纳米添加物-聚合物界面效应增强PVDF基三聚物纳米复合材料的介电响应  

Dielectric responses enhanced by nanofiller-polymer interfaces in PVDF-based terpolymer nanocomposites

作　　者：车亚萍 初宝进[1] 谭启 CHE Yaping;CHU Baojin;TAN Qi(CAS Key Laboratory of Materials for Energy Conversion, and Department of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026, China;Guangdong Technion Israel Institute of Technology, Shantou 515063, China)

机构地区：[1]中国科学技术大学材料科学与工程系,中国科学院能量转换材料重点实验室,安徽合肥230026 [2]广东以色列理工学院,广东汕头515063

出　　处：《中国科学技术大学学报》2020年第6期758-768,共11页JUSTC

基　　金：the National Key Research and Development Program of China(2017YFA0701301);the National Natural Science Foundation of China(51672261,51373161);the Start-up Fund of Guangdong Technion Israel Institute of Technology.

摘　　要：在纳米复合材料中,随着纳米颗粒尺寸的减小,纳米颗粒与聚合物基体间的界面起着越来越大的作用.为此以P(VDF-TrFE-CFE)三元共聚物作为聚合物基体,以低介电系数的SiO_(2)和高介电系数的BaTiO_(3)纳米颗粒为填料研究了界面的增强效应.对于这两种纳米颗粒,当体积分数低于1%时,其介电系数和极化响应均出现异常的增加.这些增加与纳米颗粒本身的介电性能及三聚物的结晶度变化无关.聚合物中的结晶相由非极性结构向极性结构有轻微的转变,因此提高了界面区域的介电响应.对此提出一种界面模型,解释了界面区域的非均匀介电响应是引起该介电现象的主要原因.在某一纳米颗粒含量下,界面区域的重叠可带来纳米复合材料最大的介电响应.The interfaces between nanofillers and the polymer matrix in nanocomposites are known to be increasingly important when nanofillers become smaller.A P(VDF-TrFE-CFE)terpolymer is used as the template polymer matrix and low-K(dielectric constant)SiO_(2) and high-K BaTiO_(3) nanoparticles as fillers to determine the enhancement effect of the interfaces.For both kinds of fillers,anomalous increases in the dielectric constant and polarization response are observed at nanoparticle loading less than 1%(volume fraction).These increases are not related to the intrinsic dielectric properties of the nanofillers and the change of crystallinity of the terpolymer.The crystalline phase is slightly changed from a non-polar structure towards a more polar one,improving the dielectric response in the interfacial regions.An interfacial model is proposed and the non-uniform dielectric response of the interfacial regions is responsible for the observed dielectric phenomena.The overlapping of the interfacial regions leads to the maximum dielectric response of the nanocomposites with certain particle loading.

关 键 词：介电材料 纳米复合物 界面效应 三聚物 

分 类 号：TB33[一般工业技术—材料科学与工程]