Growth of Single Crystals of Poly(vinylidene fluoride) under High Pressures

Publisher Website
Google Scholar
Abstract
Lamellar crystals of poly(vinylidene fluoride) about 0.2 µm thick and 10 µm wide are grown in films crystallized at high pressures and high temperatures. Electron diffraction shows that the lamellar crystal is a β-form single crystal composed of all-trans extended chains. DSC and crystallization studies suggest that the β-form crystals are grown in the paraelectric or hexagonal phase which appears above 2.0 kb and 260°C in the heating process and above 2.0 kb and 210°C in the solidification process. The phase diagram of PVDF is proposed. The β-form film has distinctive ferroelectricity and strong piezoelectricity: P r=100 mC/m2 and E c=75 MV/m, and k t=0.2.