| abstract |
The invention relates to molding compositions containing styrene-acrylonitrile copolymers. As an essential ingredient, these contain 0.1 to 2.0% by weight, based on the copolymer, of a three-block polymer X-Y-X. X stands for the terminal ethylene oxide blocks and for a central propylene oxide block. The proportion of the terminal ethylene oxide blocks X, based on the block copolymer, should be 5 to 20% by weight, the middle propylene oxide block Y should make up 80 to 95% by weight and have an average molecular weight (number average) of 700 to 3,000. The molecular weight (number average) of the sum of the two terminal blocks X should be in the range from 140 to 1,000.n n n The claimed molding compositions are suitable for the production of moldings, since the three-block copolymers X-Y-X contained therein the processing properties of styrene-acrylonitrile copolymers, in particular the processing range in injection molding. influence advantageously without lowering the mechanical values of these copolymers. In this way, the failure rate of injection molded parts can be kept very low. |