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The structure and properties of block poly(vinylidene fluoride) and systems based on it

“…For example, according to the results of McBrierty et al, 317 the relaxation process, associated with the motion of the folds on the surface of the lamellae and noted in experiments on dynamic mechanical relaxation by the dielectric method, was not observed. A similar conclusion was reached in a study 318 where two mechanical relaxation regions (ai and ofe) were found in all the PVDF specimens (isotropic and oriented with the crystals of the a and p modifications) at high temperatures, the higher-temperature region (012) being assigned to the motions preceding the fusion of the crystal. It follows from the results of the study that the mechanisms of the relaxation in mechanical and electric fields in the region of the glass transition of the oriented specimens may differ.…”

“…It follows from the results of the study that the mechanisms of the relaxation in mechanical and electric fields in the region of the glass transition of the oriented specimens may differ. This is indicated, in particular, by the finding that, in a mechanical field, the f$ process is more intense in the case of a parallel disposition of the force vector and the orientation axis, 318 whereas in an electric field the opposite behaviour obtains. 293 - 297 An attempt has been made at a detailed comparison of the relaxation processes in PVDF and polyethylene on the basis of the results obtained by mechanical spectroscopy.…”

Dielectric relaxation in vinylidene fluoride–hexafluoropropylene copolymers

“…It can lead to the sharp increase in dielectric permittivity (Figs. 13 and 14) that, in its turn, will lead to decrease in dissociation energy W of impurities in relations (15) and (16). Thus, one should expect additional increase in number of mobile carriers n 0 in the system.…”