Abstract: Polypropylene/wood flour composites (WPC) were prepared via injection molding, containing carbon black, titanium dioxide, and iron oxide as pigments. Effect of the pigments on aging property of WPC was studied through thermal-oxidative aging in oven and xenon lamp aging. It showed that with increasing aging time of WPC, the tensile strength and oxidation induction time decreased, and melt flow rate and color change increased with or without pigments. Before and after aging in the oven, the tensile strength, oxidation induction time and color change was lower for the WPC with titanium dioxide or iron oxide as pigment, and the melt flow rate of WPC was larger. In xenon lamp aging condition, the change speeds of tensile strength, melt flow rate, color and oxidation induction time of WPC with the pigments was lower than that of WPC without the pigments.

Key words: polypropylene, pigment, aging property, wood flour, composite