Recycled Agricultural Waste Fiber-Reinforced Plastic Composites: Impact of Xenon Lamp Ageing on the System

Wood-plastic composites made from naturally recycled fibers and waste HDPE offer improved sustainability benefits. However, the utilization of agricultural waste as fiber filling in composite materials is uncommon. This paper presents the characterization of the ageing behavior of wood-plastic composites utilizing three types of recycled agricultural and forestry waste fibers (coffee shells, tobacco stems, and eucalyptus wood) as biofillers. The surface chemical properties of these samples were assessed using X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (FTIR) during accelerated xenon lamp aging at intervals of 0h, 500h, 1000h, 1500h, and 2000h. Results indicate that eucalyptus-wood/HDPE exhibits relatively superior resistance to photooxidative aging compared to other materials. Nonetheless, tobacco-stem/HDPE and coffee-shell/HDPE composites maintained elevated initial mechanical properties and demonstrated characteristics, including color change and storage modulus dissipation, comparable to those of eucalyptus-wood/HDPE. This implies their potential as cost-effective alternatives in the future.