Effect of small amount of multi-walled carbon nanotubes on crystallization and thermal-mechanical properties of overflow microinjection molded isotactic polypropylene

Abstract

Herein, the solution-melt blended multi-walled carbon nanotubes (MWCNTs)/isotactic polypropylene composites are molded by an overflow microinjection molding. All parts exhibit the highly oriented structures, and the number of oriented shish-kebab structures progressively increase with increasing MWCNTs content. More importantly, small amount of MWCNTs (i.e., 0.1 wt%) can significantly improves crystallization rate and crystallinity of all composite parts, nevertheless, the formation of β-crystal is remarkably suppressed. Moreover, compared with the pure part, tensile modulus, toughness and thermostability of composite parts are mildly enhanced. This work provides a facile method to fabricate high-performance composite parts via overflow microinjection molding, which would lay a foundation for optimizing the macroscopic performances of polymer-based composites.