Surface Characterization of Weathered Wood-Plastic Composites Produced from Modified Wood Flour
James S. Fabiyi, Armando G. McDonald, and Nicole M. Stark
The effects of weathering on the surface properties of wood-plastic composites (WPC) were examined. High-density polyethylene (HDPE) based WPCs made from modified wood flour (untreated, extractives free, and holocellulose (delignified) fibers) were subjected to accelerated (xenon-arc) weathering. Colorimetery and Fourier-transform infrared spectroscopy were employed to monitor the color change and surface chemistries of the weathered WPC surface. The compositional change that occurred on the WPC surface was determined using pyrolysis GC-MS analysis. The study showed that longer exposure time caused higher oxidation, lower wood lignin and higher plastic content of the weathered WPC surface. From this study, the use of holocellulose fibers improved the weathering performance (color) of WPCs.
