Nano-TiO2 Modified Wheat Straw/Polylactic Acid Composites Based on Synergistic Effect Between Interfacial Bridging and Heterogeneous Nucleation

摘要

Abstract To improve the interfacial compatibility of wheat straw/polylactic acid (WS/PLA) composites, nano-TiO2 with different particle sizes was blended with molten PLA to modify straw fiber to obtain a nano-TiO2 modified WS/PLA composite. This study explored the effect of the nano-TiO2 particle size on the properties of the WS/PLA composites using mechanical property tests, contact angle measurements, water absorption tests, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The tensile strength and flexural strength of the modified composite improved to 44.9?MPa and 95?MPa, respectively. Mechanistic studies showed that nano-TiO2 played modified the interface and improved the interfacial compatibility of the composites by promoting the heterogeneous nucleation and rapid crystallization of PLA, which formed a stable crystal structure between the straw fiber and the PLA matrix. This study provides a method to develop biomass composites to solve environmental problems.Graphical Abstract