COMPORTAMENTO MECÂNICO E TÉRMICO DE MISTURAS DE POLIPROPILENO VIRGEM E REPROCESSADO POR MÚLTIPLAS EXTRUSÕES

Abstract

It is well known the wide use of polymeric materials and the proportional negative impact especially polymers "commodity" (PP, PE, PVC, PET, etc.) because when discarded in the environment. This has worried the scientists, which increasingly develop technologies for the reuse that’s materials. The market for recycling ther moplastic polymers currently lies in sharp rise. The materials are seen as inferior material properties compared to virgin material. It was found in this study that the reuse of the polypropylene (PP H301) repeatedly reprocessed by extrusion when mixed with virgin resin of the same polymer at different rates, will not negatively affect the mechanical and thermal properties this polymer. In traction system when compared to virgin polypropylene, there was an increase of 4% in yield stress,3% in maximum stress and 31% in the breakdown stress. Likewise it occurred in bending system, with gains of 7% and 5% for the modulus of elasticity and maximum stress, respectively. Thermal properties did not suffer negative effects with multiple reprocess and with the addition of reprocessed polypropylene, with values similar to virgin polypropylene. A reduction of 12% in the degree of crystallinity of the samples was observed. In general, the addition of polypropylene reprocessed to virgin polypropylene is presented as a great alternative to the process industries,with advantages in economic and environmental spheres.