Non-linear dielectric spectroscopy for detecting and evaluating structure-property relations in a P(VDF-TrFE-CFE) relaxor-ferroelectric terpolymer

Abstract

Non-linear dielectric spectroscopy (NLDS) is employed as an effective tool to study relaxation processes and phase transitions of a poly(vinylidenefluoride-trifluoroethylene-chlorofluoroethylene) (P(VDF-TrFE-CFE)) relaxor-ferroelectric (R-F) terpolymer in detail. Measurements of the non-linear dielectric permittivity $${\varepsilon _{2}^{'}}$$ ε 2 ′ reveal peaks at 30 and 80$$\,^\circ$$ ∘ C that cannot be identified in conventional dielectric spectroscopy. By combining the results from NLDS experiments with those from other techniques such as thermally stimulated depolarization and dielectric-hysteresis studies, it is possible to explain the processes behind the additional peaks. The former peak, which is associated with the mid-temperature transition, is found in all other vinylidene fluoride-based polymers and may help to understand the non-zero $$\varepsilon _\mathrm {2}^{'}$$ ε 2 ′ values that are detected on the paraelectric phase of the terpolymer. The latter peak can also be observed during cooling of P(VDF-TrFE) copolymer samples at 100$$\,^\circ$$ ∘ C and is due to conduction and space-charge polarization as a result of the accumulation of real charges at the electrode–sample interface.

Tuning the Relaxor–Ferroelectric Properties of Poly(vinylidene fluoride–trifluoroethylene–chlorofluoroethylene) Terpolymer Films by Means of Thermally Induced Micro- and Nanostructures

“…Furthermore, the high-temperature dielectric-loss peak around 100 °C on the nonannealed sample is removed as a result of heat treatments at high or intermediate temperatures. The loss peak that disappeared after intermediate- or high-temperature annealing is associated with electrode polarization, as typically observed at temperatures near the melting point of a terpolymer sample …”

“…The loss peak that disappeared after intermediate-or hightemperature annealing is associated with electrode polarization, as typically observed at temperatures near the melting point of a terpolymer sample. 15 The thermal behavior of either nonannealed or annealed, freestanding terpolymer films is shown in Figure 2, which consists of DSC traces during the first heating. At temperatures below 0 °C, we observe the glass-transition step for all of the terpolymer samples.…”

Synthesis of Bottlebrush Polymers with Spontaneous Self-Assembly for Dielectric Generators

“…Phase segregation introduces interfaces that lead to Maxwell–Wagner Interface (MWI) polarization, which occurs above T g and can be observed by impedance spectroscopy. , Looking at Figure b, which shows the Arrhenius plot of the high-temperature relaxation observed in Figure a, we can assign the Arrhenius type of relaxation behavior with a higher activation energy to MWI polarization. However, it is important to consider the contributions from electrode polarization, whose effects are observed at these elevated temperatures and low frequencies, leading to electrical conductivity relaxation (ECR) . This typically arises due to an accumulation of space charges at the interface of the electrode and the dielectric sample.…”

Strategies Involved in Enhancing the Capacitive Energy Storage Characteristics of Poly(vinylidene fluoride) Based Flexible Composites

“…As PVDF exhibits non‐linear dielectric characteristics, its energy storage density can not be determined by straightway utilizing Equation 1 as described earlier [121–123] . The energy storage density and efficiency of this type of composites are commonly determined from their electric field ( E ) dependent polarization ( P ) or electric displacement ( D ) hysteresis loops ( P‐E or D‐E loops) [124,125] as shown in Figure 2.…”

“…As PVDF exhibits non-linear dielectric characteristics, its energy storage density can not be determined by straightway utilizing Equation 1 as described earlier. [121][122][123] The energy storage density and efficiency of this type of composites are commonly determined from their electric field (E) dependent polarization (P) or electric displacement (D) hysteresis loops (P-E or D-E loops) [124,125] as shown in Figure 2. By proper loop area calculation within specific limits stored energy density (U stored ) and energy loss density (U loss ) could be determined and hence efficiency (η) could be calculated.…”