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

摘要

A rubbery graft copolymer is provided to reduce the content of metal ions present in an emulsifier and coagulating agent remaining in the copolymer, and to obtain a thermoplastic resin composition having improved flowability, whiteness and impact strength. A rubbery graft copolymer is obtained by a method comprising the steps of: (a) polymerizing a rubbery polymer, an aromatic vinyl monomer and a vinyl cyanide monomer to provide a graft copolymer latex; (b) adding an acidic aqueous solution coagulating agent to the graft copolymer latex to perform coagulation; (c) adding an aqueous basic solution to the coagulated latex to adjust the pH; and (d) dewatering, washing and drying the pH-adjusted latex.