Abstract: A fiber-reinforced rubber composition capable of providing a vulcanizate having an excellent strength and modulus and a production process thereof. This fiber-reinforced rubber composition includes fine short fibers of thermoplastic polymer having ##STR1## groups buried in vulcanizable rubber. The vulcanizable rubber and the thermoplastic polymer are grafted to each other through a resol type alkylphenol formaldehyde resin precondensate or a novolak type phenol formaldehyde resin precondensate at an interface of the fiber. The ratio of the fiber to the vulcanizable rubber (A) 1 to 70 parts by weight based on 100 parts by weight of the rubber in the case of the resol type alkylphenol formaldehyde resin precondensate or (B) 1 to 100 parts by weight based on 100 parts by weight of the rubber in the case of the novolak type phenol formaldehyde resin precondensate.

Abstract: A fiber-reinforced chlorinated polyethylene composition comprises 100 parts by weight of a continuous phase of a chlorinated polyethylene and 2-100 parts by weight of a polyamide dispersed in the continuous phase in a fine short fiber form. Further a process comprises kneading a chlorinated polyethylene and a fiber-formable polyamide at a temperature not lower than the melting point of the polyamide and then stretching the kneaded product to obtain the above fiber-reinforced chlorinated polyethylene composition. When in the above process, the kneading is effected by further adding a reactive binder, there can be obtained a fiber-reinforced chlorinated polyethylene composition wherein the compatibility and dispersion of the fiber-formable polyamide with and in the chlorinated polyethylene are improved.

Abstract: A reinforced rubber composition comprising 100 parts by weight of a vulcanizable rubber including 1 to 100 parts by weight of fine short fibers of a fiber forming polyamide buried therein, and the polyamide and the rubber are bonded through a silane coupling agent. This reinforced rubber composition is suitable for use as automobile tires and the parts thereof and rubber products such as, rubber houses, rubber belts, rubber parts for automobiles, and footwear materials.

Abstract: A fiber-reinforced rubber composition capable of providing a vulcanizate having an excellent strength and modulus and a production process thereof. This fiber-reinforced rubber composition includes fine short fibers of thermoplastic polymer having ##STR1## groups buried in vulcanizable rubber. The vulcanizable rubber and the thermoplastic polymer are grafted to each other through a resol type alkylphenol formaldehyde resin precondensate or a novolak type phenol formaldehyde resin precondensate at an interface of the fiber. The ratio of the fiber to the vulcanizable rubber (A) 1 to 70 parts by weight based on 100 parts by weight of the rubber in the case of the resol type alkylphenol formaldehyde resin precondensate or (B) 1 to 100 parts by weight based on 100 parts by weight of the rubber in the case of the novolak type phenol formaldehyde resin precondensate.

Abstract: A reinforced rubber composition comprising 100 parts by weight of a vulcanizable rubber including 1 to 100 parts by weight of fine short fibers of a fiber forming polyamide buried therein, and the polyamide and the rubber are bonded through a silane coupling agent. This reinforced rubber composition is suitable for use as automobile tires and the parts thereof and rubber products such as, rubber houses, rubber belts, rubber parts for automobiles, and footwear materials.

Abstract: A fiber-reinforced rubber composition capable of providing a vulcanizate having an excellent strength and modulus and a production process thereof. This fiber-reinforced rubber composition includes fine short fibers of thermoplastic polymer having ##STR1## groups buried in vulcanizable rubber. The vulcanizable rubber and the thermoplastic polymer are grafted to each other through a resol type alkylphenol formaldehyde resin precondensate or a novolak type phenol formaldehyde resin precondensate at an interface of the fiber. The ratio of the fiber to the vulcanizable rubber (A) 1 to 70 parts by weight based on 100 parts by weight of the rubber in the case of the resol type alkylphenol formaldehyde resin precondensate or (B) 1 to 100 parts by weight based on 100 parts by weight of the rubber in the case of the novolak type phenol formaldehyde resin precondensate.

Abstract: Disclosed is a process for producing fiber-reinforced elastic articles comprising: 1 to 20 parts by weight of 1,2-polybutadiene fibrils dispersed in a matrix of 100 parts by weight of a rubber material. In the process, the 1,2-polybutadiene in the form of particles are dispersed in the matrix of rubber material; the dispersion is extruded through a die at a temperature of at least 5.degree. C. above the melting point of 1,2-polybutadiene, but not exceeding 240.degree. C., to convert the particles of 1,2-polybutadiene into fibrils; the extruded dispersion is rolled by means of a pair of rollers to increase the degree of molecular orientation of the 1,2-polybutadiene fibrils, and; a composition comprising an elastic material matrix, the 1,2-polybutadiene fibrils dispersed in the elastic material matrix and a vulcanizing agent is shaped and vulcanized at an elevated temperature.

Abstract: Disclosed is a process of producing a fiber-reinforced rubber article having excellent mechanical strength and modulus of elasticity, and exhibiting rubber-like elasticity, by providing a rubber composition from a vulcanizable rubber material, a vulcanizing agent and 1,2-polybutadiene staple fibers in an amount of 1 to 20 parts by weight per 100 parts by weight of the rubber material, shaping and vulcanizing the rubber composition to provide a shaped, vulcanized article in which surface portions of said 1,2-polybutadiene staple fibers are vulcanized and cross-linked to the vulcanized rubber material matrix.

Abstract: Carbon fibers having excellent modulus of elasticity and tensile strength are produced in a high yield by a process wherein polybutadiene fibers are prepared by melt-spinning polybutadiene having at least 85% of vinyl structure, a melting point of at least 100.degree. C and a reduced viscosity of 0.3 to 1.2 dl/g; the fibers are then treated in a solution or suspension of a Lewis acid in an inert organic liquid, whereby the pollybutadiene is cyclized and cross-linked; the polybutadiene fibers treated as mentioned above are further treated in a melted sulphur or a sulphur-containing solution at a temperature of 170 to 300.degree. C, whereby the cyclized and cross-linked polybutadiene is dehydrogenated and aromatized; and the fibers treated as mentioned above are carbonized by raising the temperature thereof to 750.degree. C to 3000.degree. C to form carbon fibers or graphite fibers. If so desired, the ordinary carbon fibers which have been produced at 750 to 1500.degree.