Aging resistance under short time ultraviolet (UV) radiations of polymer wood composites entirely based on wastes

The paper studies the UV exposure influence on the mechanical properties, crystalline, interface and morphology of the optimised (previously water immersed) composites with wastes of rubber, PET, HDPE, wood and inorganic filler (CaO and fly ash). The mechanical strength, photo-degradation, crystalline structure and surface morphologies changes of the composites are evaluated after their exposure under simulated UV light and compared to unexposed ones. Experimental results showed UV exposure lead to the increase of Young moduli, compressive strength and tensile for high content PET samples. Significant mechanical strength even after water immersion and UV exposure were recorded for the rubber–PET–HDPE–wood–fly ash with a compression strength of about 70 MPa and for the 40 wt% PET composites with Young moduli of about 15 MPa. Therefore short term UV treatment could be used to enhance de composite’interface strength aiming at their outdoor applications.