Thermoplastic resin composition having excellent impact resistance and heat resistance

摘要

A thermoplastic resin composition having excellent impact resistance and heat resistance which comprises 5 to 95% by weight of a graft copolymer (I) obtained by polymerizing 93 to 30 parts by weight of a monomer or a monomer mixture for grafting comprising 30 to 100% by weight of at least one monomer selected from the group consisting of styrene, alpha -methylstyrene, acrylonitrile and methyl methacrylate and 0 to 70% by weight of at least one copolymerizable monomer having CH2=C< group in the presence of 7 to 70 parts by weight (in terms of solid) of a rubber latex of agglomerated particles having a particle diameter of at least 0.2 mu m obtained by adding 0.1 to 5 parts by weight (in terms of solid) of an acid-group containing copolymer (B) latex obtained from 3 to 30% by weight of an acid-group containing monomer, 97 to 35% by weight of at least one alkyl acrylate having 1 to 12 carbon atoms in the alkyl group, and 0 to 48% by weight of at least one monovinyl monomer copolymerizable therewith (100% by weight in total) to 100 parts by weight (in terms of solid) of a rubber (A) latex of small particle size having a pH of 7 or above obtained from 100 to 50% by weight of 1,3-butadiene and 0 to 50% by weight of other copolymerizable monomer having CH2=C< group (100% by weight in total); 95 to 5% by weight of a thermoplastic resin (II) obtained by polymerizing alpha -methylstyrene and at least one other copolymerizable monomer having CH2=C< group; and 0 to 50% by weight of other thermoplastic resin (III) containing no alpha -methylstyrene unit, said components (I), (II) and (III) being compounded so as to give a content of said butadiene rubber (A) in the whole composition of 3 to 40% by weight and a content of alpha -methylstyrene unit in the whole composition of 10 to 75% by weight.