Recycling end-of-life WPC products into ultra-high-filled, high-performance wood fiber/polyethylene composites: a sustainable strategy for clean and cyclic processing in the WPC industry
Haiyang Zhou, Wenjuan Li, Xiaolong Hao, Guanggong Zong, Yi Xin, Junjie Xu, Rongxian Ou, Qingwen Wang
Abstract
As “green” composites, recycling end-of-life wood-plastic composites (WPCs) is crucial for sustainable and efficient resource utilization and carbon neutrality. In this study, waste WPC windows with 47.6 wt.% wood fiber (WF) were recycled as the polymer matrix and then reprocessed with waste WFs by extrusion into ultra-high-filled WF/polyethylene composites (UH-WPCs) using MAPE as a compatibilizer. The tensile and flexural moduli of all UH-WPCs with/without MAPE were higher than those of the waste WPCs. The MAPE-compatibilized UH-WPCs demonstrated improved water resistance, creep resistance, and dimensional stability. The tensile strength, tensile modulus, flexural strength, and flexural modulus of the UH-WPCs with 80 wt.% WF and 4 wt.% MAPE were 26.6%, 50.0%, 26.4%, and 87.9% higher than those of the waste WPCs, respectively. The presence of MAPE could improve the WF-matrix interfacial interaction and protect the WF from damage during reprocessing owing to the improved wettability and plasticization on WF. It is anticipated that the proposed strategy will provide a facile method to recycle end-of-life WPC products into high-performance composites at a low cost.