Constantino, CJLJob, A. E.Simoes, R. D.Giacometti, J. A.Zucolotto, VOliveira, O. N.Gozzi, G.Chinaglia, D. L.2014-05-202014-05-202005-03-01Applied Spectroscopy. Frederick: Soc Applied Spectroscopy, v. 59, n. 3, p. 275-279, 2005.0003-7028http://hdl.handle.net/11449/32747The phase transition from the non-polar a-phase to the polar beta-phase of poly(vinylidene fluoride) (PVDF) has been investigated using micro-Raman spectroscopy, which is advantageous because it is a nondestructive technique. Films of alpha-PVDF were subjected to stretching under controlled rates at 80 degrees C, while the transition to P-PVDF was monitored by the decrease in the Raman band at 794 cm(-1) characteristic of the a-phase, along with the concomitant increase in the 839 cm-1 band characteristic of the P-phase. The alpha ->beta transition in our PVDF samples could be achieved even for the sample stretched to twice (2 X -stretched) the initial length and it did not depend on the stretching rate in the range between 2.0 and 7.0 mm/min. These conclusions were corroborated by differential scanning calorimetry (DSC) and X-ray diffraction experiments for PVDF samples processed under the same conditions as in the Raman scattering measurements. Poling with negative corona discharge was found to affect the a-PVDF morphology, improving the Raman bands related to this crystalline phase. This effect is minimized for films stretched to higher ratios. Significantly, corona-induced effects could not be observed with the other experimental techniques, i.e., X-ray diffraction and infrared spectroscopy.275-279engpoly(vinylidene fluoride)PVDFmicro-Raman spectroscopydifferential scanning calorimetryDSCX-ray diffractionXRDArtigo10.1366/0003702053585336WOS:000227680400002Acesso restrito887053974982106715405387246192960000-0002-4556-3718