STUDY ON THE POLYPROPYLENE/HIGH DENSITY POLYETHYLENE/STYRENE-BUTADIENE-STYRENE BLOCK COPOLYMER TERNARY BLENDS .1. COMPOSITION, MORPHOLOGY AND PROPERTIES OF POLYPROPYLENE HIGH DENSITY POLYETHYLENE/STYRENE-BUTADIENE-STYRENE BLOCK COPOLYMER BLENDS

摘要

Thermoplastic elastomers, e.g., EPR, EPDM etc., are commonly used as modifiers of the ductility of PP, PE, HDPE or other general purpose thermoplastics. The objective of this study is to develop a high performance PP/HDPE/SBS polymer blend which possesses excellent toughness and strength equivalent to those of more expensive high-grade engineering plastics and to investigate the change of ratio of PP, HDPE and SBS with morphology and mechanical properties of the blend. It was found that the introduction of HDPE into the mixture of PP/SBS gives rise ternary blends possessing not only super high ductility and impact strength (over 700 J/m), but also balanced mechanical properties (high tensile strength and flexural strength), as well as excellent thermal resistance and processing properties. It was also found that the morphology of the PP/HDPE/SBS ternary blends is a multiphase system. It appears that the resulted complex morphology renders the high performance of the ternary blends. [References: 9]