JPH10273502A - Production of nonaqueous polymer dispersion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To economically and easily produce a nonaqueous polymer dispersion by adding a nonaqueous dispersion medium to an aqueous polymer dispersion and then removing the water in the dispersion medium to below a specified amount. SOLUTION: A styrene monomer and a conjugated diene monomer comprising, e.g. 1,3-butadiene are mixed together with a dispersant comprising, e.g. sodium lauryl sulfate to a solvent comprising mainly water to form a dispersion, and a polymerization initiator comprising, e.g. ammonium persulfate is added in an amount of 0.01-10 pts.wt. based on 100 pts.wt. total monomers to the dispersion to effect thermal polymerization, thus giving a rubber latex comprising, e.g. a styrene/butadiene copolymer having a particle diameter of 0.01-1.00 μm. A nonaqueous dispersion medium comprising, e.g. N-methylpyrrolidone and having a boiling point of 85-350 deg.C is added to an aqueous emulsion comprising the rubber latex having unreacted material removed therefrom by, e.g. steam distillation, and water is then removed by evaporation to give a water content of 5 wt.% or less, thus giving a nonaqueous polymer dispersion in which rubber particles have a gel content of at most 30 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a non-aqueous polymer dispersion, and more particularly to a method for producing a non-aqueous polymer dispersion which is used for the same purpose as the water-based polymer dispersion, and particularly suitable for water-resistant applications. .

[0002]

2. Description of the Related Art Aqueous polymer dispersion (hereinafter,
The term "latex" is a substance in which polymer fine powder is uniformly dispersed in water in particles, and is usually called latex ("Emulsion Latex Handbook", page 15, published by Taisei Co., Showa). Issued in 1957). On the other hand, a substance in which a polymer fine powder is uniformly dispersed in a non-aqueous liquid is usually distinguished from the above-mentioned latex, and is referred to as a non-aqueous polymer dispersion in the present invention. Latex or non-aqueous polymer dispersion has a wide range of applications such as paints, adhesives, pressure-sensitive adhesives, sealing materials, etc. Generally, non-aqueous polymer dispersions are difficult to manufacture, so special applications unsuitable when water is present, For example, it is used to some extent in applications where water is required, applications that require quick drying, and the like.

Conventionally, as a method for producing a non-aqueous polymer dispersion, a polymer powder is mixed with a dispersion stabilizer into a non-aqueous dispersion medium, if necessary, and mechanically produced by a ball mill, a sand mill, a pigment disperser or the like. The most common method is to disperse them. In addition, a dispersion polymerization method of producing a non-aqueous polymer dispersion by polymerizing the raw material monomer by using a non-aqueous dispersion medium in which the raw material monomer is dissolved but the generated polymer is not dissolved (for example, JP-A-56-145911). Gazette, JP-A-4-23
No. 805, JP-A-4-261404, JP-A-6-41402, JP-A-7-206933, etc.) or a polymer is dissolved in an organic solvent.
A method of producing an organic polymer dispersion by adding an immiscible organic dispersion medium to the organic solvent and then removing the organic solvent (for example, JP-A-61-47705) is known. ing.

In a general method of mechanically dispersing a mixture of a polymer fine powder and a dispersion medium using a disperser, it is necessary to pulverize the polymer in advance to such an extent that the polymer is sufficiently dispersed in the dispersion medium. In addition, it is necessary to uniformly monodisperse the finely divided polymer in the dispersion medium without agglomerating it. However, some polymers are very difficult to pulverize, and even if they can be finely pulverized immediately after pulverization, or when mixed with a dispersion medium, they agglomerate or adhere to each other to produce a non-aqueous polymer dispersion. Many polymers cannot be made. In particular, polymers having rubber-like elasticity (hereinafter sometimes simply referred to as rubber) have a strong tackiness and adhere to each other immediately after being mechanically powdered, so that it is very difficult to obtain fine rubber powder. It is difficult, and even if a fine powder of rubber is obtained, it is more difficult to uniformly disperse it in a dispersion medium.

On the other hand, a dispersion polymerization method and JP-A-61-4770 are disclosed.
The method disclosed in Japanese Patent Publication No. 5 is an effective production method because there is no need to pulverize the polymer as described above, and a fine non-aqueous polymer dispersion having a very uniform and fine particle diameter can be obtained. . However, such known non-aqueous polymer dispersions are known only for special resins such as polymers, and not for rubber. In addition, since its manufacturing method is complicated, it is only used for very limited special applications such as column packing materials, various spacers, and diagnostic agent carriers.

[0006]

Under the above-mentioned conventional techniques, the present inventors have conducted extensive studies to obtain a non-aqueous polymer dispersion, and as a result, by replacing the water of the latex with the non-aqueous dispersion medium, The present inventors have found that an aqueous polymer dispersion can be easily manufactured at low cost, and have completed the present invention.

[0007]

Thus, according to the present invention, a non-aqueous dispersion medium is added to a water-based polymer dispersion, and then the water content in the dispersion medium is removed to 5% by weight or less. A method for producing a polymer dispersion is provided.

[0008] 1. Water-Based Polymer Dispersion In the present invention, the water-based polymer dispersion as a raw material may be a latex in which polymer particles are dispersed in a liquid mainly containing water. For example, the latex may be any of rubber latex, resin latex, a mixed latex of rubber and resin, and may be any of natural latex, synthetic latex, and artificial latex. Latex generally has a large variety of types and their classifications are diverse, but it is a substance in which a polymer is dispersed in a dispersion medium mainly containing water, such as various commercially available latex and latex produced for a special purpose. Anything will do as long as it is available.

Further, an aqueous polymer dispersion (so-called emulsion) obtained during a process of producing a polymer block produced by an emulsion polymerization method or a suspension polymerization method.
Naturally obtained latex such as sap such as latex of natural rubber, or dispersion in which fibrous polymer is entangled and dispersed in water is also included as one kind of the latex of the present invention. When the polymer in the latex is a latex having rubber-like elasticity (hereinafter sometimes simply referred to as rubber latex), a non-aqueous rubber dispersion, which has been very difficult to manufacture in the past, can be manufactured inexpensively and easily. Very effective for.

Here, the polymer having rubber-like elasticity means the glass transition temperature (hereinafter, referred to as Tg) of at least one of the polymer itself and at least one of the monomers constituting the polymer. Is a polymer having a temperature of 30 ° C. or lower. The rubber latex used in the present invention can be obtained by a conventional polymerization method, for example, a two-stage polymerization method such as an emulsion polymerization method, a suspension polymerization method, or a seed polymerization method. The dispersants used in these polymerization methods may be those used in the synthesis of ordinary latex, and specific examples thereof include benzenesulfonates such as sodium dodecylbenzenesulfonate and sodium dodecylphenylethersulfonate; lauryl sulfate Alkyl sulfates such as sodium and sodium tetradodecyl sulfate; sulfosuccinates such as sodium dioctyl sulfosuccinate and sodium dihexyl sulfosuccinate; fatty acid salts such as sodium laurate; sodium polyoxyethylene lauryl ether sulfate; polyoxyethylene nonyl phenyle -Ethoxysulfate salts such as tersulfate sodium salt; alkane sulfonates; alkyl ether phosphate sodium salt; polyoxyethylene nonylphene Ether, polyoxyethylene sorbitan lauryl ester, polyoxyethylene -
Nonionic emulsifier such as polyoxypropylene block copolymer; water-soluble gelatin, maleic anhydride-styrene copolymer, polyvinylpyrrolidone, sodium polyacrylate, polyvinyl alcohol having a degree of polymerization of 700 or more and a saponification degree of 75% or more. Examples include volatile polymers,
These may be used alone or in combination of two or more.
The addition amount of the dispersant can be set arbitrarily, and the total amount of the monomer is 100
It is usually about 0.01 to 10 parts by weight with respect to parts by weight, but a dispersant may not be used depending on the polymerization conditions.

The polymerization initiator may be one used in usual emulsion polymerization, suspension polymerization, seed polymerization and the like.
Persulfates such as potassium persulfate and ammonium persulfate;
Hydrogen peroxide: Organic peroxides such as benzoyl peroxide and cumene hydroperoxide are available. These can be used alone or in combination with reducing agents such as acidic sodium sulfite, sodium thiosulfate and ascorbic acid to initiate redox polymerization. Can also be polymerized by
2'-azobisisobutyronitrile, 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2 '-Azobisisobutyrate,
Azo compounds such as 4,4′-azobis (4-cyanopentanoic acid); 2,2′-azobis (2-aminodipropane) dihydrochloride, 2,2′-azobis (N, N′-dimethylene) Isobutylamidine), 2,
It is also possible to use an amidine compound such as 2′-azobis (N, N′-dimethyleneisobutylamidine) dihydrochloride. These can be used alone or in combination of two or more. The amount of the polymerization initiator used is 0.01 to 100 parts by weight based on the total weight of the monomers.
It is 10 parts by weight, preferably 0.1 to 5 parts by weight. The polymerization temperature and the polymerization time can be arbitrarily selected depending on the polymerization method and the type of the polymerization initiator used, but usually about 50 to 20.
The temperature is 0 ° C., and the polymerization time is about 0.5 to 20 hours.
Further, at the time of polymerization, a generally known additive, for example, a polymerization aid such as an amine can be used in combination.

The shape of the rubber particles in the rubber latex used in the present invention may be spherical, irregular or irregular, and is not particularly limited. 0.005-1000 μm, preferably 0.0
It is 1 to 100 μm, particularly preferably 0.05 to 30 μm.

The monomer constituting the rubber which is the raw material of the rubber particles contained in the rubber latex used in the present invention includes a conjugated diene monomer, a (meth) acrylic acid ester monomer and a monomer copolymerizable therewith. No.

Specific examples of the conjugated diene-based monomer include
1,3-butadiene, isoprene, 2,3-dimethyl-
Examples thereof include 1,3-butadiene, 1,3-pentadiene, and piperylene, and preferably include 1,3-butadiene, isoprene, and 2,3-dimethyl-1,3-butadiene.

Specific examples of the (meth) acrylic acid ester type monomer include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-amyl acrylate, and acrylic. Isoamyl acid, n-acrylic acid
Acrylic esters such as hexyl, 2-ethylhexyl acrylate, hydroxypropyl acrylate, lauryl acrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, methacrylic acid Methacrylates such as n-amyl, isoamyl methacrylate, n-hexyl methacrylate, methacryl-2-ethylhexyl, hydroxypropyl methacrylate, lauryl methacrylate; methyl crotonate, ethyl crotonate, propyl crotonate, butyl crotonate, croton Acid isobutyl, crotonic acid n-
Crotonic acid esters such as amyl, isoamyl crotonic acid, n-hexyl crotonic acid, croton 2-ethylhexyl, and hydroxypropyl crotonic acid; Of these, alkyl (meth) acrylate is preferred, and the alkyl moiety has 1 to 6, preferably 1 to 4 carbon atoms.

Specific examples of monomers which can be copolymerized with conjugated diene monomers or (meth) acrylate monomers include styrene, α-methylstyrene, β-methylstyrene, pt-butylstyrene, chlorostyrene. Styrene-based monomers such as acrylonitrile and methacrylonitrile; acrylamide-based monomers such as acrylamide, N-methylolacrylamide and N-butoxymethylacrylamide; methacrylamide, N-methylolmethacrylamide and N-butoxymethylmethacrylamide Methacrylamide-based monomers such as glycidyl acrylate, glycidyl methacrylate, and allyl glycidyl ether; glycidyl group-containing monomers such as sodium styrenesulfonate and acrylamide Sulfonic acid group-containing monomers such as mail propane sulfonic acid; amino group-containing methacrylic acid monomers such as dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate; methacrylic acid-based monomers such as methoxypolyethylene glycol monomethacrylate; acrylic acid; Unsaturated monocarboxylic acid monomers such as methacrylic acid; maleic acid,
Fumaric acid, citraconic acid, metaconic acid, glutaconic acid,
Unsaturated dicarboxylic acid type monomers such as itaconic acid, tetrahydrophthalic acid, crotonic acid, isocrotonic acid, nadic acid; monooctyl maleate, monobutyl maleate, monooctyl itaconic acid, etc .; and the like. Among these, preferable examples include styrene-based monomers, nitrile group-containing monomers, polycarboxylic acid monomers, unsaturated monocarboxylic acid-based monomers, and alkoxy group-containing methacrylic acid-based monomers.

Examples of the polymer which becomes the rubber particles of the rubber latex prized in the present invention include polybutadiene,
Polyisoprene, styrene-1,3-butadiene copolymer, styrene-isoprene copolymer, styrene-1,3
-Butadiene-isoprene copolymer, 1,3-butadiene-acrylonitrile copolymer, 1,3-butadiene-
Isoprene-acrylonitrile copolymer, styrene-acrylonitrile-1,3-butadiene copolymer, styrene-acrylonitrile-1,3-butadiene-methyl methacrylate copolymer, styrene-acrylonitrile-
1,3-butadiene-itaconic acid copolymer, styrene-
Acrylonitrile-1,3-butadiene-methyl methacrylate-fumaric acid copolymer, polystyrene-polybutadiene block copolymer, styrene-1,3-butadiene-itaconic acid-methyl methacrylate-acrylonitrile copolymer, styrene-acrylic acid n-butyl-itaconic acid-methyl methacrylate-acrylonitrile copolymer,
A homopolymer or copolymer of a conjugated diene-based monomer or a (meth) acrylic acid ester-based monomer such as 2-ethylhexyl acrylate-methyl acrylate-acrylic acid-methoxy polyethylene glycol monomethacrylate, or a conjugated diene-based monomer or ( A preferable example is a copolymer using a (meth) acrylic acid ester-based monomer and various copolymerizable monomers.

Also, ethylene-propylene copolymer, ethylene-propylene-diene copolymer, styrene-butadiene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, styrene-isoprene block Thermoplastic elastomers such as copolymers, styrene-ethylene-propylene-styrene block copolymers, methyl methacrylate polymers, vinyl alcohol polymers and vinyl acetate polymers can also be used as preferred rubbers.

Further, these rubbers are preferably crosslinked using a crosslinking agent. When a cross-linking agent is used, the amount used varies depending on the reaction conditions and the type of rubber,
Usually, it is 30% by weight or less based on rubber.

Specific examples of the crosslinking agent include benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, di-tert-butyl peroxide,
2,5-Dimethyl-2,5-di (peroxide benzoate) hexyne-3,1,4-bis (tert-butylperoxyisopropyl) benzene, lauroyl peroxide, tert-butyl peracetate, 2,5-dimethyl-2, 5-di (tert-butylperoxy) hexyne-3,2,5-trimethyl-2,5-di (ter
t-butylperoxy) hexane, tert-butylperbenzoate, tert-butylperphenylacetate, tert-butylperisobutyrate, tert
-Butyl per-sec-octoate, tert-butyl perpiparate, cumyl perpiparate, tert-
Peroxide-based crosslinking agents such as butyl perdiethyl acetate and azo compounds such as azobisisobutyronitrile and dimethylazoisobutyrate; dimethacrylate compounds such as ethylene diglycol dimethacrylate and diethylene glycol dimethacrylate; trimethylolpropane trimethacrylate Trimethacrylate compound; polyethylene glycol diacrylate, 1,3
Examples of the crosslinking agent include diacrylate compounds such as butylene glycol diacrylate; triacrylate compounds such as trimethylolpropane triacrylate; divinyl compounds such as divinylbenzene; ethylene glycol dimethacrylate as the crosslinking agent. It is preferable to use a crosslinkable monomer such as the dimethacrylate compound or the divinyl compound such as divinylbenzene. Such a crosslinking agent is usually a monomer component 10
0.05 to 30 parts, preferably 0.5 to 10 parts, is used per 0 parts.

If necessary, a crosslinking aid such as sodium thiosulfate or amine may be used in combination. Further, as the polymer component of the latex awarded in the present invention, such rubber particles may be used alone or in combination of two or more, or may be used in combination with polymer particles other than rubber particles.

2. Non-aqueous dispersion medium The non-aqueous dispersion medium used in the present invention may be any liquid as long as it is a non-aqueous liquid that can be replaced with water. Specific examples of usable non-aqueous dispersion media include n-octane,
Halogen-substituted aliphatic hydrocarbons such as isooctane, nonane, decane, decalin, pinene, and chlorododecane;
Substituted aromatic hydrocarbons such as styrene, chlorobenzene, chlorotoluene, ethylbenzene, diisopropylbenzene, cumene; methanol, ethanol, propanol, isopropanol, butanol, isobutanol, s-butanol, t-butanol, pentanol,
Alcohols such as isopentanol, hexanol, octyl alcohol, benzyl alcohol, tert-butyl catechol, glycerin; acetone, methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, ethyl propyl ketone, cyclopentanone, cyclohexanone, cycloheptanone, diisopropyl Ketones such as ketone, diacetone and isophorone; methyl ethyl ether, diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, diisobutyl ether, di-n-amyl ether, diisoamyl ether, methyl propyl ether, methyl isopropyl ether, methyl butyl ether , Ethyl propyl ether, ethyl isobutyl ether, ethyl n-amyl ether, ethyl isoamyl Lactones of γ- butyrolactone and δ- butyrolactone; ether, tetrahydrofuran, bis (2-cyanoethyl) ether, phenyl ethyl ether, ethers such as dioxane β-
Lactams such as lactams; cyclic aliphatics such as cyclopentane, cyclohexane, cycloheptane and methylcyclopentane; benzene, toluene, o-xylene, m
-Aromatic hydrocarbons such as xylene, p-xylene, ethylbenzene, propylbenzene, isopropylbenzene, butylbenzene, isobutylbenzene, n-amylbenzene; aliphatic hydrocarbons such as heptane, octane, nonane, decane; Dimethylformamide, N-
Chain forms such as methylpyrrolidone and dimethylacetamide
Cyclic amides; Sulfur-containing compounds such as dimethyl sulfoxide; Methylene cyanohydrin, ethylene cyanohydrin, adibonitrile, 3,3′-thiodipropionitrile, acetonitrile, acrylonitrile, and other nitrile group-containing compounds; Ring system compounds; cellosolve acetates such as cellosolve acetate, methyl cellosolve acetate and ethyl cellosolve acetate; glycols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol and butylene glycol; diethylene glycol, diethylene glycol monoethyl ether, diethylene glycol ethyl butyl ether and the like Diethylene glycols; monomethylaniline, dimethylaniline, pipet Amines such as lysine and diethylamine; oxygen-containing heterocyclic compounds such as furan and furfural; epoxy compounds such as propylene oxide; methyl formate, ethyl formate, methyl lactate, ethyl lactate, ethyl lactate, propyl lactate, butyl lactate, methyl benzoate, acetic acid Methyl,
Esters such as ethyl acetate, isopropyl acetate, n-propyl acetate, butyl acetate, methyl acrylate, ethyl acrylate, and butyl acrylate; and the like are exemplified. In addition, a mixture of lacquer, gasoline, naphtha, kerosene, etc. should be used. Can be. Among these, boiling point 80 ℃
As described above, it is preferable to use a non-aqueous dispersion medium having a temperature of 85 ° C. or higher.

3. Production of Non-Aqueous Polymer Dispersion The non-aqueous polymer dispersion of the present invention has a water content of 5% by weight or less, preferably 2% by weight or less, more preferably in the dispersion medium after the above-mentioned non-aqueous dispersion medium is added to the latex. Is obtained by removing up to 0.5% by weight or less. In the present invention, the water may be removed after adding the non-aqueous dispersion medium to the latex as a raw material, and any known method of removing water may be used. In particular,
Examples thereof include a distillation method, an ultrafiltration method, a fractional filtration method and a dispersion medium phase conversion method. The gel content of the rubber particles in the dispersion thus obtained is usually 30% or more, preferably 60% or more, more preferably 80% or more. In the present invention, the gel content is calculated as the insoluble content of the non-aqueous dispersion medium to be used.
After drying at 00 ° C. for 24 hours and measuring the dry weight of the rubber particles, the rubber particles were dried at 25 ° C. using a non-aqueous dispersion medium 100
Immersed in parts by weight for 24 hours, sifted through a 200-mesh sieve, dried solids remaining on the sieve, weighed, and calculated ((dry weight of residual solids on sieve / dry weight of rubber particles) × 100) This is a value calculated from the equation.

[0024]

According to the present invention, since a non-aqueous polymer dispersion can be produced at low cost and easily, adhesives, pressure-sensitive adhesives and coating agents in the field where latex could not be used due to the presence of conventional water. -A non-aqueous polymer dispersion can be used as a binder.

[0025]

The present invention will be described below with reference to examples.
The invention is not limited by these examples. In Examples and Comparative Examples, the gel content, particle size and water content were measured using the following methods or instruments.

(1) Gel content: 1 g of dried and solidified
Was further dried at 100 ° C. for 24 hours, and the dry weight of the polymer was measured. Then, the polymer was cooled to 25 ° C.
Immersed in 100 parts by weight of the non-aqueous dispersion medium to be used at room temperature for 24 hours, sifted through a 200-mesh sieve, dried the solid matter remaining on the sieve, weighed, and calculated by the following formula. (Dry weight of residual solid on sieve / dry weight of polymer)
× 100 (2) Particle size: After removing water in the latex by drying, the major axis and the minor axis of 100 particles were measured with a transmission electron microscope, and the average value was obtained. (3) Moisture; measured by Karl Fischer method.

Example 1 In an autoclave equipped with a stirrer, 1000 parts by weight of water, 700 parts by weight of styrene, 580 parts by weight of butadiene, 350 parts by weight of methyl methacrylate, 90 parts by weight of acrylonitrile, 55 parts by weight of itaconic acid, 4 parts by weight of ammonium lauryl sulfate. And 10 parts by weight of sodium carbonate to prepare a monomer emulsion. Then, into an autoclave equipped with a stirrer, 3.4 liters of water, 10 parts by weight of ethylenediaminetetraacetic acid, 10 parts by weight of ammonium lauryl sulfate,
20 parts by weight of potassium persulfate and 10% by volume of the above monomer emulsion were added, and the mixture was heated to 80 ° C. and reacted for 1 hour while stirring. Next, 80 parts by weight of potassium persulfate was added together with 200 ml of water, and the temperature was maintained at 80 ° C.
While stirring was continued, all remaining monomer emulsion was added. Maintain 80 ℃ and continue stirring for 4 more
After reacting for hours, a milky white latex was obtained (yield: 99
%). The average particle size of the polymer dispersed in this latex was 0.18 μm.

The unreacted residual monomers of the above latex are removed by steam distillation and the pH is adjusted to 7 with lithium hydroxide.
Was prepared. Then, 20 times the total weight of N-methylpyrrolidone (boiling point: 204 ° C.) was added, and water and a portion of N-methylpyrrolidone were evaporated by an evaporator to obtain an N-methylpyrrolidone dispersion having a solid content of 10% by weight. was gotten. The N-methylpyrrolidone dispersion of the polymer thus obtained was translucent and had a water content of 500 ppm. Further, the fact that the polymer particles are moistened by N-methylpyrrolidone approximately 2.5 times as large as that of the latex and dispersed in N-methylpyrrolidone is confirmed by a particle size distribution analyzer (N4Plus manufactured by Coulter, Inc.). Type). The gel content was 96%.

The N-methylpyrrolidone dispersion of the obtained polymer was subjected to a standing test at room temperature for 30 days to evaluate the state of dispersion. As a result, no change was observed in this dispersion even after 30 days, and the dispersion state was extremely good.

Example 2 Various non-aqueous dispersion media shown in Table 1 were added to the commercially available latex shown in Table 1 in the same manner as in Example 1, and then water and a part of the non-aqueous dispersion medium were evaporated using an evaporator. As a result, a non-aqueous polymer dispersion shown in Table 1 was produced. The polymer particle diameter of each of the produced non-aqueous polymer dispersions was 1.1 to 3.5 times that of the latex. It was confirmed by the same method as in Example 1 that all of the non-aqueous polymer dispersions shown in Table 1 were monodispersed in the non-aqueous dispersion medium. The dispersion state was evaluated in the same manner as in Example 1. The results are summarized in Table 1.

[0031]

[Table 1]

The non-aqueous polymer dispersion of the obtained polymer was subjected to a standing test at room temperature for 30 days to evaluate the dispersion state. As a result, no change was observed in each dispersion even after 30 days, and the dispersion state was extremely good.

Claims (3)

[Claims] 1. A method for producing a non-aqueous polymer dispersion, comprising adding a non-aqueous dispersion medium to an aqueous polymer dispersion and removing water in the dispersion medium to 5% by weight or less. 2. The method for producing a non-aqueous polymer dispersion according to claim 1, wherein the polymer has a rubber-like elasticity. 3. The method for producing a non-aqueous polymer dispersion according to claim 1, wherein the non-aqueous dispersion medium has a boiling point of 85 ° C. to 350 ° C. and is liquid at room temperature.