Patent ID: 6716917
Filing Date: 2004-04-06
Classification: C08L

Abstract:
A method of producing a rubber-reinforced styrene transparent resin composition, which is a styrene copolymer reinforced with a rubber polymer, and has an acetone soluble resin component having a monomer composition comprising 5to 70% by weight of aromatic vinyl monomer, 30 to 95% by weight of unsaturated carboxylic acid alkyl ester monomer, 0 to 50% by weight of vinyl cyanide monomer, and 0 to 50% by weight of another monomer copolymerizable with these monomers, the acid value of the acetone soluble resin component being 0.01 to 1 mgKOH/g, the method comprising:continuously bulk polymerizing or continuously solution polymerizing a vinyl monomer mixture (a) to obtain a copolymer (A); removing residual monomer from the copolymer (A) following the continuous bulk polymerization or the continuous solution polymerization of the vinyl monomer mixture (a); during or after the step of removing the residual monomer from the copolymer (A), adding 90 to 5 parts by weight of a graft copolymer (B) to 10 to 95 parts by weight of a copolymer (A) in a melt state and melt-blending the graft copolymer (B) and copolymer (A), said graft copolymer (B) being obtained by graft-polymerizing a vinyl monomer mixture (c) in the presence of a rubber polymer (b) and having a moisture content of 0.1% or more by weight and less than 5% by weight, the vinyl monomer mixtures (a) and (c) each being independently a monomer mixture comprising 5 to 70% by weight of (a1) aromatic vinyl monomer, 30 to 95% by weight of (a2) unsaturated carboxylic acid alkyl ester monomer, 0 to 50% by weight of (a3) vinyl cyanide monomer, and 0 to 50% by weight of (a4) another monomer copolymerizable with these monomers, and containing (a5) substantially no unsaturated carboxylic acid monomer other than the unsaturated carboxylic acid alkyl ester monomer (a2), and the graft copolymer (B) containing 0.1 to 5% by weight of an emulsifier.