Process Rheology and Mechanical Property Correlationship of Wood Flour-Polypropylene Composites

Abstract

The rheological properties of wood fiber reinforced thermoplastics blends are important to practical industry application, however few research is available regarding this field. In this study, a C. W. Brabender Plasti-Corder torque rheometer was used to examine the flow behavior of wood flour filled polypropylene (PP) composites. The effect of loading level of wood flour and an internal lubricant on the rheological properties was studied. The results show that the wood flour-PP blends behavior as pseudo-plastics or shear-thinning flow under the experimental conditions investigated. The addition of internal lubricant is effective in reducing the apparent viscosity that tends to increase with a higher loading of wood flour. The effect of shear rate on the efficiency of internal lubricant was also investigated. For practical application, it is recommended to use both internal lubricant and phase compatibilizer such as Maleic Anhydride grafted polypropylene (MAgPP), thus improving the processing operation while maintaining the strength properties of the wood flour-PP composites.