Dielectric behavior and electrical conductivity of PVDF filled with functionalized single-walled carbon nanotubes

Abstract

Polyvinylidene fluoride (PVDF)/ single-walled carbon nanotube (SWCNT) composites are characterized by X-ray diffraction and scanning calorimetry, and studied by dielectric relaxation spectroscopy (DRS) in the temperature range of -75 to 150ºC. The effects of SWCNTs and SWCNT functionalization are analyzed in terms of α and α c relaxation, dielectric permittivity, loss tangent, and AC electrical conductivity. Some small changes are detected in α relaxation with the addition of SWCNTs, and a strong influence of SWCNTs is observed in the other relaxation α c . Below the percolation threshold, the dielectric permittivity of functionalized SWCNT composites increases compared to blank PVDF, without notable changes in the dielectric loss. All the composite systems show an electrical percolation behavior with different thresholds depending on SWCNT functionalization. Threshold concentrations remain nearly unchanged in the whole temperature and frequency ranges. The base PVDF conductivity strongly depends on temperature and frequency, while the maximum conductivity above the percolation remains nearly unchanged (~ 10 -2 S/m) for all the systems, temperatures and frequencies.

The effect of thermal treatment on ac/dc conductivity and current fluctuations of PVDF/NMP/[EMIM][TFSI] solid polymer electrolyte

“…The experimental data was fitted by parameters (E a = 47.72 meV, T g = 165 K, σ ∞ = 58 S/m) that lay within published limits 54,55 . www.nature.com/scientificreports/ with the temperature 24,56 . Its real part, σ′, increases with frequency, but also contains an intermediate frequency plateau for all temperatures 56 .…”

“…The SPE consisted of three basic components: ionic liquid, polymer matrix and solvent. The frequency-dependent electrical conductivity of neat PVDF rises with the temperature 24 , 56 . Its real part, σ′, increases with frequency, but also contains an intermediate frequency plateau for all temperatures 56 .…”

“…There are many existing methods of modifying the conductivity of the polymer electrolyte, such as blending, copolymerization, cross-linking and the addition of additives 1,2,4,[21][22][23][24] . The blending and adding nanofillers (such as carbon powder, nanowires, SWCNT, etc.)…”

Preparation of Flexible Self‐Supporting 3D SiOx‐Based Membrane Anodes with Stabilized Electrochemical Performances for Lithium‐Ion Batteries

“…Due to the outer protection of SiO x , the membrane solves the adverse effects caused by the volume expansion and electrical contact loss of SiO x during the alloying/dealloying. As an inert and high molecular fluoropolymer with a high dielectric constant, mechanical properties, thermal stability, corrosion resistance, and other interesting features, PVDF is widely applied in numerous fields such as tactile sensors, infrared imaging devices, actuators, electrolytic gated transistors, and the like . In addition, PVDF has a reasonable Young's modulus and can act as a soft and deformable elastomer to form a buffered matrix that improves the mechanical stability and to alleviate the volume changes of SiO x active material during the cycling process.…”

Electronic Transport Mechanisms in PVDF/ZnO Nanocomposite Films

“…It has an expeditious response time, very low density, and eminent pliability when compared to electroactive ceramics and shape memory alloys. The piezoelectric PVDF and its copolymers have wide applications in actuators and sensors [11]. These materials are utilized as fibers and films in engineering applications such as piezo-laminated columns, active micro air vehicle wings, and shape correction films in space applications where linear movement is required.…”