Patent ID: 6608141
Filing Date: 2003-08-19
Classification: C08F,C08J,C08L

Abstract:
A polymer composition comprising C8-12 vinyl aromatic polymer prepared by polymerization in the presence of from 0.01 to 0.1 weight % of a tetra functional peroxide initiator of the formula: wherein R1 is selected from the group consisting of C4-6 t-alkyl radicals and R is a neopentyl group, in the absence of a cross linking agent, comprising:i) from 60 to 100 weight % of one or more C8-12 vinyl aromatic monomers; and ii) from 0 to 40 weight % of one or more monomers selected from the group consisting of C1-4 alkyl esters of acrylic or methacrylic acid and acrylonitrile and methacrylonitrile; which polymer may be grafted onto or occluded within from 0 to 12 weight % of one or more rubbery polymers selected from the group consisting of: iii) co- and homopolymers of C4-5 conjugated diolefins; and iv) copolymers comprising from 60 to 85 weight % of one or more C4-5 conjugated diolefins and from 15 to 40 weight % of a monomer selected from the group consisting of acrylonitrile and methacrylonitrile, said vinyl aromatic polymer comprising about 10 to about 50 weight % of a star branched polymer.