COMPATIBILIZATION OF LOW-DENSITY POLYETHYLENE POLYSTYRENE BLENDS BY SEGMENTED EB(PS-BLOCK-EB)(N) BLOCK-COPOLYMERS/

Hydrogenated segmented poly[butadiene-block-(styrene-block-butadiene)( n)] block copolymers, which were developed by use of a polymeric inife rter technique, were tested on their compatibilizing effectiveness for (10/90) LDPE/PS blends. They were found to be effective compatibilize rs for this mixture, already giving a pronounced improvement in both t ensile strength and strain of the blend at block copolymer concentrati ons of one percent. A concentration of five weight percent of segmente d block copolymer provided a tenfold improvement in blend toughness. T he effectiveness of the segmented block copolymers was found be depend ent on the block copolymer composition. Block copolymer compositions o f close to 50:50 EB:PS gave the best results.