Journal
ACS APPLIED MATERIALS & INTERFACES
Volume 6, Issue 21, Pages 18981-18988Publisher
AMER CHEMICAL SOC
DOI: 10.1021/am504874f
Keywords
ferroelectric polymers; poly(vinylidene fluoride); dielectric properties; capacitors; energy storage
Funding
- Dow Chemical Company
- Office of Naval Research
Ask authors/readers for more resources
Poly(vinylidene fluoride) PVDF-based copolymers represent the state of the art dielectric polymers for high energy density capacitors. Past work on these copolymers has been done with limited emphasis on the effects of copolymer composition and with a limited range of defect monomers, focusing primarily on the commercially available poly(vinylidene fluoride-co-chlorotrifluoroethylene), P(VDF-CTFE), and poly(vinylidene fluoride-co-hexafluoropropylene), P(VDF-HFP), and the processing thereof. To expand on this area of research, copolymers of VDF and bromotrifluoroethylene (BTFE) were synthesized examining the composition range where uniaxial stretching was possible. It is found that P(VDF-BTFE) copolymers with small BTFE contents (<2 mol %) stabilize the gamma phase, compared to P(VDF-CTFE)s and P(VDF-HFP)s that are largely a phase in composition. Furthermore, different from P(VDF-CTFE)s and P(VDF-HFP)s, whose energy storage capabilities depend on the reversibility of the alpha to beta phases transformation, high discharged energy densities (i.e., 20.8 J/cm(3) at 716 MV/m) are also achievable through the beta and gamma phases in P(VDF-BTFE)s without significantly reducing crystallinity and breakdown strength. This study demonstrates new avenues to the development of high energy density ferroelectric copolymers via manipulation of the gamma phase through variation of the structure and content of comonomers.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available