Desenvolvimento e caracterização de misturas de polipropileno com teores variáveis de resina pós-consumo (PCR)

Abstract

The rise in plastic waste generation has driven research into developing polymeric materials that incorporate recycled feedstocks without compromising technical performance. In this context, this study aimed to develop and characterize polypropylene blends containing varying levels of post-consumer recycled (PCR) resin, seeking to establish correlations between blend composition and physical properties. Five formulations with different proportions of virgin and recycled polypropylene were prepared for the study. The materials were processed via injection molding—producing five specimens per formulation for tensile testing and five for Charpy impact testing—and subsequently characterized through rheological and mechanical tests. Rheological properties were evaluated using the melt flow index (MFI), while mechanical properties were assessed through tensile strength and Charpy impact tests. The results indicated that the incorporation of recycled polypropylene directly influences the rheological and mechanical behavior of the blends. It was observed that increasing the virgin polypropylene fraction enhanced melt flow and tensile strength, whereas the recycled polypropylene demonstrated superior impact energy absorption. Mean values ranged from 3.63 to 35.08 g/10 min for MFI, 21.19 to 30.34 MPa for tensile strength, and 7.59 to 10.59 kJ/m² for Charpy impact strength, highlighting the influence of composition on blend properties. Intermediate formulations showed a balance between mechanical performance and recycled material content, demonstrating the potential for using these blends in industrial applications that aim to reconcile technical performance with sustainability.