Patent ID: 7074854

Claim:
Polymer compositions containing I) a graft rubber polymer that is obtained by emulsion polymerisation of styrene and acrylonitrile in a weight ratio of 95:5 to 50:50, wherein styrene and/or acrylonitrile can be wholly or partially replaced by Î±-methyistyrene, methyl methacrylate or N-phenylmaleimide or mixtures thereof, in the presence of a mixture of a butadiene polymer latex (A) with a mean particle diameter d 50 â‰¦250 nm and a particle size distribution width (measured as d 90 â€“d 10 from the integral particle size distribution) of 20 to 80 nm and a gel content of 30 to 95 wt. %, a butadiene polymer latex (B) with a mean particle diameter d 50 >250 to 350 nm, a particle size distribution width (measured as d 90 â€“d 10 from the integral particle size distribution) of 30 to 100 nm and a gel content of 30 to 80 wt. %, and a butadiene polymer latex (C) with a mean particle diameter d 50 >350 nm, a particle size distribution width (measured as d 90 â€“d 10 from the integral particle size distribution) of 40 to 150 nm, and a gel content of 50 to 95 wt %, wherein the butadiene polymer latices in each case contain 0 to 50 wt. % of a further vinyl monomer incorporated by copolymerisation and wherein the mass ratio of the graft monomers that are used to the butadiene polymers that are used is 5:95 to 70:30, and II) at least one rubber-free copolymer of styrene and acrylonitrile in a weight ratio of 95:5 to 50:50, wherein styrene and/or acrylonitrile can be wholly or partially replaced by Î±-methylstyrene, methyl methacrylate or N-phenylmaleimide or mixtures thereof, wherein at least one latex selected from the butadiene polymer latices (A), (B) and (C) is produced by seed polymerisation.