COMPOSITION DE RESINE RESISTANT A LA CHALEUR ET AUX CHOCS

A heat and impact resistant resin composition which comprises from 10 to 90 parts by weight of a copolymer (A) comprising from 90 to 50% of residues of a vinyl aromatic compound, from 10 to 50% of residues of a maleimide compound and from 0 to 30% of residues of a vinyl compound copolymerizable therewith; from 0 to 50 parts by weight a copolymer (B) comprising from 90 to 40% of residues of a vinyl aromatic compound and from 10 to 60% of residues of an unsaturated nitrile compound; from 5 to 89 parts by weight of a graft copolymer (C) comprising from 25 to 70% by weight of particles of a rubber having a glass transition temperature of not higher than 0 DEG C. and an average particle size of from 0.1 to 0.5 mu m and from 75 to 30% by weight of a matrix resin comprising from 90 to 40% of residues of a vinyl aromatic compound and from 10 to 60% of residues of an unsaturated nitrile compound; and from 1 to 45 parts by weight of a graft copolymer (D) comprising from 2 to 17% by weight of particles of a rubber having a glass transition temperature of not higher than 0 DEG C. and an average particle size of from 0.7 to 4 mu m and from 98 to 83% by weight of a matrix resin comprising from 90 to 40% of residues of a vinyl aromatic compound and from 10 to 60% of residues of an unsaturated nitrile compound, wherein the amount of the graft copolymer (C) is from 97 to 50% by weight of the total amounts of the graft copolymers (C) and (D).