JPH1077368A - Rubber composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition capable of giving a vulcanized rubber excellent in slipperiness, stain resistance, etc., by compounding the copolymer of a specific organopolysiloxane with one or more other radically polymerizable monomers. SOLUTION: This rubber composition comprises (A) 100 pts.wt. of natural rubber and/or a synthetic rubber and (B) 0.1-50 pts.wt. of the copolymer of an organopolysiloxane of the formula [R is a monovalent 1-20C hydrocarbon or a monovalent 1-20C halogenated hydrocarbon; X is a monovalent radically polymerizable group; (n) is an integer of 5-200] with one or more other radically polymerizable monomers. The organpolysilozane and the other radically polymerizable monomers are preferably copolymerized at a compounding weight ratio of 5:95 to 95:5. The rubber composition can be processed in molded products excellent in slipperiness, stain resistance, blocking resistance and abrasion resistance, and is suitably used for forming seal members, gasket members, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a synthetic rubber or natural rubber composition, particularly a copolymer of a specific organopolysiloxane and another radical polymerizable monomer.
The present invention relates to a rubber composition that gives a vulcanized rubber having excellent slidability and stain resistance.

[0002]

2. Description of the Related Art Rubber generally has so-called rubber elasticity, and is excellent in extensibility, resilience, rebound resilience, tear strength, flexibility, etc., but is inferior in slidability and abrasion resistance. Depending on the degree, the adhesive has a disadvantage of being inferior in stain resistance and blocking resistance. For example, ethylene-propylene rubber has been used for glass runs and window frames because of its excellent weather resistance, heat resistance, and workability. However, it has poor slidability, and generates squeak noise due to vibration. In order to prevent this, flocking is applied to the sliding part of the glass (Japanese Patent Laid-Open No. 2-20
No. 424), it is necessary to form a urethane lubricating layer (see Japanese Patent Application Laid-Open No. Hei 3-61329), so that the process becomes long and productivity is not good. Further, acrylic rubber has oil resistance and weather resistance. Although it is excellent in heat resistance, ozone resistance and heat resistance, it has problems to be improved according to each rubber, such as poor contamination resistance in addition to slidability. As one method of solving this problem, an acryl-modified organopolysiloxane obtained by graft-copolymerizing an organopolysiloxane and a (meth) acrylic acid ester with a rubber is blended (Japanese Patent Laid-Open No. 6-15 / 1990).
Although a method has been proposed, since it contains a small amount of low molecular weight organopolysiloxane oligomer, the effect on slidability is recognized, but the stain resistance is not good. As described above, there is a problem that rubber is generally inferior in characteristics represented by slidability and stain resistance.

[0003]

SUMMARY OF THE INVENTION Under the circumstances described above, the present invention has been made to provide a rubber composition which gives a vulcanized rubber having excellent sliding properties and stain resistance.

[0004]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, if a copolymer of a specific organopolysiloxane and another radical polymerizable monomer is blended, It has been found that the present invention is achieved. That is, the rubber composition of the present invention has solved the above-mentioned problems, and (1) synthetic rubber and / or natural rubber
For 100 parts by weight, (2) general formula (I)

Embedded image (Wherein, R represents the same or different monovalent hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, X represents a monovalent radical polymerizable group, and n represents an integer of 5 to 200) ) And 0.1 to 50 parts by weight of a copolymer of an organopolysiloxane and another radical polymerizable monomer.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. The component (1) constituting the composition of the present invention is a synthetic rubber and / or a natural rubber as a raw rubber, and various kinds of conventionally known synthetic rubbers, for example, styrene-butadiene rubber, acrylonitrile- Butadiene rubber, hydrogenated acrylonitrile-butadiene rubber, butadiene rubber, isoprene rubber, chloroprene rubber, ethylene-propylene rubber, ethylene-propylene-diene rubber, acrylic rubber, ethylene-acrylate rubber, ethylene-vinyl acetate rubber, urethane rubber, polysulfide Rubber, chlorosulfonated polyethylene rubber, chlorinated polyethylene rubber, fluorine rubber, epichlorohydrin rubber and the like can be mentioned. These synthetic rubbers or natural rubbers can be used in combination of two or more as necessary.

The component (2) in the composition of the present invention is represented by the general formula (I)

Embedded image (However, R in the formula is the same or different 1 to 20 carbon atoms.
X represents a monovalent radical or a halogenated hydrocarbon group, X represents a monovalent radically polymerizable group, and n represents an integer of 5 to 200. A copolymer of the organopolysiloxane represented by the formula (1) and another radical polymerizable monomer is used. The organopolysiloxane represented by the general formula (I) can be produced by a method disclosed in JP-A-59-78236 and JP-A-6-228316. Specific examples of R in the general formula (I) include a methyl group, an ethyl group,
Propyl group, isopropyl group, n-butyl group, alkyl group such as n-hexyl group, phenyl group, aryl group such as tolyl group, phenethyl group, aralkyl group such as benzyl group,
Non-radical polymerizable groups such as halogenated alkyl groups such as 3,3,3-trifluoropropyl group and 3-chloropropyl group are exemplified, and methyl, butyl and phenyl groups are industrially preferable. Further, from the viewpoint of imparting slidability and stain resistance, it is preferred that 50 mol% or more of all Rs are methyl groups.

X in the general formula (I) is a monovalent radically polymerizable group, which includes an organic group to which a radically copolymerizable substituent is bonded.

Embedded image (In the formula, R ¹ represents a divalent organic group having 3 to 20 carbon atoms which may contain a hetero atom, and R ² represents a hydrogen atom or a methyl group.) As R ¹ in the formula, for example,-(CH ₂ )
_3- , -CH ₂ CH (CH ₃ ) CH ₂ -,-(CH ₂ ) ₄ -,-(CH ₂ ) ₆ -,-(CH ₂ ) ₃ O
(CH ₂ ) ₂ -,-(CH ₂ ) _3- (CH ₂ ) ₂ O- (CH ₂ ) _2- and the like.
The number of n in the general formula (I) is preferably an integer of 5 to 200,
If it is less than 5, the performance as silicone, that is, sliding property,
Poor stain resistance, etc.If it exceeds 200, it will be difficult to copolymerize with other radically polymerizable monomers, unreacted organopolysiloxane will increase, bleed on the vulcanized rubber surface, decrease in strength, etc. Is not preferred. The organopolysiloxane represented by the general formula (I) is a radically polymerizable silicone macromonomer, and specific examples thereof include the following. However, it is not limited to these.

[0008]

Embedded image

[0009]

Embedded image

[0010]

Embedded image

Other radically polymerizable monomers copolymerizable with the organopolysiloxane represented by the general formula (I) include:
Acrylic esters, methacrylic esters, styrenes, and vinyl esters are suitable, and two or more of them can be used in combination. Specific examples thereof include methyl (meth) acrylate, ethyl (meth) acrylate,
alkyl (meth) acrylates such as n-butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate; 2-hydroxyethyl (meth) acrylate, 2
Hydroxyalkyl (meth) acrylates such as -hydroxypropyl (meth) acrylate and 2-hydroxybutyl (meth) acrylate; trifluoropropyl (meth) acrylate, perfluorobutylethyl (meth) acrylate, perfluorooctylethyl (meth) Fluorine-substituted alkyl (meth) acrylates such as acrylate; epoxy group-containing monomers such as glycidyl (meth) acrylate, allyl glycidyl ether, 3,4-epoxycyclohexylmethyl (meth) acrylate; methoxyethyl (meth) acrylate, butoxy Alkoxyalkyl (meth) acrylates such as ethyl (meth) acrylate; halogen-containing monomers such as vinyl monochloroacetate and 2-chloroethyl vinyl ether; styrene, α
-Methylstyrene, 4-methylstyrene, 3-methylstyrene, 4-vinylanisole, 2-chlorostyrene,
Styrenes such as 3-chlorostyrene and 4-chlorostyrene; and vinyl esters such as vinyl acetate, vinyl propionate and vinyl laurate.

Further, radical polymerizable monomers other than those described above can be copolymerized within a range that does not impair the effects of the present invention. Examples of such a monomer include acids such as maleic acid, fumaric acid, acrylic acid, and methacrylic acid; acrylamides such as acrylamide and N-methylolacrylamide; 3-trimethoxysilylpropyl (meth) acrylate; Triethoxysilylpropyl (meth) acrylate, 3-dimethoxymethylsilylpropyl (meth) acrylate, vinyltriethoxysilane, 4-vinylphenyltrimethoxysilane, vinylmethyldimethoxysilane, 4-trimethoxysilyl-1
Radical polymerizable silane compounds such as -butene and 6-trimethoxysilyl-1-hexene; acrylonitrile, vinyl chloride, vinylidene chloride, vinyl pyridine, vinyl pyrrolidone, vinyl alkyl ethers, and one radical polymerizable group in the molecule. Radical polymerizable macromonomers such as polyoxyalkylene and polycaprolactone, and crosslinkable monomers such as ethylene glycol di (meth) acrylate, butanediol di (meth) acrylate, divinylbenzene, and allyl methacrylate.

Further, it is possible to use an antioxidant or a light stabilizer having a radical polymerizable double bond for the purpose of further improving the weather resistance. Such monomers include:
2,2,6,6-tetramethyl-4-piperidinyl acrylate, 2,2,6,6-tetramethyl-4-piperidinyl methacrylate, 1,2,2,6,6-pentamethyl-4- Piperidinyl acrylate, 1,2,2
6,6-pentamethyl-4-piperidinyl methacrylate and the like are exemplified.

The compounding ratio in the copolymerization of the organopolysiloxane represented by the general formula (I) described above and another radical polymerizable monomer (II) copolymerizable with the organopolysiloxane is (I ) / (II) = (5-95) /
(5-95) (% by weight). If the compounding amount of (I) is less than 5% by weight, the effect of improving the slidability and stain resistance is insufficient, and if it exceeds 95% by weight, the compatibility with rubber deteriorates and the appearance is impaired.

As the method of copolymerizing (I) and (II), known polymerization methods such as emulsion polymerization, suspension polymerization, microsuspension polymerization, solution polymerization, and bulk polymerization can be used. Is an emulsion polymerization method, a suspension polymerization method,
Microsuspension polymerization is preferred. As a polymerization initiator for copolymerization, a usual radical polymerization initiator can be used, and benzoyl peroxide, dicumyl peroxide, lauroyl peroxide, 2,2
2′-azobis- (2-methylbutyronitrile), 2,
Oil-soluble radical polymerization initiators such as 2'-azobisisobutyronitrile, potassium persulfate, ammonium persulfate, aqueous hydrogen peroxide, t-butyl hydroperoxide, t-
Butyl peroxypivalate, 2,2'-azobis-
Water-soluble radical polymerization initiators such as (2-N-benzylamidino) propane hydrochloride are exemplified. Further, if necessary, a redox system using a reducing agent such as sodium acid sulfite, Rongalit, or L-ascorbic acid can be used.

Surfactants used in emulsion polymerization and microsuspension polymerization include alkylbenzene sulfonates such as sodium dodecylbenzenesulfonate, alkylnaphthalene sulfonates, alkyl sulfosuccinates, and polyoxyethylene alkylphenyl ethers. Anionic surfactants such as sodium sulfate and sodium lauryl sulfate; polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, sorbitan fatty acid ester, ethylene oxide
Nonionic surfactants such as propylene oxide block copolymers; and nonionic surfactants such as alkyltrimethylammonium chloride and alkylbenzylammonium chloride.
Examples include cationic surfactants such as secondary ammonium salts and alkylamine salts.

Further, JP-A-54-144317, JP-A-55-144317
115419, JP-A-62-34947, JP-A-58-203960, JP-A-4
-53802, JP-A-62-104802, JP-A-49-40388, JP-A-52
-134658, reactive anionic surfactants described in JP-B-49-46291; JP-A-53-126093;
56-28208, JP-A-4-50204, JP-A-62-104802, JP-A
Reactive nonionic surfactants described in JP-A-50-98484; reactive cationic surfactants having a quaternary ammonium salt or a tertiary amine salt and a radical polymerizable group are exemplified. Examples of the suspending agent in the suspension polymerization method include polyvinyl alcohol, carboxymethyl cellulose, polyalkylene oxide, polyacrylic acid, and polyacrylate.

The polymerization temperature is preferably in the range of 10 to 150 ° C., particularly 30 to 90 ° C. Under this temperature condition, the polymerization reaction can be completed in about 3 to 10 hours. In the case of the emulsion polymerization method or the micro-suspension polymerization method, the copolymer polymerized in this manner coagulates the emulsion after polymerization.
It is washed, dehydrated and dried, or directly dried with a spray drier to obtain a solid copolymer. Further, in the case of the suspension polymerization method, dehydration, washing and drying are performed, and in the case of the solution polymerization method, the solid copolymer is precipitated in a poor solvent and filtered and dried, or directly dried with a spray drier to obtain a solid copolymer.
The obtained solid copolymer is pulverized by a hammer mill, a jet mill, or the like, if necessary, to obtain a fine particle copolymer.

The copolymer of the above-mentioned component (2) of the organopolysiloxane and the other radical polymerizable monomer is used in an amount of 100 parts by weight of synthetic rubber and / or natural rubber.
0.1 to 50 parts by weight, preferably 0.5 to 20 parts by weight. If the amount is less than 0.1 part by weight, the sliding effect of the molded article obtained from the composition, the effect of improving the stain resistance is small, and the effect of the present invention is not sufficiently exhibited. Improvement is hardly recognized, and if it is excessively compounded, the inherent properties of the rubber are impaired.

The composition of the present invention can be vulcanized by adding and mixing a vulcanizing agent, a vulcanization accelerator and other vulcanization aids which are generally used according to the type of the component (1). It becomes possible. Further, if desired, various additives added in ordinary rubber compounding, for example, fillers, antioxidants, plasticizers, process oils, coloring agents, foaming agents, etc. may be added within a range not to impair the object of the present invention. it can. Also,
By imparting the same type of vulcanizing functional group as the component (1) to the component (2) by copolymerization, the components (1) and (2) can be co-vulcanized. Better.

The method for preparing the composition of the present invention is not particularly limited, and any of the conventionally known methods, for example, the above (1),
(2) The components and various additional components (but excluding vulcanizing aids such as vulcanizing agents and vulcanization accelerators) are used at predetermined ratios, respectively.
A rubber composition can be produced by uniformly kneading these with a kneading machine such as a mixing roll, a pressure kneader, or a Banbury mixer. Further, after vulcanizing agent, vulcanization accelerator and other vulcanization aids are uniformly mixed using the kneading machine to the composition thus obtained, a conventional extrusion molding machine, injection molding machine, It can be appropriately molded and vulcanized into a desired shape using a pressure molding machine or the like. The molding vulcanization conditions are not particularly problematic as the same conditions as in the case of the composition formulated without blending the component (2).

The composition of the present invention imparts slidability and stain resistance to molded articles, improves blocking resistance and abrasion resistance, and has the effect of increasing the discharge speed during extrusion molding.
The mold releasability is improved, and the productivity is improved together with the characteristics. Therefore, the composition of the present invention is suitable for various uses such as a sealing material, a gasket material, and an extruded product.

[0023]

EXAMPLES The present invention will be described more specifically based on examples. In addition, the part in an example represents a weight part, and% represents weight%. Production Example 1 In a polymerization vessel equipped with a stirrer, a condenser and a thermometer,
After charging 100 parts of toluene and raising the temperature to 95 ° C., 20 parts of methyl methacrylate, 10 parts of styrene, and 20 parts of butyl acrylate
Part, general formula

Embedded image A mixture of 50 parts of an organopolysiloxane represented by the following formula and a mixture of 2.7 parts of perbutyl O (trade name, manufactured by NOF Corporation) and 10 parts of toluene were added dropwise over 4 hours while maintaining the inside temperature at 95 ° C. And a mixture of 0.3 parts of perbutyl O and 2 parts of toluene was added thereto.
After aging for a period of time, a polysiloxane copolymer solution was obtained. This solution was added to a large amount of n-hexane to precipitate a copolymer, which was filtered and dried, and the polysiloxane copolymer (C-
1) was obtained.

Production Example 2 A polymerization vessel equipped with a stirrer, a condenser, a thermometer and a nitrogen gas inlet was charged with 200 parts of deionized water, and then 0.15 parts of Poval B-17R and 0.05 parts of 24 W of the same (both were electrochemically treated). (Trade name, manufactured by the same company), and dissolved while stirring, followed by purging with nitrogen. Then, the temperature in the vessel was adjusted to 75 ° C. After adding 0.1 part of the polymerization initiator azobisisobutyronitrile, a mixture of 30 parts of methyl methacrylate, 20 parts of n-butyl methacrylate, 20 parts of butyl acrylate and 30 parts of the same organopolysiloxane used in Production Example 1 was added. While maintaining the temperature in the vessel at 75 ° C., polymerization was carried out dropwise over 3 hours, followed by aging for 2 hours to complete the reaction, thereby obtaining a suspension of a spherical polymer having a particle size of about 1 mm. This suspension was washed with water, dehydrated and dried to obtain a polysiloxane copolymer (C-2).

Production Example 3 A polymerization vessel equipped with a stirrer, a condenser, a thermometer and a nitrogen gas inlet was charged with 50 parts of deionized water, purged with nitrogen, heated to 60 ° C., and then 20 parts of methyl methacrylate, butyl Acrylate 72 parts and general formula

Embedded image A mixture of 8 parts of an organopolysiloxane represented by the following formula was added to an aqueous solution of 50 parts of deionized water, 2 parts of sodium lauryl sulfate, and 2 parts of Neugen EA-170 (trade name, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.). Monomer emulsion obtained by emulsifying with a mixer 1
Charge 5 parts out of 54 parts, and then add t as a polymerization initiator.
0.3 parts of butyl hydroperoxide (purity 70%),
Rongalit 0.17 parts, 1% aqueous solution of disodium ethylenediaminetetraacetate 0.3 parts, 1% aqueous solution of ferrous sulfate 0.1
After 30 minutes, 149 parts of the remaining monomer emulsion was added dropwise over 3 hours while keeping the temperature in the vessel at 80 ° C., and the mixture was aged for 1 hour. To complete the reaction. The obtained emulsion is diluted with an equal amount of deionized water, and a 20% aqueous solution of sodium sulfate is added at 80 ° C. to coagulate the emulsion, washed with water, dehydrated and dried to obtain a polysiloxane copolymer (C- 3) was obtained.

Production Example 4 A polymerization vessel equipped with a stirrer, a condenser, a thermometer and a nitrogen gas inlet was charged with 50 parts of deionized water, purged with nitrogen, heated to 60 ° C., and then 20 parts of styrene and methyl methacrylate. 43 parts, 27 parts of butyl acrylate, 10 parts of the same organopolysiloxane used in Production Example 3, 1 part of a radical-reactive surfactant Aqualon HS-10, Aqualon RN
-20 parts of a mixture of 3 parts (all manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name) was added to 50 parts of deionized water, and then emulsified with a homomixer. Then, as a polymerization initiator, 0.3 part of t-butyl hydroperoxide (purity 70%), 0.17 part of Rongalit, 0.3 part of a 1% aqueous solution of disodium ethylenediaminetetraacetate, 0.1 part of a 1% aqueous solution of ferrous sulfate were added. Start polymerization by adding
After 、 minutes, 149 parts of the remaining monomer emulsion is
While maintaining the temperature at ° C., the mixture was added dropwise over 3 hours to carry out polymerization and aged for 1 hour to complete the reaction. The obtained emulsion is diluted with an equal amount of deionized water, and a 20% aqueous solution of sodium sulfate is added at 80 ° C. to coagulate the emulsion, washed with water, dehydrated and dried to obtain a polysiloxane copolymer (C- 4) was obtained.

Production Example 5 1,500 parts of octamethylcyclotetrasiloxane, 1.2 parts of methacryloxypropylmethylsiloxane and 1,5 parts of pure water
Then, 15 parts of sodium lauryl sulfate and 10 parts of dodecylbenzenesulfonic acid were added thereto, and the mixture was emulsified by stirring with a homomixer, and then passed twice through a homogenizer at a pressure of 3,000 psi to form a stable emulsion. Had made. Then, the emulsion was heated at 70 ° C. for 12 hours, cooled to 25 ° C., aged for 24 hours, adjusted to pH 7 with sodium carbonate, and blown with nitrogen gas for 4 hours, followed by steam distillation. Volatile siloxane is distilled off,
Next, pure water was added to adjust the non-volatile content to 45% to obtain an emulsion of an organopolysiloxane containing 0.03 mol% of methacryl groups. In a polymerization vessel equipped with a stirrer, a condenser, a thermometer and a nitrogen gas inlet, 1,110 parts of the organopolysiloxane emulsion obtained above (organopolysiloxane content: 500 parts) and 1,053 parts of pure water are charged, and the mixture is placed under a nitrogen gas stream. After adjusting the inside of the vessel to 10 ° C, 1.0 part of t-butyl hydroperoxide, L-ascorbic acid
Add 0.5 part and 0.2 part of a 1% aqueous solution of ferrous sulfate, and then maintain methyl methacrylate 2 at a temperature of 30 ° C.
A mixture of 10 parts and 4.5 parts of 2-hydroxyethyl methacrylate was added dropwise over 3 hours to polymerize, and after completion of the addition, stirring was further continued for 1 hour to complete the reaction. The emulsion of the obtained graft copolymer had a solid content of 30%. Then, 1,000 parts of this emulsion was charged into a vessel equipped with a stirrer and heated to 60 ° C. A solution prepared by dissolving 92 parts of sodium sulfate in 563 parts of pure water was added thereto to precipitate an acryl-modified organopolysiloxane, followed by filtration and washing with water. After drying at 60 ° C., an acrylic-modified polysiloxane copolymer (C-5) was obtained.

Example 1 1 part of stearic acid was added to 100 parts of ethylene-propylene rubber (EPT # 3045, manufactured by Mitsui Petrochemical Co., Ltd.)
Antioxidant (Irganox # 1010, Ciba-Geigy, trade name) 1 part, zinc oxide 5 parts, HAF carbon 60
Parts, 20 parts of a paraffinic process oil, and 5 parts of the polysiloxane copolymer C-1 obtained in Production Example 1, were sufficiently kneaded with a pressure kneader, and then vulcanized on an 8-inch roll to the obtained kneaded material. 1.5 parts of Accelerator Noxeller TS (Ouchi Shinko Chemical Co., Ltd., trade name), 0.5 parts of vulcanization accelerator Accel M (Kawaguchi Chemical Co., Ltd., trade name) and 1.5 parts of sulfur are uniformly kneaded to form a roll sheet molded product. This was press-vulcanized at 160 ° C. for 30 minutes to prepare a vulcanized sheet having a thickness of 2 mm. The vulcanized sheet was measured for vulcanization properties according to the measurement method of JIS K-6301. Further, the static friction coefficient, the dynamic friction coefficient, and the contamination were measured by the following methods. The results were as shown in Table 1.

1) Coefficient of static friction and coefficient of dynamic friction After polishing the surface of the vulcanized sheet with sandpaper AA-180, a 10φ × 15 SUS cylinder was used using a friction tester Haydon-14 (trade name, manufactured by Shinto Kagaku). The static friction coefficient and the dynamic friction coefficient were measured under the conditions of a body, a load of 50 g, and a tensile speed of 100 mm / min. 2) Contamination Dust, ash, and lint were adhered to the surface of the sample, and the adhered surface was wiped off with a clean swarf cloth. The number of times until the adhered material was removed was measured, and evaluated according to the following criteria. A: No staining is observed after 1-2 times. B: No stain is observed after 3 to 4 times. C: No stain is observed after 5 times.

Examples 2 to 5 Vulcanized sheets were prepared in the same manner as in Example 1 except that various polysiloxane copolymers shown in Table 1 were blended in accordance with the amounts shown in the table, and vulcanized physical properties were obtained. , The coefficient of static friction and the coefficient of dynamic friction, and the stainability were measured in the same manner, and the results are shown in Table 1.

Comparative Example 1 A vulcanized sheet was prepared in the same manner as in Example 1 except that the polysiloxane copolymer was not added, and its vulcanization properties, static friction coefficient and dynamic friction coefficient, and stainability were also the same. The results are shown in Table 1.

[0032]

[Table 1]

Example 6 Acrylic rubber (RV-1040, manufactured by Nissin Chemical Co., Ltd., trade name) 1
For 00 parts, 1 part of stearic acid, 40 parts of FEF black,
Nocrack # 224 (made by Ouchi Shinko Chemical Co., Ltd.) 1.5
Part, 10 parts of the polysiloxane copolymer C-3 obtained in Production Example 3.
After kneading with a pressure kneader, 2 parts of a vulcanization accelerator Noxeller PZ (trade name, manufactured by Ouchi Shinko Chemical Co., Ltd.) are uniformly kneaded on an 8-inch roll, and the mixture is rolled. A sheet molded product was prepared and vulcanized under pressure at 170 ° C. for 10 minutes, followed by post-vulcanization at 170 ° C. for 4 hours to prepare a vulcanized sheet having a thickness of 2 mm. With respect to this vulcanized sheet, the vulcanization properties, static friction coefficient and dynamic friction coefficient, and contamination were measured in the same manner as in Example 1. The results were as shown in Table 2.

Comparative Example 2 A vulcanized sheet was prepared in the same manner as in Example 6 except that the polysiloxane copolymer was not added, and its vulcanization properties, static friction coefficient and dynamic friction coefficient, and stainability were also the same. And the results are shown in Table 2.

Comparative Example 3 The procedure of Example 6 was repeated, except that the acrylic-modified polysiloxane copolymer C-5 obtained in Production Example 5 was used instead of the polysiloxane copolymer C-3. A vulcanized sheet was prepared in the same manner as above, and the vulcanized physical properties, the static friction coefficient and the dynamic friction coefficient, and the contamination were measured in the same manner. The results are shown in Table 2.

[0036]

[Table 2]

[0037]

According to the present invention, the slidability is extremely excellent, the contamination itself is small, the blocking resistance and abrasion resistance are excellent, and there is almost no bleeding. The present invention provides a rubber composition from which a molded product free from contamination can be obtained. Further, the composition of the present invention has an increased discharge speed at the time of extrusion molding, and has improved mold release properties.

Claims (5)

[Claims] (1) 100 parts by weight of synthetic rubber and / or natural rubber, and (2) general formula (I) (Wherein, R represents the same or different monovalent hydrocarbon group or halogenated hydrocarbon group having 1 to 20 carbon atoms, X represents a monovalent radical polymerizable group, and n represents an integer of 5 to 200) A rubber composition comprising 0.1 to 50 parts by weight of a copolymer of an organopolysiloxane represented by the formula (1) and another radical polymerizable monomer. 2. The organopolysiloxane has a general formula: (Wherein, R ¹ represents a divalent organic group having 3 to 20 carbon atoms which may contain a hetero atom, and R ² represents a hydrogen atom or a methyl group. R, n
Is the same as in claim 1. However, 50 mol% or more of R is a methyl group. The rubber composition according to claim 1, which is represented by the following formula: 3. The organopolysiloxane has a general formula: (Wherein R and n are the same as in claim 1;
Mole% or more is a methyl group. The rubber composition according to claim 1, which is represented by the following formula: 4. The compound (organic polysiloxane) and another radically polymerizable monomer in a mixing ratio (weight ratio) of 5: 5.
4. A copolymer which is copolymerized at 95 to 95: 5.
The rubber composition as described in the above. 5. The rubber composition according to claim 1, wherein the other radically polymerizable monomer contains a (meth) acrylic acid ester as a main component.