Recycle polypropylene (RPP) wood saw dust (WSD) composites - Part 1: The effect of different filler size and filler loading on mechanical and water absorption properties

The compounding of recycled polypropylene (RPP) and wood saw dust (WSD) are carried out using five different filler loadings (0, 10, 20, 30, 40, and 50%) with three WSD filler sizes (100, 212, and 300 mu m). The composites are mixed and extruded using Haake Rheodrive 500 twin screw extruder. The mechanical and water absorption properties of composites are characterized accordingly. The results show that composites with a smaller particle size (100 mu m) have remarkably higher properties compared to others (212 and 300 mu m). Composites filled up to 30% WSD exhibits improved mechanical properties but the value dramatically decreased above 30% filler loading. The evidence of fiber-matrix interphase is analyzed using scanning electron microscope (SEM).