Abstract: Rubber modified styrene-acrylonitrile polymers (ABS) having three different types of rubber particles. One type is small, usually emulsion-produced particle. The second is a large emulsion-produced particle. The third is a large, mass-produced particle. Such compositions exhibit good combinations of toughness and gloss.

Abstract: Statistical copolymers of from 85 to 52% by weight of a conjugated diene, from 15 to 48% by weight of at least one unsaturated nitrile and from 0 to 10% by weight of further monomers, copolymerizable with diene and nitrile, which have a molecular weight M.sub.n of from 0.5 to 30 kg/mol and a degree of hydrogenation of the double bonds of greater than 80%, give nitrile rubbers, which are mixed and colvulcanized with these copolymers, an increased ozone resistance.

Abstract: Co-vulcanizates having good mechanical properties are obtained from mixtures of: (a) from 35 to 5%, by weight, of hydrocarbon elastomers; (b) from 65 to 95%, by weight, of nitrile group-containing elastomers having from 25 to 140 nitrile nitrogen atoms and less 12 double bonds per 1000 carbon atoms; by radical cross-linking.

Abstract: A process for the production of a pulverulent mixture consisting of(A) from 60 to 99 parts by weight of a brittle copolymer consisting of acrylonitrile and styrene, .alpha.-methylstyrene, methyl methacrylate or mixtures thereof, and(B) from 1 to 40 parts by weight of a flexible rubber-elastic polymer,by coagulating, in a first stage, a latex of (A) or a mixture of a latex of (A) and a part of a latex of (B), adding, in a second stage, the latex of (B) or the remaining part of the latex of (B), so that the desired quantity ratio of (A) to (B) is attained, and, in a third stage, separating the precipitated mixture of (A) and (B) from the aqueous phase, and drying it.

Abstract: The method of producing a rubber compound having high green strength comprising providing separate rubber components one of which contains a tertiary amine component bound therein and the other of which contains a halogen cross linking agent bound therein, and blending the two rubber components to form a rubber blend having high green strength.

Abstract: An oil-resistant rubber composition comprising 98 to 50 parts by weight of (1) a partially hydrogenated unsaturated nitrile/conjugated diene copolymer rubber in which at least 50% of units derived from the conjugated diene are hydrogenated, and 2 to 50 parts by weight of (2) a liquid copolymer having a number average molecular weight of 500 to 10,000 obtained by copolymerizing 10 to 80% by weight of a conjugated diene, 10 to 70% by weight of an unsaturated nitrile and 0 to 20% by weight of a vinyl monomer copolymerizable with these monomers, the total amount of the components (1) and (2) being 100 parts by weight.

Abstract: Thermoplastic rubber blends are described comprising monoolefin rubber and nitrile rubber which blends exhibit extraordinary oil resistance.

Abstract: A transparent resin composition comprising (1) 6 to 100% by weight of a nitrile graft copolymer comprising a rubber trunk polymer and a branch polymer grafted thereon, which has been obtained by graft-polymerizing onto the rubber trunk polymer a monomer mixture containing an unsaturated nitrile and a monomer copolymerizable therewith, and (2) 0 to 94% by weight of a random copolymer of an unsaturated nitrile and a monomer copolymerizable therewith, the resin components of the resin composition other than the rubber trunk polymer constituting a matrix resin, wherein(a) said rubber trunk polymer has a glass transition temperature of not higher than 0.degree. C. and constitutes 4 to 25% by weight of the resin composition,(b) the unsaturated nitrile constitutes 25 to 90% by weight of the matrix resin in the resin composition,(c) the difference in the refractive indexes between the rubber trunk polymer and the matrix resin is not more than 0.

Abstract: In the process of melting a blend of nitrile polymer and lubricous additive with a screw-plasticizing unit, the improvement which involves having an absorptive anti-slip agent such as rubber crumb in admixture with the blend when charging the plasticator to minimize feeding problems.

Abstract: Improved rubbery compositions comprise vinyl chloride polymers, butadiene-acrylonitrile polymers and butadiene-styrene-tertiary amine polymers. Such compositions may be compounded and vulcanized and the vulcanizates may be used in hoses, rolls and gaskets.

Abstract: Compatibilized blends and composites of materials containing nitrile functionality with materials normally incompatible therewith are formed by mixing the components in the presence of an acid compatibilizing agent.

Abstract: This invention concerns a method of polymerizing high acrylonitrile resins in the presence of polymerized copolymers or terpolymers to produce thermoplastic products susceptible to molding and processing operations and having high impact strength and high heat distortion temperatures.

Abstract: Thermoplastic compositions are described comprising blends of styrene-acrylonitrile resin and nitrile rubber of high gel content.