Torque rheological properties of polypropylene/cocoa pod husk composites

Abstract

The torque rheological properties of plastic wood composites are important to practical processing, but the research in this field is rare. In present, a Brabender plastrograph torque rheometer was used to analyse the rheological behavior of polypropylene (PP)/cocoa pod husk (CPH) composites. The effect of processing parameter, filler content, and addition of maleated polypropylene (MAPP) on torque rheological properties was investigated. The torque rheological data found that the processing torque increased with the increases of rotor speed, filler content, and addition of MAPP. The PP/CPH composites melt behavior as pseudoplastics and shear thinning occurred at higher shear rate. The decrease of power law index ( n) evidenced the pseudoplasticity of PP/CPH composites increased at higher filler content and presence of MAPP. The increase of viscosity on PP/CPH was due to filler–filler interaction at higher filler content and strong filler–matrix adhesion after addition of MAPP. The activation energy of PP/CPH composites also increased with higher amount of CPH and addition of MAPP.