Impact modifier and thermoplastic resin composition using the same

摘要

An impact modifier comprising a blend of 100 parts by weight of a multi-layer graft copolymer composed of monomers selected from the group consisting of alkyl acrylates, alkyl methacrylates, aromatic vinyl compounds, vinyl cyanide compounds and butadienes and having a multi-layer structure consisting of at least three layers (A), (B) and (C) in which the glass transition temperature of the polymer composing the outermost layer (A) is 0 DEG C. or below, the glass transition temperature of the polymer composing the second layer (B) from the outermost layer (A) is 60 DEG C. or above and the glass transition temperature of the polymer composing the third layer (C) from the outermost layer (A) is 0 DEG C. or below, each of the layers containing a polyfunctional crosslinking agent in an amount of 0 to 5% by weight based on the weight of the layer, and 0.1 to 20 parts by weight of a copolymer obtained by copolymerizing 3 to 30% by weight of an unsaturated acid monomer and 97 to 70% by weight of a vinyl monomer copolymerizable therewith, and a thermoplastic resin composition having excellent impact resistance and molding workability comprising 3 to 50 parts by weight of the modifier set forth above and 100 parts by weight of a thermoplastic resin.