The effect of talc orientation and transcrystallization on mechanical properties and thermal stability of the polypropylene/talc composites

The isotactic polypropylene/talc composites with talc stratified distribution were prepared by a multilayered co-extrusion technology. The talc orientation in polypropylene matrix was studied by scanning electronic microscopy and polarized light microscopy. The crystallization behavior of the composites was investigated by differential scanning calorimeter and polarized light microscopy. The mechanical properties and thermal stability of the composites were compared with the conventional blends by tensile machine and thermogravimetric analyzer, respectively. The composites with talc stratified distribution exhibited better mechanical properties and thermal stability than that of the conventional blends, which were related to the transcrystals in the unfilled polypropylene layers and the high orientation of talc particles in the filled polypropylene layers.