The effects of quenching on the phase structure of vinylidene fluoride segments in PVDF-HFP copolymer and PVDF-HFP/PMMA blends

The phase characteristics of vinylidene fluoride (VDF) segments in vinylidene fluoride (VDF) and hexafluoropropylene (HFP) copolymer (PVDF-HFP) under different quenching temperature were investigated by infrared spectroscopy (FTIR) and X-ray diffraction (XRD) measurements. It was found that the α and β crystalline phases of VDF segments formed in PVDF-HFP as those in pure PVDF. Compared with pure PVDF, HFP segments affected the β phase formation obviously. Increasing of quenching temperature would decrease the fraction of β phase in the quenched PVDF-HFP films, and the films thicker than 8 μm were not in favor of the β phase transformation. Blending PVDF-HFP with small amounts of PMMA (≤10 wt%) yielded great effects on the crystal phase of VDF segments. But higher blending degree of PMMA couldn’t increase the formation of β phase further. C 2006 Springer Science + Business Media, Inc.