Abstract
This paper discusses a new family of ferroelectric polymorphs fluoro-terpolymers comprising vinylidene difluoride (VDF), trifluoroethylene (TrFE), and a chloro-containing third monomer, including vinyl chloride (VC), 1,1-chlorofluoroethylene (CFE), chlorodifluoroethylene (CDFE), chlorotrifluoroethylene (CTFE), with narrow molecular weight and composition distributions. The slightly bulky chlorine atom serves as a kink in the polymer chain, which spontaneously alters the chain conformation and crystalline structure. Comparing with the corresponding VDF/TrFE copolymer, the slowly increasing chlorine content (< 8 mol% of ter-monomer) gradually changes the all-trans chain conformation to tttg+tttg- conformation, without significant reduction of overall crystallinity. Curie (F-P) phase transition temperature between the mixed ferroelectric phases and paraelectric phase (tg+tg- conformation) also gradually reduced to near ambient temperature, with very small activation energy. Consequently, the terpolymers show high dielectric constant (>80) and large electrostrictive response (>5%) at ambient temperature, and exhibiting common ferroelectric relaxor behaviors with a broad dielectric peak that shifted toward higher temperatures as the frequency increased, and a slim polarization hysteresis loop at ambient temperature.
Original language | English (US) |
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Pages (from-to) | 41-50 |
Number of pages | 10 |
Journal | Proceedings of SPIE - The International Society for Optical Engineering |
Volume | 5053 |
DOIs | |
State | Published - 2003 |
Event | PROCEEDINGS OF SPIE SPIE - The International Society for Optical Engineering: Smart Structures and Materials 2003 Active Materials: Behavior and Mechanics - San Diego, CA, United States Duration: Mar 3 2003 → Mar 6 2003 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering