Electrospinning of PVDF nanofibrous membranes with controllable crystalline phases

P(VDF-TrFE) nanofibers: structure of the ferroelectric and paraelectric phases through IR and Raman spectroscopies

“…Electrospinning not only represents an effective method to improve the b phase content in uorinated polymers and copolymers, but it also opens to a wide range of nanostructurebased devices. PVDF [65][66][67][68][69][70][71][72] and P(VDF-TrFE) 9,11,34,[37][38][39]52,53,[73][74][75][76][77][78] nanobers also offer the advantages of electrospinning to develop materials with a macroscopic orientation of the polymer chains.…”

A critical analysis of the α, β and γ phases in poly(vinylidene fluoride) using FTIR

“…However, peaks in the range of 876-885, 1067-1075, 1171-1182 and 1398-1404 cm À1 have similar characteristics in samples of a-, band g-phases or other mixed systems. 19,21,22,46,65,66,73,74,100,103 In other words, these are common peaks that appear in all three phases. The exclusive peaks can be used to identify the corresponding crystalline phases, whereas the dual peaks may be the results of experimental uncertainty for small wavenumber shis (typically within 2 cm À1 ), or truely different phases depending on experimental conditions.…”

“…20,80,85,104,105 The 600 cm À1 band that was previously assigned to the b-phase by some authors, 17,38,101,106 should not be used to characterize PVDF as this band is commonly showed up in many samples, including a-phase ones, due to the other intensive peak around at 613 cm À1 . 11,12,16,18,20,29,31,46,51,107,108 It is noted that the 776 and 833 cm À1 bands exclusively shown in high temperature crystallization g-phase, 18,68,109 are rather seldom observed in other g-phase domination samples. 14,19,40,42,55,69,70,85 Since the amounts of the three phases can be in any percentage, establishing a universal but simplied procedure to trace these phases is therefore of great signicance.…”

Durable, efficient, and flexible piezoelectric nanogenerator from electrospun PANi/HNT/PVDF blend nanocomposite

“…Due to the electrostatic forces, fibers are stretched and become ultrafine fibers . Due to the applied voltage and stretching of fibers, α‐phase of PVDF transforms into β‐phase that is electroactive and could be useful as a piezoelectric nanogenerator . PNFs of small diameter possess higher energy conversion efficiency compared with PVDF films .…”