GRAFT COPOLYMER, METHOD FOR PREPARING THE SAME AND THERMOPLASTIC RESIN COMPOSITION CONTAINING THE SAME

摘要

A graft copolymer, a method for preparing the graft copolymer, and a thermoplastic resin composition containing the graft copolymer are provided to improve impact resistance, coloring property, stiffness, heat resistance and weather resistance. A graft copolymer comprises 20-80 parts by weight of an alkyl acrylate rubber polymer comprising an alkyl acrylate rubber polymer having an average diameter of 300-600 nm and an alkyl acrylate rubber polymer having an average diameter of 20-200 nm; and 20-80 parts by weight of at least one monomer selected from an aromatic vinyl compound, a vinyl cyano compound and an alkyl (meth)acrylate compound, wherein the alkyl acrylate rubber polymer is prepared by polymerizing 1-10 parts by weight of at least one monomer selected from an aromatic vinyl compound, a vinyl cyano compound and an alkyl (meth)acrylate compound to prepare a seed having a large particle size; polymerizing 5-70 parts by weight of an alkyl acrylate in the presence of the prepared seed to prepare an alkyl acrylate rubber polymer having an average diameter of 250-550 nm; polymerizing 1-10 parts by weight of at least one monomer selected from an aromatic vinyl compound, a vinyl cyano compound and an alkyl (meth)acrylate compound in the presence of the prepared alkyl acrylate rubber polymer to prepare a mixture of the alkyl acrylate having a large particle size and a seed having a small particle size; and polymerizing 5-70 parts by weight of an alkyl acrylate monomer in the presence of the mixture.