| abstract |
Carboxylated styrene-diene block copolymers are produced by high yield radical grafting of 0.2 to 10 parts by mass beta -ethylenically unsaturated monocarboxylic and/or dicarboxylic acids or their anhydrides (carboxylic monomers), if required mixed with up to 10 parts by mass carboxyl-group free and anhydride-group free comonomers, with respect to 100 parts by mass of a block copolymer backbone, on non-hydrated and/or selectively hydrated styrene-diene block copolymers in a dry powdery, crumbly or granulated reaction phase at polymerisation temperatures from 40 to 100 DEG C. The functionalisation degree of the block copolymer can be accurately set in a range from 0.1 to 10 % graft polymerised carboxyl monomer, with respect to the available backbone mass. |