Preparation and properties of β‐phase graphene oxide/PVDF composite films

Abstract

We report preparation of graphene oxide (GO) from expanded graphite (EG) via a modified Hummers method. GO/ PVDF composites films were obtained using solvent N, N-Dimethylformamide (DMF) and cosolvent comprising deionized water/ DMF combination. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses revealed that the main crystal structure of the composite films is b-phase, and use cosolvent method tends to favor the formation of b-phase. Scanning electron microscopy (SEM) was used to investigate the microstructure of composite films. Storage modulus and loss modulus were measured by Dynamic mechanical analysis (DMA). Broadband dielectric spectrum tests showed an increase in the dielectric constant of the GO/PVDF composite films with the rising content of GO, and by cosolvent method could improve the dielectric constant while reducing the dielectric loss. Our method that uses GO as an additive and deionized water/DMF as the cosolvent provides a promising and low-cost pathway to obtain high dielectric materials.

Fabrication of flexible and self-standing inorganic–organic three phase magneto-dielectric PVDF based multiferroic nanocomposite films through a small loading of graphene oxide (GO) and Fe3O4nanoparticles

“…The addition of GO or Fe 3 O 4 or both to PVDF decreases the α-phase and partially converts it into β-phase PVDF in composite films. 39 The XRD patterns of GO and Fe 3 O 4 nanoparticles are also shown for comparison with the characteristic peak of GO at 2θ = 9.6°. As the concentrations of both GO and Fe 3 O 4 are only 5% in the composite films, their corresponding peaks in the XRD pattern are very weak, specifically for GO (inset, Fig.…”

Novel electrospun polyvinylidene fluoride-graphene oxide-silver nanocomposite membranes with protein and bacterial antifouling characteristics

“…In general, nanomaterials can also induce the formation of β-phase PVDF. In particular, AgNPs, GO or rGO addition promotes the formation of β-phase PVDF [57,62,63]. Manna et al [57] reported that an electrostatic interaction between the charges on AgNPs and the CF 2 dipole of PVDF straightens the PVF 2 chains, leading to the formation of β-phase conformation.…”

Physico-Mechanical, Dielectric, and Piezoelectric Properties of PVDF Electrospun Mats Containing Silver Nanoparticles

“…There are different methods to increase the β-phase content, such as mechanical stretching, use of polar solvents to dissolve and re-crystallize PVDF, electrical poling, and addition of fillers [5][6][7][8]. An example is graphene oxide (GO), which increases the β-phase content via interaction of the polymer chain with the oxygen-rich groups on the surfaces of the GO layers [9,10], or cellulose, where the polymer interacts with the -OH groups [2,11]. In addition, electron clouds on the surfaces of the metal nanoparticles could interact with polymer chains resulting in enhancement of the β-phase content [12].…”