Nano-polytetrafluoroethylene regulated lightweight and high-strength wood fiber/polypropylene composite foams

Wood-plastic composite (WPC) is an environmentally friendly and cost-effective materials, while the high density and suboptimal mechanical properties of traditional WPC limit their broader applications.In this study, a wood fiber/ polypropylene composite foam (WPCF) is fabricated via chemical foaming enabled by Nano-polytetrafluoroethylene (PTFE).Compared with the unmodified wood fiber/polypropylene composite foam, our developed WPCF demonstrates a 37.69% increase in cell density and a 29.45% decrease in cell size with uniform cell distribution.The fine cell structure of WPCF is attributed to the improved crystallization and suitable viscoelastic behavior due to the addition of nano-PTFE.As a result, WPCF demonstrates superior mechnical performance.When the PTFE content was 1 wt%, WPCF shows a tensile strength of 9.41 MPa, a flexural strength of 22.63 MPa, and a improved impact strength of 5.27 kJ/m 2 , which is 47.65, 33.12, and 76.23% higher than those of unmodified WPCF.Given to the mechanical robustness and low density of WPCF, the as-prepared high-performance wood fiber/polypropylene composite foam is a promising alternative as a green and sustainable material to traditional wood in construction, furniture, and packaging sectors.