JPH09208617A - Chemically modified diene polymer composition and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively and efficiently produce a diene polymer in which the vinyl groups are chemically modified. SOLUTION: A microparticulate diene polymer composition comprises 70-99wt.% diene polymer microparticles having diene monomer units and a weight-mean particle diameter of 0.05-10μm and 1-30wt.% aqueous surfactant solution to chemically modify the diene polymer. Thus, a chemically modified diene polymer such as an epoxidized diene polymer microparticle composition having a weight-mean particle diameter of 0.05-10μm can be produced.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a particulate rubber polymer composition added to a thermoplastic resin or a thermosetting resin for the purpose of improving impact strength and a method for producing the same. The present invention also relates to a method for producing an elastomer used for tires, shoe soles, tubes, hoses and the like.

[0002]

2. Description of the Related Art Thermoplastic resins such as polystyrene, acrylonitrile / styrene copolymer resin, acrylic resin and thermosetting resins such as epoxy resin and phenol resin, which are used for molding, are required depending on the intended use. In order to ensure high impact resistance strength, it is generally practiced to disperse a diene-based, acrylic-based or silicon-based rubber polymer in a fine particle size.

As a method for dispersing a rubber polymer in a fine particle size, a rubber polymer is dissolved in a monomer before polymerization and is used during polymerization, as is widely used in rubber-reinforced polystyrene resins and acrylic resins. There is a method of depositing and dispersing a rubber polymer by applying the change in the solubility of. In this method, the particle size is limited depending on the relationship between the solubility of the rubber polymer and the pre-polymerization monomer and the state of precipitation of the rubber polymer, and the inside of the dispersion of the rubber polymer is said to be preferable for properties such as impact strength. Also, it is difficult to control the crosslink density, the crosslinked state, etc. because it is necessary to form the crosslinked structure at the interface between the rubber polymer dispersion and the matrix resin in a competitive manner with the precipitation and dispersion of the rubber polymer. .

Another method is to disperse a rubber polymer in a liquid before polymerization or curing by a high mechanical shearing force. In this method, the high shearing force necessary for dispersing fine particles is difficult to apply, there is a limitation in controlling the dispersion state such as the particle size and particle size distribution, and the formation of the crosslinked structure of the rubber polymer is also limited.

In addition to these methods, there is a method of forming fine particles of a rubber polymer in advance and dispersing them in a monomer before a polymerization or curing reaction. The form is slightly different, but ABS
One of the methods is to synthesize polybutadiene by emulsion polymerization, which is generally carried out in resin production, and graft-polymerize styrene / acrylonitrile resin thereto. This method is a good method for uniformly dispersing a rubber polymer having a uniform particle diameter, but it is difficult to efficiently produce fine particles of the rubber polymer, and the rubber weight of the fine particles is also difficult to produce. It is difficult to store and manipulate the coalescence stably.

Further, although it is a good method to produce a rubber polymer in the form of fine particles by emulsion polymerization, a large excess of water is required during emulsion polymerization, and the final objective is to produce a resin. Needs to be removed, which is wasteful in terms of energy and requires complicated operations in terms of steps. Also, with the use of a large excess of water, a large amount of emulsifier is required, and a precipitation step for extracting fine particles is required, and a precipitation agent is used. There is a problem that it is contained as a large amount of impurities.

For the purpose of improving the impact strength, which is the purpose of adding a rubber polymer, a diene polymer is suitable from the viewpoint of rubber properties and the like. However, since the diene polymer has a vinyl group remaining in its molecule, there is an advantage that a graft bond with a matrix resin is easily formed by radical polymerization, but the polymerization reaction is performed at the same time as the addition of the matrix component. When not carried out, or when polymerizing the matrix resin by a polymerization reaction other than radical polymerization, such as polycondensation, ionic polymerization, ring-opening addition polymerization, etc., it is necessary to form a graft bond connecting the interface between the matrix resin and the diene polymer. Have difficulty.

In addition, since the diene polymer has a vinyl group in the molecule, it has a problem that it is easily reacted and is inferior in weather resistance, heat resistance and storage stability.

As a method for solving these problems, attempts have been made to chemically modify a diene polymer. For example, a hydrogenated styrene / butadiene / styrene block copolymer (styrene / ethylene butylene / styrene block copolymer) is used as a resin having improved weather resistance and heat resistance by hydrogenating a vinyl group of a diene polymer. : SEBS)
And hydrogenated styrene / butadiene copolymer rubber (HSBR)
Are commercially available. Also, a method of dissolving a diene polymer in an organic solvent and epoxidizing its vinyl group has been studied for a long time. Although these chemically modified diene-based polymers are excellent in characteristics, they have a drawback that the chemical modification method is complicated and inefficient, resulting in high cost.

In order to solve this high cost, a method has been carried out in which a diene polymer is dispersed in the form of fine particles in an emulsified state and chemically modified by utilizing this wide specific surface area. For example, a method of oxidizing natural rubber in latex to epoxidize it has been developed, and epoxidized natural rubber is commercially available. Also, Rubber Chem. & Tech., 65 , 245-258 (1992) and i
bid, 67 , 288-298 (1994) describes a method of reducing acrylonitrile / butadiene copolymer, styrene / butadiene copolymer and polybutadiene produced by emulsion polymerization in an emulsion state. These methods eliminate complexity from chemical modification in an organic solution and improve efficiency, but inefficiency due to the process of producing diene polymer particles, for example, low concentration of diene polymer. However, the price is still high and the range of use is narrow. Also,
Inconveniences governed by the process of producing a diene polymer, for example, problems caused by the particle size and shape of the diene polymer remain.

On the other hand, a polymerization method utilizing a high internal phase ratio emulsification phenomenon is known as a new type of emulsion polymerization method for efficiently synthesizing fine particle polymer beads using a small amount of water and a surfactant. , US Pat. No. 3,988,508, by K. Lissant, describes high internal phase ratio emulsion polymerization of polyvinyl chloride, polystyrene and the like. According to the polymerization method described here, it is reported that fine particles of polystyrene or polyvinyl chloride can be produced at a usage amount of the surfactant aqueous solution of about 1/10 of the usual amount.

In addition, E. Ruckenstein et al.
ppl.Polym.Sci., 36 (4), 907 (1988) etc. polystyrene,
Concentrated Emulsio for high internal phase ratio emulsion polymerization of polymethacrylic acid alkyl ester, polyacrylic acid ester, etc.
n or Gel-Like-Emulsion polymerization. The researchers also reported that high-concentration polymer particles could be obtained, and polystyrene had an average particle size of 0.1 to 0.1.
It is described that the particle size distribution is very narrow at 0.3 μm.

Further, although these researchers have reported the polymerization of polystyrene, polyvinyl chloride, alkyl acrylate, alkyl methacrylate, etc., their application to diene polymers has not been examined. . Diene monomers generally have a low boiling point and a slow radical polymerization rate, but the heat generation during polymerization is large, so the conditions are different from the polymerization of styrene, vinyl chloride, alkyl acrylate, alkyl methacrylate, etc. Therefore, it is difficult to simply apply this polymerization method to the diene monomer.

The present inventor focused on the fact that the high internal phase ratio emulsion polymerization method is suitable for the production of fine polymer particles, and studied for the purpose of applying it to a wide range of radically polymerizable monomers, particularly diene-based monomers. It was found that in the polymer composition obtained by the present polymerization method, the continuous phase preserves the original function as a grain boundary even after the polymerization, and the dispersed phase particles exist independently. Furthermore, the present inventors have found that a chemically modified diene polymer fine particle composition can be efficiently obtained by chemically modifying this diene polymer fine particle composition, and completed the present invention.

[0015]

An object of the present invention is to efficiently and inexpensively produce a diene polymer in which a vinyl group in a molecule is chemically modified. Another object of the present invention is to provide a fine particle epoxidized diene-based polymer having an epoxy group having high reactivity and being advantageous for forming a graft bond when added to a matrix resin.

[0016]

DISCLOSURE OF THE INVENTION The present invention comprises a diene-based polymer comprising 70 to 99% by weight of diene-based polymer particles, which are fine particles having a weight average particle diameter of 0.05 to 10 μm, and an aqueous surfactant solution. The present invention relates to a method for producing a chemically modified diene polymer, which comprises chemically modifying a diene polymer by adding an aqueous reaction solution to a polymer fine particle composition.

The present invention also has a weight average particle diameter of 0.05 to
It relates to an epoxidized diene polymer fine particle composition characterized by having a size of 10 μm.

What is important in the present invention is that a high-concentration diene-based polymer fine particle composition containing a small amount of an aqueous solution of a surfactant as a continuous phase and a large amount of a diene-based polymer as a dispersed phase is a reaction agent. That is, the diene polymer is chemically modified by the action of an aqueous solution and phase shift of the reactant.

Further, for example, an epoxidized diene polymer fine particle composition produced by chemical modification of a high concentration of diene polymer fine particles according to the method of the present invention has a highly reactive epoxy group in the molecule. Therefore, when it is added to the matrix resin for the purpose of improving impact strength, it is advantageous for forming a graft bond.

The diene polymer composition of the present invention comprises
It is produced by high internal phase ratio emulsion polymerization using a radically polymerizable monomer containing a diene monomer as a dispersed phase. Here, the high internal phase ratio emulsification refers to an emulsified state in which the volume of the dispersed phase is larger than the volume of the continuous phase, but particularly preferably, it is difficult for the spherical dispersed phase to exist as independent spheres in the present invention. A dispersed state in which the dispersed phase occupies 70% by volume or more, particularly 74% by volume or more, which is a value in the case of a finely packed structure of a spherical dispersed phase, is extremely high. The high internal phase ratio emulsion polymerization is to polymerize the radically polymerizable monomer contained in the dispersed phase while maintaining this state.

In the high internal phase ratio emulsion polymerization in the present invention, a radical polymerization initiator is added to a high internal phase ratio emulsion in which a surfactant aqueous solution is used as a continuous phase and a radical polymerizable monomer containing a diene monomer is used as a dispersed phase. Then, the radical polymerizable monomer containing the diene monomer is polymerized.

Here, the surfactant in the aqueous surfactant solution means an organic compound having a function of lowering the surface tension by being dissolved in water. As the surfactant used in the present invention, those which are generally highly hydrophilic and form a so-called O / W type emulsion in which an oil phase is surrounded by an aqueous phase are preferable. As such a surfactant, in the case of an anionic surfactant, a sulfonate such as sodium sulfonate or potassium sulfonate or a carboxylate such as sodium carboxylate or potassium carboxylate is used as a hydrophilic group. Things are preferable,
In the case of a cationic surfactant, it has an ammonium salt such as ammonium chloride, ammonium bromide, or ammonium acetate as a hydrophilic group, or an ammonium salt having a large hydrophilic substituent such as a hydroxyethyl group or an aminoethyl group. Those are preferable. As the nonionic surfactant, the HLB value is used as a measure of the hydrophilic / lipophilic balance, but in the present invention, the HLB value is preferably 13 or more, particularly preferably 15 or more, which is highly hydrophilic. Is preferred.

As the surfactant to be used, for example, as the anionic surfactant, a surfactant used in ordinary emulsion radical polymerization, for example, long-chain fatty acid such as stearic acid, oleic acid, palmitic acid, and lauric acid is used. And long-chain aliphatic carboxylic acid salts such as sodium salts and potassium salts of fatty acids obtained from coconut oil, soybean oil, beef tallow, etc., which are a mixture thereof, and long-chain such as dodecyl, cetyl, stearyl, oleyl, palmityl, and lauryl. Examples thereof include organic compounds generally referred to as anionic surfactants such as sulfonic acid having an alkyl group or benzenesulfonic acid having a long chain alkyl group such as sodium salt and potassium salt.

As the cationic surfactant, stearyltrimethylammonium chloride, palmityltrimethylammonium chloride, cetyltrimethylammonium chloride, trimethylammonium of a long-chain alkyl group mixture derived from a natural product such as coconut oil, soybean oil and beef tallow. Monoalkyl ammonium chloride such as chloride,
Mixture of long-chain alkyl groups derived from natural products such as distearyldimethylammonium chloride, dipalmityldimethylammonium chloride, dicetyldimethylammonium chloride, coconut oil, soybean oil and tallow 2 equivalents of dialkyldimethylammonium chloride or Organic compounds generally called cationic surfactants such as similar long-chain alkyl mono (hydroxyethyl) ammonium chloride and similar long-chain alkylbis (hydroxyethyl) ammonium chloride can be mentioned.

As the nonionic surfactant, ethylene oxide adducts of higher alcohols such as nonylphenol, stearyl alcohol and cetyl alcohol,
Ethylene oxide adduct of long-chain alkyl fatty acid such as stearic acid, palmitic acid, oleic acid, coconut oil fatty acid, soybean oil fatty acid, tallow fatty acid, etc., ethylene oxide adduct of long chain alkylamine derived from coconut oil, soybean oil, tallow, etc. Examples thereof include organic compounds generally called nonionic surfactants.

The aqueous surfactant solution used in the present invention is an aqueous solution in which the above-mentioned surfactant is dissolved in an amount of 0.01 to 25% by weight, preferably 0.1 to 10% by weight. Here, if the concentration of the surfactant is low, it will be difficult to form the high internal phase ratio emulsion of the present invention, and if it is high, it will be difficult to form an aqueous solution of the surfactant. Although the viscosity becomes high and it becomes difficult to form an emulsion having a high internal phase ratio, the concentration of the surfactant is closely related to the physical properties of the surfactant and is not limited to any particular condition. The surfactant aqueous solution is not particularly limited, but may be 25 dyn.
It preferably has a surface tension of not less than / cm. When the surface tension is small, it is often difficult to form an emulsion with a high internal phase ratio, or the produced emulsion with a high internal phase ratio is unstable. In the high internal phase ratio emulsion polymerization of the present invention, a surfactant aqueous solution of 1 to 30% by weight, preferably 5 to 26% by weight is used as a continuous phase. Here, although it is possible to carry out even if the content of the surfactant aqueous solution is large, the concentration at the time of chemical modification becomes low and the efficiency becomes poor. On the other hand, if the content is too small, the stability of the diene polymer fine particle composition becomes low and aggregation easily occurs.

In the radical-polymerizable monomer containing the radical-polymerizable diene-based monomer used in the present invention, examples of the diene-based monomer include butadiene, isoprene and chloroprene. In addition, examples of radically copolymerizable monomers with these diene monomers include, for example, styrene, vinyltoluene, α-methylstyrene,
Aromatic vinyl monomers such as p-butylstyrene and divinylbenzene, vinyl monomers having a nitrile group such as acrylonitrile and methacrylonitrile, methyl methacrylate, ethyl methacrylate, butyl methacrylate,
Hexyl methacrylate, octyl methacrylate, decyl methacrylate, dodecyl methacrylate, stearyl methacrylate, oleyl methacrylate, methacrylic acid alkyl ester monomers such as cetyl methacrylate, ethyl acrylate, butyl acrylate, hexyl acrylate,
Octyl acrylate, decyl acrylate, dodecyl acrylate, stearyl acrylate, oleyl acrylate,
Examples thereof include acrylic acid alkyl ester monomers such as cetyl acrylate.

Further, olefinic monomers such as ethylene, propylene, 1-butene, 1-hexene, 1-octene and vinylcyclohexane, vinyl acetate, vinyl formate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl caprate, Vinyl caprylate, vinyl chloroacetate, vinyl cinnamate, vinyl crotonate, vinyl octanoate, vinyl palmitate, vinyl pivalate, vinyl benzoate, vinyl stearate, vinyl laurate,
Vinyl chloride, vinylidene chloride, vinylidene fluoride, vinylpyrrolidone, vinylcarbazole, methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether,
Vinyl monomers such as phenyl vinyl ether, maleic anhydride, dimethyl maleate, diethyl maleate, dibutyl maleate, dioctyl maleate, monoethyl maleate, monobutyl maleate, phenyl maleimide, ethyl maleimide, butyl maleimide and other maleic acid derivative monomers. , Dimethyl fumarate, diethyl fumarate, dibutyl fumarate, dioctyl fumarate,
Fumarate ester monomers such as monoethyl fumarate, monobutyl fumarate, and monooctyl fumarate may also be used.

In the present invention, the diene monomer is used alone,
Alternatively, a plurality of them are mixed and used. When other radically polymerizable monomers are copolymerized, it is preferable that the radically polymerizable diene-based monomer is contained in an amount of 5% by weight or more, particularly 10% by weight or more. If the amount of the diene-based monomer is small, the properties of the diene-based polymer as a rubber are lost, and the concentration of carbon-carbon double bonds contained in the diene-based polymer is reduced, which makes chemical modification difficult. The effect becomes poor.

The diene polymer fine particle composition used in the present invention contains the diene polymer fine particles in an amount of 70 to 99% by weight, preferably 74 to 95% by weight. Here, if the content of the diene polymer fine particles is small, it can be carried out, but the concentration at the time of chemical modification becomes low and the efficiency becomes poor. On the other hand, when the content is large, the stability of the diene polymer fine particle composition becomes low and aggregation easily occurs.

Examples of the radical polymerization initiator used in the present invention include 2,2'-azobisisobutyronitrile, 2,2'-azobis (2,4-dimethylvaleronitrile) and 2,2'-azobis ( 4-methoxy-2,4
-Dimethylvaleronitrile), 2,2'-azobis (2
-Methylbutyronitrile), 1,1'-azobis (cyclohexane-1-carbonitrile), 2-phenyl-4
-Methoxy-2,4-dimethyl-valeronitrile, 2,
2'-azobis (2,4,4-trimethylpentane),
Oil-soluble azo compounds such as 2,2′-azobis (2-methylpropane) and dimethyl 2,2′-azobisisobutyrate and 1-[(1-cyano-1-methylethyl) azo] formamide dichloride Hydrogenated 2,2'-azobis (2-methyl-N-phenylpropioamide), dichloride Hydrogenated 2,2'-azobis [N- (4-hydroxyphenyl) -2-methylpropioamidine], dichloride Hydrogenated 2,2'-azobis (2-methylpropionamidine), 2,2'-azobis [2- (2-imidazoline 2
-Yl) propane, 2,2'-azobis [2-methyl-
N- (2-hydroxyethyl) propionamide, 4,
Examples thereof include, but are not limited to, water-soluble azo compounds such as 4′-azobis (4-cyanopentanoic acid).

As the radical polymerization initiator, for example, benzyl peroxide, isobutyryl peroxide, octanoyl peroxide, lauroyl peroxide, stearoyl peroxide, tertiary butyl hydroperoxide, cumene hydroperoxide, ditertiary butyl peroxide. It is also possible to use peroxides such as oxides, p-menthane hydroperoxide, potassium persulfate, sodium persulfate, hydrogen peroxide.

The radical polymerization initiator used is used in an amount of 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the high internal phase ratio emulsion. Here, if the radical polymerization initiator is small, the polymerization reaction does not occur or the speed becomes slow, and if the radical polymerization initiator is large, the polymerization initiation efficiency becomes low and at the same time, the amount of impurities contained in the polymer composition increases.

In the present invention, additives for controlling the action of these radical polymerization initiators such as dodecyl mercaptan and trimethylolpropane, which are used for the purpose of controlling the molecular weight of reducing agents and polymers, are also used. It is also possible to use compounds called so-called chain transfer agents such as mercaptans such as tristhiopropionate, disulfides, halogenated hydrocarbons and alcohols.

The diene polymer used in the present invention is a fine particle having a weight average particle diameter of 0.05 to 10 μm, preferably 0.1 to 5 μm, which is measured by dispersing it in water as primary particles. Here, if the weight average particle size is small,
The effect of improving the impact strength when added to the matrix resin becomes poor, and if it is large, the specific surface area of the diene polymer becomes small, and the efficiency of chemical modification becomes poor.

In the present invention, the chemical modification means a chemical reaction of a polymer formed in advance to change the molecular structure of the polymer. Especially as the chemical modification in the present invention, the vinyl group present in the diene polymer molecule,
It refers to changing to a new molecular structure such as ethylene group or epoxy group by reduction reaction or oxidation reaction using a reactant. It also includes the case of hydroformylating a vinyl group.

Further, the chemical modification in the present invention does not necessarily result in the same chemical modification of all vinyl groups present in the diene polymer molecule. For example, it is possible to chemically modify only the vinyl groups present on the surface of the diene polymer fine particles, or the vinyl groups present on the diene polymer fine particles can be optionally chemically modified. It is also possible to chemically modify two or more different vinyl groups.

In the present invention, the reactant means a compound which causes a chemical reaction with the vinyl group in the diene polymer molecule. Examples of such a reaction agent include, but are not limited to, compounds such as performic acid, peracetic acid, perpropionic acid, and perbutyric acid which directly oxidize a vinyl group to epoxidize. In addition, the reaction product reacts with vinyl groups,
For example, there are combinations of hydrogen peroxide and water-soluble fatty acids such as formic acid, acetic acid, propionic acid and butyric acid, and combinations of hydrogen peroxide and hydrazines such as hydrazine and p-toluenesulfonylhydrazide.

In the present invention, the reaction agent is used as an aqueous solution for chemical modification. Here, the aqueous solution indicates a state of being dissolved in water, but the solvent is not always limited to water. For example, water-soluble organic substances such as methanol, ethanol, acetic acid, glycerin and ethylene glycol can be mixed with water and used.

As the reactants in the present invention, not all of the reactants necessary for chemical modification are used as an aqueous solution. For example, a water-soluble transition metal ion may be used as a catalyst when performing chemical modification such as an oxidation reaction or a reduction reaction. In such a case, a reaction of a water-insoluble reducing agent or an oxidizing agent may occur. The agent can be used for chemical modification without being in an aqueous solution.

In the present invention, the amount of the reactant aqueous solution is 1 to 1300 parts by weight, preferably 10 to 500 parts by weight, and more preferably 50 to 200 parts by weight, based on 100 parts by weight of the diene polymer composition. . Here, if the amount of the aqueous solution of the reactant is small, delocalization of the reactant is apt to occur, the efficiency of chemical modification is lowered, and if it is large, the concentration of the diene polymer is lowered, which impairs the object of the present invention.

[0042]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. In the following description,% means% by weight unless otherwise specified.

Example 1 A 300 ml SUS trap can was cooled in a dry ice / methanol bath to liquefy 85 g of butadiene monomer. To this, 1.0 g of azobisisovaleronitrile, which is a radical polymerization initiator, was added and sealed, and the inside of the trap can was replaced with nitrogen. This was left still at room temperature and heated up to 20 ° C. On the other hand, 14 g of a 2% aqueous solution of bis (2-hydroxyethyl) oleylmethylammonium chloride was placed in a 300 ml glass autoclave equipped with a stirrer, the atmosphere was replaced with nitrogen, and the mixture was stirred for 5 minutes. A trap can containing a mixed solution of a butadiene monomer and a radical polymerization initiator was connected thereto, and the mixture was added dropwise with stirring under pressure to obtain a uniform cloudy creamy emulsion composition. The autoclave containing this emulsified composition is kept in a water bath at 50 ° C for 10 hours and then at 60 ° C.
Polymerization was carried out by keeping the temperature in the water bath for 5 hours. The composition after completion of the polymerization was measured at 150 ° C. with an infrared heating type weight loss measuring device, and the weight loss by heating was 14.8% (nonvolatile content 85.2).
%)Met. When 1 g of the obtained white paste-like polybutadiene composition was added to 10 g of pure water, white cloudy streaks were immediately generated and dispersed in water. This liquid was treated with an ultrasonic disperser for 1 hour to be sufficiently dispersed, and the particle size distribution was measured with a model N4SD type particle size measuring instrument manufactured by Coulter, Inc., USA. As a result, the weight average particle diameter was 0.43 μm and the number average particle diameter was 0.34 μm.

10 g of the obtained polybutadiene composition, 1
5 g of 0% aqueous hydrogen peroxide solution and 1 g of 10% aqueous acetic acid solution were placed in a test tube containing a magnetic stirrer, the atmosphere was replaced with nitrogen, and the mixture was stirred and mixed. Heat this in a 50 ° C water bath for 5 hours,
The polybutadiene composition was epoxidized. When the weight loss on heating of the obtained reaction product was measured at 150 ° C., the weight loss on heating was 44.3% (solid content concentration 55.7%). The obtained epoxidized butadiene composition was obtained according to JIS K723.
The epoxy equivalent was measured according to No. 6. As a result, the epoxy content of the reaction mixture was 4.0 equivalents / kg, the chemical modification yield based on hydrogen peroxide was 87%, and 42% of the polybutadiene before chemical modification was epoxidized. I found out. The obtained epoxidized butadiene composition was dispersible in water like the polybutadiene composition before epoxidation, and the particle size distribution was measured using this aqueous dispersion. As a result, the weight average particle diameter was 0.
It was confirmed that the particle size distribution was 44 μm and the number average particle size was 0.34 μm, and the particle size distribution hardly changed due to the chemical modification.

Example 2 A 300 ml SUS trap can was cooled in a dry ice / methanol bath to liquefy 60 g of butadiene monomer. Then, 2 g of azobisisovaleronitrile and 20 g of styrene monomer were added and sealed, and the inside of the trap can was replaced with nitrogen. This was left still at room temperature and heated up to 20 ° C. On the other hand, 20 g of a 5% bis (2-hydroxyethyl) oleylmethylammonium chloride aqueous solution was placed in a 300 ml glass autoclave equipped with a stirrer, the atmosphere was replaced with nitrogen, and the mixture was stirred for 5 minutes. A trap can containing a mixed solution of a butadiene monomer, a styrene monomer, and azobisisovaleronitrile was connected thereto, and the mixture was added dropwise with stirring under pressure to obtain a uniform cloudy creamy emulsion composition. The autoclave containing this emulsified composition is left in a water bath at 50 ° C for 1
Polymerization was carried out by keeping the temperature for 0 hours and then for 5 hours in a water bath at 60 ° C. The composition after completion of the polymerization was measured at 150 ° C. with an infrared heating type heating loss measuring device, and the heating loss was 20.
It was 0% (nonvolatile matter 80.0%). The water content measured by the Karl Fischer method was 18.5.
% By weight. From these, a butadiene monomer and a styrene monomer were polymerized almost quantitatively, and a particulate polymer composition having about 80% by weight of a styrene / butadiene copolymer (styrene / butadiene rubber) as dispersed phase particles was obtained. It was confirmed.

The white paste-like product obtained was redispersed in water as in Example 1. Further, as a result of measuring the particle size distribution in the same manner as in Example 1, the weight average particle size is 0.38 μm.
m, and the number average particle diameter was 0.33 μm.

The polybutadiene composition obtained was used in Example 1.
It was epoxidized by the same operation as. The weight loss on heating measured in the same manner as in Example 1 was 47.2% (solid content concentration 52.8%). The epoxy equivalent of the obtained epoxidized butadiene composition was measured in the same manner as in Example 1. As a result, the epoxy content of the reaction mixture was 2.9 equivalents / kg, and it was epoxidized to the same extent as in Example 1. I found out that Also,
The obtained epoxidized butadiene composition was dispersible in water in the same manner as in Example 1, and the values of the weight average particle diameter and the number average particle diameter measured using this aqueous dispersion were the same as those before chemical modification. The values were almost the same, and it was confirmed that the particle size distribution hardly changed by the chemical modification.

[0048]

EFFECTS OF THE INVENTION As is clear from the examples, a chemically modified diene polymer composition containing a high concentration of fine particles and a chemically modified diene polymer which can be redispersed in primary particles according to the present invention. Can be easily manufactured at low cost.

Claims (3)

[Claims] 1. 70 to 99% by weight of polymer fine particles, which are fine particles containing a diene monomer unit and having a weight average particle size of 0.05 to 10 μm, and 1 to 30% by weight of an aqueous surfactant solution.
A method for producing a chemically modified diene polymer, which comprises chemically modifying the diene polymer by adding an aqueous solution of a reactant to the diene polymer fine particle composition comprising 2. The method for producing a chemically modified diene polymer according to claim 1, wherein the reactive aqueous solution contains hydrogen peroxide. 3. An epoxidized diene polymer fine particle composition having a weight average particle diameter of 0.05 to 10 μm obtained by the production method according to claim 1.