Non‐destructive thermal ageing evaluation of P (VDF‐HFP) film based on broadband dielectric response
Non‐destructive thermal ageing evaluation of P (VDF‐HFP) film based on broadband dielectric response
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DOI：
10.1049/hve2.12236
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发表时间：
2022-07
期刊：
影响因子：
4.4
通讯作者：
Qian Wang;Chao Wu;Yanfeng Gao;Shuming Liu;Shuqi Liu;Z. Zuo;Xidong Liang
中科院分区：
文献类型：
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作者：
Qian Wang;Chao Wu;Yanfeng Gao;Shuming Liu;Shuqi Liu;Z. Zuo;Xidong Liang
基于聚合物介电材料的电容器和传感器是电气系统和电子设备中的关键部件。采用溶液浇铸法制备了厚度为20 μm的P（VDF-HFP）薄膜，并进行了长达1000 h的热老化实验。测量了不同老化时间的样品在宽温度和频率范围内的介电响应。应用普适弛豫定律和Dissado-Hill介电响应模型对结果进行了进一步的研究。得到了各个过程的特征，这表明Vogel-Fulcher-Tammann方程的主链松弛和Arrhenius方程的侧链松弛在热老化后保持不变。但是，这两个过程的活化能在过程中变化很大，并表现出不同的变化趋势。由于退火和晶区断裂的影响，侧链松弛的活化能单调增大。据此提出了一种P（VDF-HFP）热老化的无损评价方法。
Capacitors and sensors based on polymer dielectric materials are key components in electrical systems and electronic devices. Considering the temperature rise during operation, an effective evaluation method for the thermal ageing of polymer matrix is urgently needed.P(VDF‐HFP) film with a thickness of 20 μm is manufactured by solution casting and a thermal ageing experiment up to 1000 h is conducted. Dielectric responses of wide ranges of temperatures and frequencies are measured for samples with different ageing durations. The universal relaxation law and Dissado–Hill dielectric response model are applied to further investigate the results. The characteristics of individual processes are obtained, which demonstrate that the main chain relaxation following the Vogel−Fulcher−Tammann equation and side chain relaxation following the Arrhenius equation both remain unchanged after thermal ageing. However, the activation energies of those two processes change significantly during the process and show different variation trends. The activation energy of the side chain relaxation gets larger monotonically due to the influence of annealing and the breaking of crystalline region. As a result, a non‐destructive evaluation method for the thermal ageing ofP(VDF‐HFP) is proposed accordingly.