Crystallizability of Poly( ε -caprolactone) Blends with Poly(vinylphenol) under Different Conditions

The intermolecular interaction between poly(vinylphenol) (PVPh) and polycaprolactone (PCL) and the crystallization behavior of PCL in PCL/PVPh blends with different compositions and under different conditions were investigated by Fourier transform infrared spectra (FTIR) and differential scanning calorimetry (DSC). It has been shown that the PCL in the blends with different blend ratios all exists in crystalline state after solution casting, even though the crystallinity decreases with increasing PVPh content. For the melt crystallized samples, PCL in its 80/20 PCL/PVPh sample can still crystallize. The crystallinity is, however, lower than that of the solution cast sample. For blends containing 50% or 20% PCL, the as-cast samples are semicrystalline and can change to compatible amorphous state after heat treatment process. FTIR analysis shows the existence of hydrogen bonding between PCL and PVPh and the fraction of hydrogen bonds increases remarkably after heat treatment process.