In situ fibrillation‐reinforced polypropylene‐based multi‐component foams

Abstract

AbstractRecent trends in energy and environmental protection have led to many studies of high‐performance microcellular foams. Polymer blends provide an effective way to improve foamability, microstructure, and performance versus single component thermoplastics. However, challenges remain for morphological control of polymer blends because the reinforcing effect depends upon the morphology of the dispersed phase. In this work, we present a feasible method for attaining microfibrils with high aspect ratios based on the in situ fibrillation of immiscible polymers to improve the morphology and distribution of the blend phase and improve the microcellular structure and mechanical properties of composite foams. Composite foams of polypropylene (PP)/thermoplastic polyester elastomer (TPEE)/polytetrafluoroethylene (PTFE) were fabricated, which were the polymer matrix, blend phase, and in situ fibrillation phase, respectively. The presence of PTFE and its effect on crystallization, rheology behavior, cellular structure, and mechanical properties were investigated. The results showed that PTFE microfibrils can promote melt strength, crystallization, and rheology properties. Thus, the multi‐composite foams achieve improved microcellular structure and mechanical properties, and improvements in these properties indicate the positive effects of an in situ fibrillation phase on the polymer blend foams.