Properties of clay nanocomposites based on poly(vinylidene fluoride-co- hexafluoropropylene)

Abstract

Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) nanocomposites with different contents of nanoclays were prepared by melt mixing. The clays used included unmodified clays, a commercially available hydrophilic nanoclay based on bentonite (nanoclay 1) and organically modified clay based on montmorillonite (nanoclay 2). The nanocomposites obtained were analyzed by x-ray diffraction, differential thermal and differential scanning calorimetry analyses and their basic tensile and other characteristics were determined. The distribution of the filler throughout the matrix was found to be good for both the types of nanocomposite materials. Nanoclay 1 induced slight increase in the b-phase and higher deviation of the main diffractions (2 ¼ 18.6 and 20.1 at 10 mass% filler). The degree of crystallinity of the materials containing nanoclay 2 decreased from 26.4 to 20.5% and from 23.9 to 18.7%, respectively, for the first and second heating. The tensile strength of the materials based on PVDF-HFP with nanoclays 1 and 2 was close to that of the initial copolymer or slightly increased with the addition of nanoclay 2. Young's modulus was in the range of 215-265 MPa. The heat resistance by Vicat increased by 7 C compared with the initial copolymer.

Modified Thermal, Dielectric, and Electrical Conductivity of PVDF-HFP/LiClO4Polymer Electrolyte Films by 8 MeV Electron Beam Irradiation

“…The result confirms the increased amorphisity in the irradiated polymer film. 31,32 This observation is in correlation with the XRD results.…”

High diffusion barrier and piezoelectric nanocomposites based on polyvinylidene fluoride‐trifluoroethylene copolymer and hydrophobized clay

“…The T C and T m of the composites on the other hand were generally equal to slightly higher than for the polymer, possibly indicating a somewhat more perfect crystalline phase. The decrease of crystallinity with addition of clay has been observed in other studies; however, the β phase fraction is usually reported to increase . In this case, it seems that the presence of clay somewhat hindered the growth of β phase crystals during annealing, so that the fraction of β phase increased more rapidly with annealing time in the polymer than in the composites, although eventually reached similar values in all materials.…”

Modified sepiolite/PVDF‐HFP composite film with enhanced piezoelectric and dielectric properties

“…In addition, for the dielectric properties of PVDF, ceramics, and graphene oxide were usually used as fillers to further enhance the dielectric properties of pure PVDF. Moreover, the dielectric and piezoelectric properties could be enhanced simultaneously by adding nanoparticles (such as Fe 2 O 3 and Co 3 O 4 ), metallic nanoparticles (such as triturated copper and cobalt), and clay (montmorillonite [MMT]) as fillers in the PVDF‐ co ‐hexafluoropropylene (PVDF‐HFP) matrix.…”

“…Clay minerals, such as MMT, kaolinite, halloysite, attapulgite, palygorskite, and sepiolite (SEP), were widely used as green fillers in polymer matrix in order to enhance the performance of polymer, such as the phase crystallization and electrical properties . For the MMT/PVDF composites reported previously, the piezoelectric and dielectric could be improved at the same time . The MMT induced the polarization of PVDF‐HFP by the hydrogen bonds between F atoms of PVDF‐HFP and OH of MMT.…”