Semicrystalline Ferroelectric Fluoropolymers and Process for Preparing Same
Abstract
A new class of ferroelectric terpolymers having an exceptionally large electrostrictive response (> 3%) induced by external electric field at ambient temperature comprise 50-80 mole % of vinylidene fluoride (VDF), 15-40 mole % of trifluoroethylene (TrFE) and 2-20 mole % of at least one bulky monomer, such as chlorotrifluoroethylene (CTFE) or hexafluoropropene (HFP). These semicrystalline terpolymers behave like a ferroelectric relaxor having a rapid electric field-induced mechanical response se, due to a low Curie temperature (phase transition between polar and nonpolar crystalline domains at or near ambient temperature) and high dielectric constant. A combination of bulk polymerization and free radical polymerization using oxidation adducts of an organoborane as the free radical initiator may be used to prepare the terpolymers, such that the terpolymers are characterized by good processibility, high purity and uniform molecular structure.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 05, 2000
- Accession Number
- ADD019990
Entities
People
- Tze-chiang Chung
Organizations
- United States Department of the Navy