Weather resistant impact modifiers for thermoplastic resins

摘要

A weather resistant impact modifier for thermoplastic resins and a blend with the thermoplastic resin are disclosed. The modifier comprises a graft copolymer having a multi-layered structure which is obtained by graft polymerization of (c) 10-100 parts by weight of an aromatic vinyl compound or a monomer mixture mainly composed of an aromatic vinyl compound in a first stage and 10-100 parts by weight of a methacrylic ester or a monomer mixture mainly composed of a methacrylic ester in a second stage, (b) to 100 parts by weight of an elastomer obtained by polymerizing 98-60 parts by weight of a monomer mixture composed of 50-99.95% by weight of an acrylic ester, 0-50 wt % of a copolymerizable monomer and 0.05-5% by weight of a polyfunctional monomer, (a) in the presence of 2-40 parts by weight of a butadiene elastomer having a degree of swelling of 5-40 and an average particle size of not smaller than 0.15 (my)m (wherein the total of (a) and (b) is 100 parts by weight).