Clean and sustainable biocomposites based on supramolecular interactions induced thermoplasticization of wheat straw powders

Abstract

Plenty of biomass resources like wheat straw (WS) have been burnt in farmland, resulting in severe resource waste and environment pollution. It is still a big challenge to directly convert crop straws into clean products by thermoplastic processing methods due to their none thermal meltability. Herein, clean and sustainable WS-based biocomposites (SWTPs) with fascinating thermal meltability, mechanical property, and dimensional stability after water absorption have been for the first time prepared by novel supramolecular interactions induced thermoplasticization technique under solvent-free condition, wherein supramolecular interactions stands for that the initial hydrogen bondings of WS have been effectively replaced by new interactions between chlorine atoms of the developed supramolecular inducer and hydroxyl groups of WS. Microstructure, thermoplastic behavior, thermal stability, morphology, and related thermoplascitization mechanism of the SWTPs have been extensively assessed. Relevant results reveal that the initial intense hydrogen bondings of WS can be significantly reduced resulting from the newly formed supramolecular interactions between WS powders and the used supramolecular inducers. The obtained SWTPs show outstanding thermal meltability in the temperature range of 130–180 °C and excellent thermal stability in the temperature range of 25–240 °C. Industrialization value and economy value of the produced biocomposites have been briefly discussed. The developed SWTP productions show large potential application in replacing unsustainable and eco-unfriendly petroleum based polymers.