Patent ID: 6653374
Filing Date: 2003-11-25
Classification: C08F,C08K,C08L

Abstract:
A method of preparing a flameproof thermoplastic resin composition comprising:(A) a rubber modified styrene-containing resin composed of (a1) 20 to 100% by weight of a styrene-containing graft copolymer resin including 18 to 50% by weight of acrylonitrile in the copolymer excluding rubber; and (a2) 0 to 80% by weight of a styrene-containing copolymer resin containing 18 to 50% by weight of acrylonitrile; (B) polyphenylene ether resin; (C) a styrene-containing copolymer or a styrene-containing graft copolymer resin optionally containing rubber having 5 to 18% by weight of acrylonitrile in the copolymer excluding rubber component per 100 parts by weight of the sum of(A) and (B); and (D) an aromatic phosphoric acid ester flame retardant per 100 parts by weight of the sum of (A) and (B) wherein the method comprises: (i) preparing a master batch comprising 40 to 95 parts by weight of polyphenylene ether (B), 5 to 60 parts by weight of (C), and 0 to 30 parts by weight of aromatic phosphoric acid ester (D) at a molding temperature of 250 to 300Â° C.; and (ii) adding (A) and an aromatic phosphoric acid ester (D) to the master batch and extruding the mixture at a molding temperature of 200 to 260Â° C., wherein the amounts of (A) and (D) added in step (ii) result in a thermoplastic resin composition comprising 40 to 95 parts by weight of (A), 5 to 60 parts by weight of (B), 2 to 40 parts by weight of (C) per 100 parts by weight of the sum of (A) and (B), and 5 to 30 parts by weight of (D) per 100 parts by weight of the sum of (A) and (B).