Morphology of polyvinylidene fluoride and its blend in thermally induced phase separation process

Polyvinylidene fluoride (PVDF) and its blend films were prepared by melt-blending the binary mixture of PVDF/dibutyl phthalate (DBP) and the ternary mixture of PVDF/CaCO3/DBP in combination of TIPS. Their morphologies were characterized by scanning electron microscope depended on preparation condition, such as the diluent and CaCO3 weight fraction, and the cooling rate, and the crystallization information was also investigated by DSC. The results showed that CaCO3 influenced the morphology of PVDF in the TIPS process regardless of the cooling conditions, and the formation of the spherulitic morphology can be disturbed by CaCO3 at the quenching condition. The effect of CaCO3 weight fraction on the tensile strength of PVDF was measured, which indicated CaCO3 had a negative effect on PVDF tensile strength. (c) 2006 Wiley Periodicals, Inc.