Structure formation and electrophysical properties of poly(vinylidene fluoride-hexafluoropropylene) copolymer films at low-temperature solution crystallization

The structural and electrophysical characteristics of poly (vinylidene fluoride-hexafluoropropylene) copolymer films with hexafluoropropylene content 8.3 mol%, obtained by low-temperature crystallization from various solvents, have been investigated. X-ray diffraction data indicate that the films crystallized mainly in the α-phase. When acetone is used as a solvent, the degree of crystallinity is the lowest due to the rapid escape of solvent molecules from solution. IR spectroscopic data showed that the amorphous phase of such films is enriched with T 3 GT 3 G − isomers. This is accompanied by an increase in their high-voltage conductivity. Despite the crystallization mainly in nonpolar α-phase, a domain structure was recorded in the films by piezo force microscopy. Surface structuring processes, accompanied by the displacement of certain attachment chain defects into the surface, have been recorded using IR spectroscopy. The presence of such intrachain defects is confirmed and characterized by high-resolution 19 F NMR.