Ferroelectric properties of vinylidene fluoride-trifluoroethylene copolymers

Kitayama, Toyoki

doi:10.1063/1.328679

Cited by 80 publications

(28 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The copolymer crystal structure, phase transition behavior and ferroelectric properties are affected by the ratio of VDF/fluoride-trifluoroethylene (TrFE) content and the synthesizing conditions [10]. Similar to PVDF, P(VDF-TrFE) has been reported to crystallize into four types of crystalline phases (α,β,γ,δ).…”

Section: Introductionmentioning

confidence: 99%

Hot Plate Annealing at a Low Temperature of a Thin Ferroelectric P(VDF-TrFE) Film with an Improved Crystalline Structure for Sensors and Actuators

Mahdi

Gan

Majid

2014

Sensors

108

View full text Add to dashboard Cite

Ferroelectric poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) copolymer 70/30 thin films are prepared by spin coating. The crystalline structure of these films is investigated by varying the annealing temperature from the ferroelectric phase to the paraelectric phase. A hot plate was used to produce a direct and an efficient annealing effect on the thin film. The dielectric, ferroelectric and pyroelectric properties of the P(VDF-TrFE) thin films are measured as a function of different annealing temperatures (80 to 140 °C). It was found that an annealing temperature of 100 °C (slightly above the Curie temperature, Tc) has induced a highly crystalline β phase with a rod-like crystal structure, as examined by X-ray. Such a crystal structure yields a high remanent polarization, Pr = 94 mC/m2, and pyroelectric constant, p = 24 μC/m2K. A higher annealing temperature exhibits an elongated needle-like crystal domain, resulting in a decrease in the crystalline structure and the functional electrical properties. This study revealed that highly crystalline P(VDF-TrFE) thin films could be induced at 100 °C by annealing the thin film with a simple and cheap method.

show abstract

Section: Introductionmentioning

confidence: 99%

Hot Plate Annealing at a Low Temperature of a Thin Ferroelectric P(VDF-TrFE) Film with an Improved Crystalline Structure for Sensors and Actuators

Mahdi

Gan

Majid

2014

Sensors

108

View full text Add to dashboard Cite

show abstract

“…Thin films are often prepared by solvent casting , spin‐coating , hot pressing/compression molding , or Langmuir–Blodgett deposition for different thicknesses and applications. A critical thickness of crystallization of P(VDF‐TrFE) thin films was observed at about 100 nm ; the crystallization for thinner films is strongly inhibited, resulting in a decrease of crystallinity, dielectric constant, and remanent polarization.…”

Section: Introductionmentioning

confidence: 99%

Effect of ultrasonication and other processing conditions on the morphology, thermomechanical, and piezoelectric properties of poly(vinylidene difluoride-trifluoroethylene) copolymer films

et al. 2013

View full text Add to dashboard Cite

International audienceThis study is carried out on the effect of processing conditions including preparation methods, ultrasonication, film thickness, and thermal annealing on the thermal, mechanical, and piezoelectric properties of copolymer of poly(vinylidene difluoride-trifluoroethylene) (P(VDF-TrFE)). Free-standing films and films on substrates are prepared by solvent casting and spin-coating, respectively. The results obtained by differential scanning calorimetry show that the Curie transition of the copolymer films was influenced by the preparation methods, with very little difference in the melting transition. The difference was attributed to a less uniform distribution of TrFE comonomer units within the crystalline and amorphous regions of the spin-coating films. However, no effect of the preparation methods on the piezoelectric properties of the films was observed. It is also found that the short ultrasonication, film thickness higher than critical value of crystallization of P(VDF-TrFE) (about 100 nm), and drying before annealing did not have a significant effect on the properties of the films. Surprisingly, the ultrasonication had a clear impact on the relaxations at high temperature of the polymer chains. In addition, this study indicates that a short annealing by 10 min at 140 degrees C was enough to obtain well-crystallized films, which is interesting from the industrial point of view

show abstract

“…Moreover, the vinylidene fluoride-trifluoroethylene [P(VDF-TrFE)] copolymer containing from 50 to 80 wt % PVDF undergoes a ferroelectric phase transition [6,7], which is not observed in pure PVDF. The degree of crystallinity of the P(VDF-TrFE) copolymer can be as high as 90% [8].…”

Section: Introductionmentioning

confidence: 99%

10.1007/s11451-008-3028-2

2010

CrossRef Listing of Deleted DOIs

View full text Add to dashboard Cite

The temperature dependences of the real and imaginary parts of the complex permittivity of vinylidene fluoride-trifluoroethylene copolymer films at temperatures ranging from -40 to 140 ° C are determined in the frequency range 10 -1 -10 8 Hz. An analysis of the experimental data has demonstrated that the behavior of the dielectric characteristics of the copolymer in the course of heating to temperatures above the ferroelectric phase transition point and during subsequent cooling differs substantially. In the latter case, the high-frequency dielectric response exhibits properties characteristic of relaxor ferroelectrics. The observed features are discussed in terms of the competition of two mechanisms associated with the short-range and long-range forces.

show abstract

Ferroelectric properties of vinylidene fluoride-trifluoroethylene copolymers

Cited by 80 publications

References 25 publications

Hot Plate Annealing at a Low Temperature of a Thin Ferroelectric P(VDF-TrFE) Film with an Improved Crystalline Structure for Sensors and Actuators

Hot Plate Annealing at a Low Temperature of a Thin Ferroelectric P(VDF-TrFE) Film with an Improved Crystalline Structure for Sensors and Actuators

Effect of ultrasonication and other processing conditions on the morphology, thermomechanical, and piezoelectric properties of poly(vinylidene difluoride-trifluoroethylene) copolymer films

10.1007/s11451-008-3028-2

Contact Info

Product

Resources

About