Graft copolymer, flame retardant composed of graft copolymer, and resin composition containing flame retardant

摘要

A copolymer that contains less amount of a residual volatile siloxane and has the excellent effects of improving flame retardancy and impact resistance is provided. A flame retardant composed of the copolymer, and a resin composition containing the flame retardant are also provided. The object can be accomplished by a polyorganosiloxane-containing graft copolymer prepared by polymerizing 0 to 10 parts by weight of a vinyl monomer (D) composed of 100 to 50 percent by weight of a polyfunctional monomer (B) containing at least two polymerizable unsaturated bonds and 0 to 50 percent by weight of another copolymerizable monomer (C) in the presence of 30 to 95 parts by weight of a polyorganosiloxane (A) in a latex form prepared by emulsion polymerization of a linear or branched siloxane having a terminal group selected from a hydroxyl group, an amino group, and a hydrolyzable group; and further polymerizing 5 to 70 parts by weight of a vinyl monomer (E) (the sum of (A), (D), and (E) being 100 parts by weight).