The Crystalline Superstructure of Polylactide (PLA) and PLA/ramie Fiber Bio-composites under Strong Shear Flow

摘要

The flow-induced shish-kebabs of polyolefins have been well demonstrated to be highly beneficial to mechanical strength,toughness,heat resistance,gas barrier,etc.However,it is still a challenge to achieve numerous shish-kebabs of biodegradable poly (L-lactic acid) (PLLA) due to its short chain length and semi-rigid chain backbone compared to polyolefins[1].In this work,a novel injection molding technology,named oscillation shear injection molding (OSIM),was applied to provide an intense shear flow on PLLA melt in cavity,in order to accelerate shear-induced crystallization of PLLA in injection molded PLLA and PLLA/ramie fiber bio-composites.