Effect of Wet-Dry Cycling on the Decay Properties of Aspen Fiber High-Density Polypropylene Composites

摘要

Aspen fiber-polypropylene composites were prepared with various levels of fiber (0, 30%, 40%, 50%, and 60%), polypropylene (PP) (100%, 98%, 70%, 68%, 60%, 58%, 50%, 48%, 40%, and 38%), and the compatibilizer maleated polypropylene (MAPP) (0 and 2%). Specimens were either subjected to 10 cycles of 1 week room temperature water soaking-oven drying or 2-hr, boiling water-oven drying. Thickness swelling and weight loss were calculated. Specimens were then exposed to the brown-rot fungus G.trabeum or the white-rot fungus C.versicolor for 12 weeks to determine the effect of repeated water cycling on decay. Results indicate that as the amount of aspen fiber increases there is an increase in weight and thickness swelling, as well as an increase in fungal attack after the water cycling tests. Presence of the compatibilizer seems to have an effect on the moisture weight gain, thickness swelling, and attack by fungi.