Particulate graft polymer with improved adhesion between grafting base and graft sheath

摘要

A particulate graft polymer comprises from 30 to 90% by weight, of at least one elastomeric polymer A having a median particle size of from 30 to 1000 nm comprising--based on A--from 85 to 99.8% by weight of at least one alkyl acrylate A1 having from 1 to 8 carbon atoms in the alkyl moiety, from 0.1 to 5% by weight of at least one polyfunctional, crosslinking monomer A2 and from 0.1 to 10% by weight of at least one further monoethylenically unsaturated monomer as grafting base, and from 10 to 70% by weight, grafted onto the elastomeric polymer A, of a sheath B comprising--based on B--from 50 to 90% by weight of at least one aromatic vinyl monomer B1 and from 10 to 50% by weight of at least one polar, copolymerizable, ethylenically unsaturated monomer B2, wherein monomer A3 is a hydroxyalkyl acrylate or methacrylate.