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博士研究生夏卫民文章被Journal of Polymer Science Part B: Polymer Physics接收
发布者: 张志成 | 2012-07-19 | 774

            博士研究生夏卫民论文“Dependence of Dielectric, Ferroelectric, and Piezoelectric Properties on Crystalline Properties of P(VDF-co-TrFE) Copolymers” 被Journal of Polymer Science Part B: Polymer Physics 接收。

 

       该文中重点讨论了P(VDF-co-TrFE)共聚物的结晶性能对其介电、铁电以及压电性能的影响,研究发现不同的热处理方式会导致共聚物结晶度以及晶体颗粒尺寸大小的不同,同时晶片的大小改变也会导致其相应电性能的不同。摘要如下:

 

    Thermal processing at various temperatures has been used to fabricate poly(vinylidene fluoride-co-trifluoroethylene) [P(VDF-co-TrFE)] films with varied crystalline properties in an attempt to improve their piezoelectric properties. Although the dielectric constant of the films annealed at higher temperature is smaller than that of cooled and quenched ones, it has been shown that the annealed films possess larger crystallinity and stacked lamellar crystal grain size. The ferroelectric domains deriving from crystal region in all the samples are effectively improved by hot polarization. As a result, the remnant polarizations (Pr) and coercive electric field (Ec) of the corresponding films are improved at a low frequency due to the response of dipoles in crystal phase, and the largest piezoelectric constant in the longitudinal thickness mode (d33=-25 pC/N) is obtained in an annealed copolymer film. The results illustrate improving the crystal structure of P(VDF-co-TrFE) is an effective way to realize high electromechanical properties, which provides broadly applied scenery for this kind of copolymer
in piezoelectric components.