PHASE-BEHAVIOR OF POLY(EPSILON-CAPROLACTONE)/POLY(VINYLIDENE FLUORIDE) BLENDS

The miscibility of blends of poly(epsilon-caprolactone) (PCL)/poly(vinylidene fluoride) (PVDF) was studied by measuring the cloud point, melting point depression and crystallization kinetics. Lower critical solution temperature (LCST) behavior was observed at PCL-rich compositions, whilst it was not observed at high compositions of PVDF. However it is possible that an LCST could exist below the melting point of PVDF. From analysis of the melting point depression, the Flory interaction parameter x12 was calculated from the Nishi-Wang equation and the value was found to be - 1.5. The crystallization rate of PCL increased with increasing amount of PVDF in the blend. The spinodal curve for PCL/PVDF blends was simulated by using the lattice-fluid theory.