| abstract |
The graft copolymer made from n a1: from 10 to 90% by weight of a particulate graft base A1, made from a particulate emulsion polymer with a glass transition temperature below 0° C. made from n a11: from 70 to 100% by weight of butadiene or of at least one C 1-8 -alkyl acrylate, or of mixtures of these, as component A11, n a12: from 0 to 20% by weight of at least one polyfunctional crosslinking monomer, as component A12, n a13: from 0 to 30% by weight of other copolymerizable monomers, as component A13, the total amount of these being 100% by weight, n a2: from 10 to 90% by weight of a graft A2 made from the following monomers, the amounts being based on A2, n a21: from 60 to 100% by weight of at least one vinylaromatic monomer, or of a (meth)acrylic ester or of mixtures of these, as component A21, and n a22: from 0 to 40% by weight of at least one ethylenically unsaturated monomer, as component A22, n has a median particle diameter of from 130 to 500 nm and has polymodal particle size distribution in which less than 40% by weight of the particles are present in any particle size range of width 50 nm. |