Patent attributes
Mixtures comprising linear block copolymers composed of vinylaromatic monomers and dienes of the structure (I) S1-B1-S2 and (II) B2-S3, where S1 is a block composed of vinylaromatic monomers whose number-average molar mass Mn is in the range from 40 000 to 100 000 g/mol, each of S2 and S3 is a block composed of vinylaromatic monomers whose number-average molar mass Mn is in the range from 5000 to 20 000 g/mol, each of B1 and B2 is one or more blocks composed of dienes or is copolymer blocks composed of dienes and vinylaromatic monomers whose number-average molar mass Mn is in the range from 15 000 to 100 000 g/mol, and the ratio of block copolymers (I)/(II) is in the range from 0.5 to 10, and their use for impact-modification of blends using polystyrene.