Polypropylene Blends and Ethylene-octene Copolymer and Their Applications

Rheological، morphological and mechanical studies were performed on various blends of polypropylene (PP) and ethylene-octene copolymer (EOC). The oscillatory flow properties were determined at 220°C on a cone-plate rheometer (dynamic rheometer، SR 200) at an angular frequency range of 0. 01 to 100 rad/s. The rheological studies showed material flow behavior in the molten state. Scanning electron microscopy (SEM) revealed that as the amount of ethylene-octene copolymer increased، the size of elastomeric domains increased; and that dual-phase continuity occurred between 50 and 60 (wt%) of EOC. Studies on mechanical analysis showed that PP/EOC blends displayed higher impact strength than PP. With the addition ethylene-octene copolymer into polypropylene، the mechanical properties of the final blend improved because of lower elastic modulus intended for soft and flexible product and a low glass transition temperature to impart impact strength at low temperatures. This copolymer was compatible with PP in creating brightness and surface luster. The amount of long chain branches had significant effect on mechanical and rheological properties of ethylene-octene copolymer.