Effect of talc on highly filled polypropylene composites containing post-consumer recycled polypropylene

Abstract

This study investigates the influence of talc content and post-consumer recycled polypropylene (rPP) on the properties of highly filled polypropylene composites. Composites containing 30 and 40 wt.% talc and varying proportions of virgin polypropylene and rPP were subjected to mechanical, thermal, microstructural, and processing characterization. The results showed that increasing talc content led to a significant improvement in composite stiffness, while the incorporation of rPP resulted in a deterioration of mechanical properties that could be partially compensated by the addition of the mineral filler. Differential scanning calorimetry (DSC) revealed only minor changes in melting and crystallization temperatures, whereas scanning electron microscopy (SEM) confirmed an increase in microstructural heterogeneity with increasing talc and rPP contents. Despite the high filler loading, all investigated materials exhibited satisfactory processing behavior. The results demonstrate that post-consumer recycled polypropylene can be successfully used in the production of highly filled PP/talc composites.