Effect of low/high hybrid of coffee husk powder on weathering resistance of WPCs composites

Abstract

In this study, wood-plastic composites (WPCs) were fabricated using a two-step melting process, blending high-density polyethylene (HDPE) with varying proportions of coffee shell powder (CHP) as a substitute for traditional wood powder. The weatherability of these composites was assessed through 2000 hours of exposure to xenon arc weathering. To evaluate the anti-aging properties of the WPCs, a range of tests were conducted, including infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), analysis of surface color, mechanical properties, thermal stability, and microstructure (SEM). The findings revealed that WPCs with a high hybrid CHP (HCHP/HDPE) composition experienced accelerated degradation after 2000 hours of weathering, leading to increased susceptibility to fading and cracking. In contrast, the O/C ratio of WPCs with a low hybrid CHP (LCHP/HDPE) composition increased minimally, recording values of 136.6% and 66.23% respectively, while their physical properties showed no significant decline. Therefore, it was concluded that low hybrid CHP fillers enhance the weather resistance of wood flour/HDPE composites.