Abstract: A vinyl chloride resin composition having surface smoothness comprises:(1) 100 parts of vinyl chloride polymer; and(2) 0.1 to 30 parts of a polymer processing aid comprising:(A) 10 to 100 parts of a copolymer comprising 20 to 99% of an alkyl methacrylate, 1 to 70% of a dialkyl itaconate, and 0 to 60% of a monomer copolymerizable therewith; and(B) 0 to 90 parts of a copolymer comprising 80 to 100% of an alkyl methacrylate, and 0 to 20% of a monomer copolymerizable therewith,the sum of the quantities of the copolymers (A) and (B) producing 100 parts of the polymer processing aid, all quantities expressed in parts and percentages being by weight.This vinyl chloride resin composition comprising a novel polymer processing aid not only shows an increased gelation rate, yields less ungelled particles and possesses excellent processability such as an increased elongation at a high temperature, but particularly affords a formed product of notably improved surface smoothness.

Abstract: A thermoplastic resin composition of excellent transparency and high impact strength is produced by causing methyl methacrylate and styrene monomers to undergo post polymerization in the presence of a conjugated diolefin polymer rubber latex containing at least 50 percent by weight of a conjugated diolefin monomer as the constituent of the rubber such as butadiene, wherein a polyethylene oxide of an average molecular weight of at least 100,000 has been added to the rubber latex either prior to or at the time of the post polymerization to cause the rubber latex to partly coagulate, thereby to prepare a graft polymer. The graft copolymer can be blended with methyl methacrylate-styrene copolymers.

Abstract: A photo-degradable synthetic resin composition which consists of a blend of a butadiene-containing graft copolymer and a thermoplastic resin. The blend consists essentially of (A) 50-99 parts by weight of a graft copolymer containing at least 30% by weight of butadiene monomer, said copolymer being composed of 40-80 parts by weight of butadiene or a copolymer thereof, 60-20 parts by weight of styrene, methyl methacrylate or a mixture thereof and 0.01-5 parts by weight of a cross-linking agent copolymerizable therewith, and (B) 1-50 parts by weight of polystyrene, polymethyl methacrylate, polyacrylonitrile, polyvinyl chloride, polyvinylidene chloride or copolymers thereof.