IMPACT MODIFIER, PROCESS FOR PRODUCING THE SAME, AND THERMOPLASTIC RESIN COMPOSITION CONTAINING THE SAME

摘要

An impact modifier which comprises: an acrylic rubber type graft copolymer (I) obtained by graft-polymerizing a vinyl monomer (B) with a composite rubber (A) based on a polyalkyl (meth)acrylate; and either a compound (II) having a sulfonate group or sulfate group and one or more benzene ring skeletons or a salt of the compound (II). The composite rubber (A) comprises two or more acrylic rubber ingredients which differ in glass transition temperature and each contains up to 20 wt.% monomer having two or more unsaturated bonds per molecule. The compound (II) preferably has two or more benzene ring skeletons. The composite rubber (A) preferably has a particle size distribution having two or more peaks in a specific range. The impact modifier can impart improved impact resistance, especially low-temperature impact resistance, to a resin when used in a small amount. The resultant composition can give a molded article satisfactorily retaining color fastness, impact resistance, etc. in weathering.