Influence of talc genesis on mechanical properties of polypropylene/talc composites

LUCIANA A. CASTILLO; SILVIA E. BARBOSA; NUMA J. CAPIATI

Gramado

Simposio; XII International Macromolecular Colloquium and 7th International Symposium on Natural Polymers and Composites; 2010

Universidade Federal do Rio Grande do Sul

The aim of this paper is to study the influence of talc genesis on mechanical properties of polypropylene (PP)/talc composites. For such purpose, two different kinds of composites were prepared by a single screw extruder, corresponding to different talc genesis: Australian and Argentinean ones, having different morphologies, but the same granulometry. The composites were prepared with 1, 3, 5 and 10 wt% of each talc. They were characterized by different techniques in order to elucidate their morphology, structure and thermal behavior. Dog bone tensile specimens were prepared by injection molding and mechanical properties were measured in an Instron tester. The elastic modulus was determined at low displacement rate with an extensometer and the other properties, like maximum tensile stress among others, were studied at higher rates, up to break. The results show that PP/Argentinean talc composite has better mechanical properties than PP/Australian talc one, especially elongation at break. This can be interpreted by means of induced morphology in the matrix by the talc according with their genesis.