Influence of talc morphology on the mechanical properties of talc filled polypropylene

摘要

Injected polypropylene (PP)/talc composites were studied to evaluate the influence of different talc morphologies on their final mechanical properties. Talc genesis is responsible for type and content of associated minerals, crystalline degree, particle size distribution, and specially, morphology. Consequently, when talc is incorporated into PP, differences in the genesis mean differences in particle morphology and may influence the composite properties. Two talc samples having predominant macro and microcrystalline morphologies were used to prepare two composite sets to be tested. Thermal and mechanical properties of each PP/talc composites set were measured, analyzed and discussed comparatively. The results reveal that the main influences of talc morphology are given on modulus, yield strength and elongation at break of PP/talc composites. Macrocrystalline morphology of talc induces better composite mechanical properties than microcrystalline one. This behavior could be explained by talc characteristics as lamellarity, crystalline character and crystallinity degree.