Accelerated weathering performance of wood-plastic composites reinforced with carbon and glass fibre-woven fabrics

Abstract

Wood-plastic composites (WPCs) are new generation materials widely used in outdoor conditions; however, the appearance and mechanical properties of WPCs change with exposure to weather. In this study, high-density polyethylene-based flat-pressed WPCs are reinforced with carbon and glass fibre-woven fabrics for uses where high mechanical properties are needed in outdoor conditions. For this purpose, WPCs are exposed to accelerated weathering conditions to determine the effect of weathering with and without reinforcement. The results show that, after weathering, colour changes are inevitable for WPCs. Attenuated total reflection–Fourier transform-infrared analysis reveals the changes in the matrix's chemical structure, illustrating the alterations in WPC surface characteristics. The mechanical properties of WPCs decrease as a result of photodegradation. However, the reinforced WPCs have higher mechanical properties than the control samples, despite extensive degradation. Carbon fibre (200 g/m2) achieved the greatest flexural strength and modulus of elasticity, 150% and 122% higher, respectively, than unreinforced WPCs. Scanning electron microscopy analysis shows that, despite the intensive photodegradation on the surface, the integration of the matrix and woven fabrics was still strong. The surface erosion was observed with light microscopy. The visual appearance also exhibited some changes that occurred on the surface of WPCs