Transparent, impact-resistant, thermoplastic resin composition having excellent chemical resistance and process for producing same

摘要

A thermoplastic resin composition obtained by graft-polymerizing 95 to 50 parts by weight of a monomer mixture comprising a vinyl aromatic compound monomer and an acrylic compound monomer and optionally a vinyl cyanide compound monomer in the presence of 5 to 50 parts by weight of a rubbery substance consisting of styrene-butadiene copolymers, characterized in that the rubbery substance comprises (A) 40 to 80% by weight of a styrene-butadiene copolymer having a number-average particle diameter of at least 0.05 mu m and less than 0.2 mu m, a gel content of 30 to 100% by weight and a bound styrene content of 10 to 40% by weight and (B) 60 to 20% by weight of a styrene-butadiene copolymer having a number-average particle diameter of 0.2 to 3 mu m, a gel content of 10 to 80% by weight and a bound styrene content of 10 to 40% by weight and the total content of the components (A) and (B) in the rubbery substance is at least 80% by weight. Said thermoplastic resin composition is superior in chemical resistance, transparency, impact resistance and product appearance.