Effects of Combined Elastomers on Impact Properties and Morphology of PP/Elastomer/CaCO₃ Ternary Composites

Abstract

The influences of combined elastomers on impact properties and morphology of polypropylene (PP)/elastomer/CaCO₃ ternary composites were investigated. When polystyrene-block-poly(ethylene-butene)-block-polystyrene triblock copolymer (SEBS) and poly(ethylene-octene) copolymer (EOR) were used as elastomer, the core-shell elastomer particles with EOR-core and SEBS-shell were formed. The elastomer particles and CaCO₃ particles were separately dispersed in PP matrix. When carboxylated SEBS (C-SEBS) combined with EOR were used as elastomer, the C-SEBS particles were dispersed in EOR particles. CaCO₃ particles were dispersed in PP matrix, whereas a part of the CaCO₃ particles were dispersed in C-SEBS/EOR combined particles. Impact strength increased with the amount of incorporated CaCO₃ particles. The effect of elastomer on the impact strength was SEBS ≥ SEBS/EOR > EOR = C-SEBS/EOR > C-SEBS. The morphology formed by elastomer and CaCO₃ particles strongly affected the impact properties of the ternary composites.