4-(meth)acryloyloxybutane-1
-Sulfonic acid, 4-(meth)acryloyloxybutane-
2-sulfonic acid, 2-(meth)acryloyloxyethyl-1-sulfone M, 3-(meth)acryloyloxy-2
-Hydroxypropanesulfonic acid and salts thereof; and (2) aliphatic hydrocarbon vinylsulfonic acid (salts) such as vinylsulfonic acid, (meth)allylsulfonic acid and salts thereof. Among these, unsaturated carboxylic acids (salts) or their anhydrides are preferred, and maleic anhydride is particularly preferred.

In the above, salts include alkali metal salts (sodium, potassium, lithium, etc. salts), alkaline earth metal salts (calcium, magnesium, etc. salts), ammonium salts, namin salts (alkanolamines such as monoethanolamine, gelatin, etc.), Salts of tanolamine, triethanolamine, etc.; alkylamines such as monomethylamine, laurylamine, stearylamine, dimethylamine, trimethylamine, triethylamine, etc.), preferably sodium salts, potassium salts, and ammonium salts. It is.

(Part 2) The aromatic vinyl hydrocarbon content n in the polymer (a) is usually 5 mol% or more, preferably 30 mol% or more.

The molecular weight of the (co)polymer (a) is usually 500-1.00
0,000, preferably 500 to 500,000, more preferably 1.000 to 100,000.

The partially sulfonated product (a) can be produced by a known method using a conventional sulfonating agent without a solvent or in a solvent.

As the solvent, those inert to the sulfonating agent are usually used, such as aliphatic halogenated hydrocarbons having 1 to 2 carbon atoms and nitrated aliphatic hydrocarbons having 1 to 3 carbon atoms. Examples of aliphatic halogenated hydrocarbons include l,2-dichloroethane, methylene dichloride, ethyl chloride, carbon tetrachloride, 1.1
-dichloroethane, 1,1.2.2-tetrachloroethane, chloroform, ethylene dipromide and the like. Examples of two-liter aliphatic hydrocarbons include nitromethane, nitroethane, 1-nitropropane, 2. -Nitropropane, etc. Preferred are aliphatic halogenated hydrocarbons.

The dissolution of (co)polymer (a) depends on the molecular weight of (a), but usually 1 to 100 parts of (a) is dissolved per 100 parts by weight of solvent.
Parts by weight, preferably 5 to 50 parts by weight, are dissolved.

As the sulfonating agent, sulfuric anhydride, chlorosulfuric acid, etc. are used. Preferred is sulfuric anhydride.

Gijo sulfuric anhydride and liquid sulfuric anhydride are inert to inert gases such as nitrogen and dry air, and sulfonating agents such as aliphatic halogenated hydrocarbons having 1 to 2 carbon atoms such as 1,2-dichloroethane and ethyl chloride. Sulfuric anhydride diluted with a suitable solvent can also be used. The concentration of sulfuric anhydride diluted with inert gas is usually 1-15
% by volume, preferably 3-5% by volume. The concentration of sulfuric anhydride diluted with an inert solvent is usually 1 to 50 mLm%, preferably 5 to 20% by weight.

Moreover, a complex of sulfuric anhydride and Lewis base can also be used. Examples of Lewis bases include trialkyl phosphates such as triethyl phosphate and trimethyl phosphate;
Examples include fatty acid alkyl esters such as ethyl acetate and ethyl balmitate, and ethers or thioethers such as dioxane, thioxane and diethyl ether. Preferred Lewis bases are trialkyl phosphates,
and fatty acid alkyl esters.

The amount of the sulfonating agent to be used is usually 0.00 to 1 mole of aromatic vinyl hydrocarbon single unit in (a) in the (co)polymer.
It is 1 to 2 mol m.

The sulfonation reaction is usually carried out at 0 to 80°C, preferably at 1
It is carried out at 0-50°C and in anhydrous conditions.

The sulfonated product is preferably neutralized with a neutralizing agent such as hydroxides and carbonates of alkali metals, alkaline earth metals, etc.; ammonia, amines, etc. to form salts.

The solvent is removed by conventional methods such as branching, filtration, distillation, etc. to obtain a water-dispersible or water-soluble aqueous liquid or powder cane partially sulfonated product (salt).

Patent application 1- in which the present applicant has applied for a patent for a method other than the above-mentioned method
Sulfonation can also be carried out by the methods previously described in Japanese Patent Application No. 81189, Japanese Patent Application No. 1-114593, and Japanese Patent Application No. 1-117832.

(n) (+) aromatic vinyl hydrocarbon, (2) aromatic vinyl hydrocarbon sulfonic acid (salt), and optionally (3
) Unsaturated carboxylic acid (salt) or its acid anhydride, unsaturated carboxylic acid ester, nitrile group-containing vinyl monomer,
From the group consisting of nitrogen-containing unsaturated monomers, halogen-containing unsaturated monomers, hydroxyl group-containing unsaturated monomers, sulfonic acid (salt) group-containing aliphatic vinyl monomers, olefins, and fatty acid vinyl (Co)polymer (salt) of selected monomers
(b): Examples of the aromatic vinyl hydrocarbon include those described in (I) above.

The aromatic vinyl hydrocarbon sulfonic acids (salts) include the above-mentioned aromatic vinyl hydrocarbon sulfonic acids (salts), in detail p.
- and 0-styrenesulfonic acid, styrene disulfonic acid, α-methylstyrenesulfonic acid, vinylphenylmethanesulfonic acid, and salts thereof. Examples of the salt include those described in (I).

Unsaturated carboxylic acids (salts) or their acid anhydrides, unsaturated carboxylic esters, nitrile group-containing vinyl monomers, nitrogen-containing unsaturated monomers, halogen-containing monomers, hydroxyl-based vinyl monomers, sulfones Acid (salt) group-containing aliphatic vinyl monomers, olefins, fatty acid vinyl, etc. are (I)
Examples include those similar to those described in . Among these, nitrogen-containing unsaturated monomers and unsaturated carboxylic acids (salts) are preferred, and (meth)acrylamide and (meth)acrylic acid are particularly preferred.

There are no particular restrictions on the production of the copolymer (salt) (b), but it can usually be produced by a solution polymerization method.

For example, aromatic vinyl hydrocarbons and sulfonic acids (salts)
The group-containing aromatic vinyl hydrocarbon and other monomers as necessary are mixed with water, lower alkyl alcohol (methyl alcohol, ethyl alcohol, isopropyl alcohol, etc.),
Polymerization is usually carried out at 50 to 150°C in a solvent such as cellosolves (methyl cellosolve, ethyl cellosolve, etc.) or a mixed solvent of two or more thereof. Radical polymerization initiators (persulfate, azobisisobutyronitrile,
benzoyl peroxide, dicumyl peroxide, etc.) is usually 0.1~! 5% by weight is used. Chain transfer agents (lauryl mercaptan,
thioglycolic acid, mercaptoethanol, etc.).

The molecular weight of the polymer (salt) (A) in the present invention is usually 5
00-1.000.000, preferably 500-500
．． 0001, more preferably 1,000 to 100,0
It is 00. If the molecular weight is less than 500, the water resistance and adhesion of the film obtained from the polymer emulsilon will be insufficient, and I.

If it exceeds ooo or ooo, the polymerization stability of the polymer emulsilone will deteriorate.

In the copolymer (salt) (A), the molar ratio of aromatic vinyl hydrocarbon to aromatic vinyl hydrocarbon sulfonic acid (salt) or aromatic vinyl hydrocarbon sulfonate (salt) is usually 0.01:0. 99-0.9: 0.1. Preferably it is 0°3:0.7-G, 9:0.1. The molar ratio of aromatic vinyl hydrocarbons is 0.0! If there are no grooves, the water resistance of the polymer emulsion film will be insufficient, and if it exceeds 0.99, the stability of the polymer emulsion will deteriorate.

The content of sulfonic acid groups in the copolymer (salt) (A) is usually 3 to 50% based on the weight of the copolymer excluding the salt component,
Preferably it is 10-40%. When 3% is left undropped, the stability of the polymer emulsilon deteriorates.

A polymer emulsion can be produced by carrying out emulsion polymerization of a polymerizable unsaturated compound using the emulsifier of the present invention. Examples of polymerizable unsaturated compounds to which the emulsifier of the present invention can be applied include monomers for aqueous polymerization. For example, vinyl ester monomers [such as vinyl acetate], acrylic monomers containing carboxyl, ester, nitrile, or amide groups [(meth)
Acrylic acid, methyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (meth)acrylonitrile, (meth)acrylamide, etc.], aromatic hydrocarbon monomers [styrene, divinylbenzene, etc.] , conjugated diolefins [butadiene, isoprene, chloroprennate], halogen-containing hydrocarbon monomers [vinyl chloride, vinylidene chloride, etc.], aliphatic hydrocarbon monomers [such as ethylene, unsaturated polycarboxylic acids or their esters [@hydromalein] Examples include acids, methyl maleate, and the like.

When carrying out emulsion polymerization of a polymerizable unsaturated compound using the emulsifier of the present invention, the amount of the emulsifier used is usually 0.1 to 20% by weight, preferably 0.5 to 10% by weight as an active ingredient, based on the monomer to be polymerized. Heavy view% weight. Polymerizations are usually carried out using m-type initiators and accelerators. As this polymerization initiator and accelerator, known ones may be used.
For example, examples of initiators include hydrogen peroxide, potassium peroxide, ammonium persulfate, sodium peroxide, t-butylhuman peroxide, azobisisobutyronitrile, azobisisovaleronitrile, and the like, and accelerators include , sodium bisulfite, sodium thiosulfate, ferrous ammonium sulfate, copper sulfate, and the like.

The method of carrying out emulsion polymerization using the emulsifier of the present invention is similar to conventional methods. If necessary, other emulsifiers such as anionic surfactants such as alkyl sulfates, alkylaryl sulfonates or fatty acid salts, alkylaryl polyoxyethylene or pluronic type nonionic surfactants may be used in combination. can be done, but
If it is more than 50% by weight of the emulsifier of the present invention, it is preferable because the purpose of the present invention is violated.

The polymerization temperature can be varied depending on the type of monomer to be polymerized, the emulsification state, etc., but it is usually between -5 and -5.
The temperature is 100°C. In addition to water as a commonly used aqueous medium, a organic solvent such as methanol, impropatol, acetone, etc. may be used in combination, and it may be preferable to use a polymerization regulator such as mercaptan.

[Example] The present invention will be further explained below with reference to Examples, but the present invention is not limited thereto. Parts and percentages in the examples are by weight.

Example 1 As a sulfonation reactor, 1,2-dichloroethane 1 was placed in a 3 L four-necked flask equipped with a stirrer and a thermometer.
040 g and triethyl phosphate 18.2 g (Q, 1
mol) was added. In addition, in advance, polystyrene (molecule ff1
20,000) 104g (1.
0 mole)! , was dissolved in 936 g of 2-dichloroethane to obtain solution A.

The temperature in the reactor was maintained at 20 to 25°C, and 8 g (0.1 mol) of liquid sulfuric anhydride was gradually added dropwise. Next, 1040 g of solution A and 80 g (+, o mol) of liquid sulfuric anhydride were simultaneously added dropwise over 3 hours.

The dispersion slurry of sulfonated polystyrene was neutralized with an aqueous sodium hydroxide solution. Further, 1,2-dichloroethane was removed by distillation until the odor of 1,2-dichloroethane in the aqueous solution of the sulfonated product disappeared to obtain an emulsifier of the present invention which is a sodium salt of sulfonated polystyrene at a concentration of 30%. The sulfonic acid content of the polymer was 35% by weight.

Examples 2 to 4 Various polystyrenes were reacted in the same manner as in Example 1 to obtain emulsifiers of the present invention which are sodium salts of sulfonated polystyrenes. The results are shown in Table-1.

Table 1 Example 5 120 g of water and 180 g of isopropyl alcohol were charged into an IL Nikolon equipped with a stirring blade, a cooling tube, a dropping funnel, a nitrogen blowing tube, and a thermometer, and the temperature was raised to reflux temperature under a nitrogen stream. Styrene 20 in the dropping funnel
In another dropping funnel, add 100g of water, 60g of sodium styrene sulfonate, and 2g of acrylamide.
Prepare 0g and add sodium persulfate TG and water to another drip load! Og was prepared, and each was dropped into the Kolben at the same time over a period of about 2 hours. After the dropwise addition, the mixture was aged under reflux for about 2 hours. After aging, the isopropyl alcohol was distilled off and water was added to obtain a 30% concentration liquid of the water-soluble polymer which is the emulsifier of the present invention. The sulfonic acid content of the polymer was 28% by weight.

Comparative Example 1 120 g of water and 180 g of isopropyl alcohol were charged into an IL Nikolon equipped with a stirring blade, a cooling tube, a dropping funnel, a nitrogen blowing tube, and a thermometer, and the temperature was raised to reflux temperature under a nitrogen stream. 100g of water in the dropping funnel
, Prepare 100g of sodium styrene sulfonate,
A separate dropping funnel was charged with 1 g of sodium persulfate and 10 g of water, and each was simultaneously dropped into the Kolben over about 2 hours. After the dropwise addition, the mixture was aged under reflux for about 2 hours. After aging, distill off the isopropyl alcohol and add water for 30 minutes.
% concentration of emulsifier water-soluble polymer was obtained. The sulfonic acid content of the polymer was 43% by weight. The average molecular weight is 10
,000.

Examples 6 to 8 and Comparative Example 2 In a reactor equipped with a stirrer, a dropping funnel, a nitrogen inlet, a thermometer, and a reflux condenser, 270 g of ion-exchanged water was added to the solid content of the emulsifier of the present invention (Examples 1.2.5 and 2). Comparative example 1)7.
9g, 0.36g of sodium hydrogen carbonate and 0.9g of ammonium persulfate, and after purging with nitrogen, stirred for 6 hours.
99g of styrene and 81g of butyl acrylate at 5-70℃
g of the mixed monomers were added dropwise from the dropping funnel over a period of 2 hours to carry out polymerization to obtain a milky-white, good polymer emulsilon with a monomer polymerization conversion of 99.5% or more.

Table 2 shows the test results for emulsion polymerization stability, water resistance, and adhesion of the film made from Emulsilon.

Table 2 - Emulsion polymerization stability Emulsilin was filtered through a 150-mesh wire mesh, the residue was washed with water, and the weight of the coagulated product obtained by drying was expressed as a percentage of the weight of the monomers charged.

・Spread the water-resistant emulsilin film on a glass slide and heat it at 60℃ for 8
O, la+m after drying for 24 hours at 20℃
A thin film was produced. The water resistance of this film was tested according to the water drop test method of JIS K-8828.

・Adhesiveness of the film Water resistance of the film made by the same method as glass/film (reinforced with cotton cloth) at 40°C
80° peel strength was measured at a tensile rate of 100+s/min.

[Effects of the Invention] When emulsion polymerization of a polymerizable unsaturated compound is carried out using the emulsifier of the present invention, a polymer emulsilone having excellent emulsion polymerization stability can be produced. Furthermore, films or coatings made from this emulsilon exhibit excellent water resistance and adhesion.

The polymer emulsion obtained using the emulsifier of the present invention has low foaming and excellent stability. In addition to the above-mentioned effects, the resulting polymer film also has antistatic properties, and is easily removable even if dirt, oil, grime, or other dirt adheres to it. performance.

The polymer emulsion obtained by applying the emulsifier of the present invention can be applied to wood, metal, paper, cloth, concrete, etc. by methods such as adhesion, coating, and impregnation, and can be used as an adhesive or coating agent, and also for fibers, plastics, and paper. It is used as an antistatic agent, dyeing aid, and sizing agent for young children.

Claims (1)

[Scope of Claims] 1. Copolymer (salt) containing aromatic vinyl hydrocarbon and aromatic vinyl hydrocarbon sulfonic acid (salt) as essential constituent units
An emulsifier for emulsion polymerization of a radically polymerizable unsaturated monomer consisting of (A). 2. The emulsifier according to claim 1, wherein (A) is a partially sulfonated product (salt) of a (co)polymer having an aromatic vinyl hydrocarbon as an essential constituent unit. 3. (A) is (1) aromatic vinyl hydrocarbon, (2) aromatic vinyl hydrocarbon sulfonic acid (salt) and optionally (
3) Unsaturated carboxylic acid (salt) or its acid anhydride, unsaturated carboxylic acid ester, nitrile group-containing vinyl monomer, nitrogen-containing unsaturated monomer, halogen-containing unsaturated monomer, hydroxyl group-containing unsaturated monomer The emulsifier according to claim 1, which is a copolymer (salt) of a monomer selected from the group consisting of monomers, aliphatic vinyl monomers containing sulfonic acid (salt) groups, olefins, and vinyl fatty acids. 4. The molar ratio of aromatic vinyl hydrocarbon to aromatic vinyl hydrocarbon sulfonic acid (salt) or aromatic vinyl hydrocarbon sulfonate (salt) is 0.01:0.99 to 0.9:0
．． 4. The emulsifier according to claim 1, wherein the emulsifier is 5. The emulsifier according to any one of claims 1 to 4, wherein (A) has a molecular weight of 500 to 1,000,000. 6. A method for producing a polymer emulsion, comprising emulsion polymerizing a radically polymerizable unsaturated monomer in the presence of the emulsifier according to any one of claims 1 to 5.