Effect of Chemical Modification on Mechanical Properties of Wood-Plastic Composite Injection-Molded Parts

Polymers (Basel). 2018 Dec 15;10(12):1391. doi: 10.3390/polym10121391.

Abstract

Wood chips from furniture-manufacturing byproducts, which do not include adhesive or paint in the waste wood, were used for the flouring process and chemical modification of wood flour (WF). After chemical modification, the WF was mixed with polypropylene through extrusion compounding and injection-molding to prepare wood-plastic composite (WPC) injection-molded specimens for the American Society for Testing and Materials. Static contact angle measurements and stereomicroscope observations were performed. In this study, it was confirmed that the impact strength was improved by up to 55.8% and the tensile strength by up to 33.8%. The flexural modulus decreased marginally. As a result of WF chemical modification, the measured contact angle of WPC increased, which means that the wettability of the WPC specimen surface decreased. In addition, it was observed through stereomicroscopy that the whitening of the surface of the WPC specimen improved.

Keywords: chemical modification; co-rotating intermeshing twin-screw extrusion; composite pellet; injection molding; wood-plastic composite.