Efeito da incorporação de talco nas características térmicas, mecânicas e dinâmico-mecânicas de poliuretanos termoplásticos

Abstract

The aim of this work was to investigate the effect of adding talc, a nucleating agent widely used in general purpose thermoplastic formulations, on the crystallization behavior and the mechanical properties of two thermoplastic polyurethanes (TPUs) of different molecular weight. In this study, differential scanning calorimetry (DSC), thermogravimetry (TGA), dynamic-mechanical analysis (DMTA) and mechanical tests were employed. It was observed that the addition of talc increased the crystallization and the decomposition temperature of the highest average molecular weight TPU, although no change was observed at concentrations above 0.5 wt%. DMA analyses showed an increase in storage modulus only for the TPU with the highest average molecular weight. Mechanical testing did not show significant changes in the evaluated properties. The study demonstrated the importance of knowing the particular effects of adding talc as a nucleating agent in TPU compounds, aimed at improving their performance.