Abstract: Disclosed is an ABS type polyblend composition exhibiting improved physical properties, which comprises from about 5 to 60% by weight of a copolymer of styrene and acrylonitrile; from about 10 to 70% by weight of a graft copolymer of styrene, acrylonitrile, and a butadiene polymer having an average rubber particle size of from about 1 to 10.mu.; and from about 10 to 70% of a high butadiene content backbone copolymer of styrene, acrylonitrile, and a butadiene polymer having an average rubber particle size of less than abut 0.5.mu., the ratios of the backbone copolymer and the styrene-acrylonitrile-butadiene polymer copolymer being adjusted such that from about 15 to 25% by weight of the total butadiene polymer content of the polyblend is provided by the larger rubber particle size graft copolymer.

Abstract: Disclosed is a process for the production of ABS resins comprising the steps of (a) imbibing a stabilized latex of a rubbery polymer with styrene in an amount of about 1.5 and 15 parts by weight per 100 parts of dry latex and with acrylonitrile in an amount of about 5 to 15 parts by weight per 100 parts of dry latex; (b) introducing the imbibed latex into a polymerization vessel; (c) introducing into the polymerization vessel a mixture of styrene, acrylonitrile and a free radical initiator; (d) introducing a polymerization activator into the polymerization vessel; (e) polymerization the styrene and acrylonitrile in the polymerization vessel in the presence of the latex, whereby an ABS graft copolymer is produced; and (f) withdrawing the ABS polymer from the polymerization vessel.

Abstract: A process for producing a copolymer of styrene and acrylonitrile substantially free of acrylonitrile which comprises copolymerizing styrene and acrylonitrile, and optionally in the presence of an elastomer, and treating the resulting copolymer with an aqueous solution of a sulphur compound selected from the group consisting of alkaline sulfides and alkaline disulfides.

Abstract: A process for producing a copolymer of styrene and acrylonitrile substantially free of acrylonitrile which comprises copolymerizing styrene and acrylonitrile and treating the resulting copolymer with an aqeuous solution of a sulphur compound selected from the group consisting of alkaline sulfides and alkaline disulfides.