| 摘要 |
PURPOSE:To make it possible to form a dielectric polymer material having a high permittivity and being easily controlled in its permittivity by using a copolymer comprising vinylidene fluoride, trifluoroethylene and chlorotrifluoroethylene and specifying its compositional range. CONSTITUTION:The copolymer is formed from 60-79mol% vinylidene fluoride, 18-22mol% trifluoroethylene and 3-22mol% chlorotrifluoroethylene. This copolymer may contain other comonomers (e.g. tetrafluoroethylene or vinyl fluoride) of at most about 10wt.%, based on the copolymer. It is desirable that the copolymer has such an MW that the limiting viscosity [eta] (as measured in a solution of methyl ethyl ketone at 35 deg.C) of 0.2-2.0. The dielectric polymer material has a permittivity as high as about 30 or above at a measurement frequency of 1kHz. |
