Evaluation of the effect of processing conditions on the impact properties of polypropylene-nano-CaCO3 composites

Abstract

Processing variables are known to have a decisive influence on the impact properties of polypopylene-nano-CaCO3 composites. Therefore, it becomes mandatory to evaluate the effect of extrusion conditions on composite impact resistance. In the present work, a response surface methodology was used to evaluate the effects of screw rotation speed, screw configuration, and nanoparticles content on the polypropylene impact properties. The concentration of the nano-CaCO3 particles, the screw rotation speed, and the interaction between these entrance factors were the processing variables of greater influence on the impact properties of nano-CaCO3/polypropylene composites. The increase of screw rotation speed led to a decrease in the impact resistance, while the increase of filler content promoted an increase of such property. However, the increase of nanoparticles content led to obtaining poor tensile properties. Therefore, the filler content has to be adjusted in order to improve the impact properties without significant loss of mechanical strength.