INFLUENCING THE MORPHOLOGY OF POLYMER BLENDS THROUGH GRAFT-COPOLYMERS

Graft copolymers have a potential as compatibilizers in two-component thermoplastic polymer blends, and also as impact-modifiers in one-comp onent thermoplastics. The compatibility of the blocks of the copolymer (i.e. the grafts and the main chain) with the chains of the matrix po lymers must be adjusted carefully. Blends of various polymers, especia lly of polystyrene (PS) and poly(vinyl chloride) (PVC), with graft cop olymers on the basis of polybutadiene are discussed. An excellent comp atibilizer, for blends PS/PVC, is a block-graft copolymer, derived fro m a diblock copolymer of styrene and butadiene, with grafts of cyclohe xyl methacrylate monomeric units.