Institute of Electrical Engineering, Chinese Academy of Science, Beijing, 100190, China.
School of Engineering Science, University of Chinese Academy of Sciences, Beijing, 100049, China.
Macromol Rapid Commun. 2023 Nov;44(22):e2300372. doi: 10.1002/marc.202300372. Epub 2023 Oct 2.
The development of high-temperature resistant dielectrics with excellent dielectric properties and self-healing behavior is crucial for the application of metallized film capacitors. In this work, a series of polyetherimide (PEI) dielectric films are designed and fabricated. The introduction of polar groups is in favor to the increase of permittivity, and the flexible connection such as the ether group will facilitate the reduction of dielectric loss. Moreover, the oxygen elements are beneficial to the "self-healing" of metallized film capacitors. Consequently, the permittivity of 3.53-4.00, dissipation factor of 0.281-0.517%, and Weibull breakdown strength of 347-674 MV m are obtained for the PEI dielectrics. In addition, PEI-4 (BPADA-BAPP) and PEI-8 (BPADA-MDA) are selected to further investigate dielectric breakdown (150 °C), electrical displacement-electric filed (D-E) loop (at room temperature and 150 °C) as well as self-healing performance, which will evaluate their potential in practical applications. The results show that PEI-8 has stable breakdown field strength and high charge-discharge efficiency at elevated temperatures. Metallized film capacitor based on PEI-8 exhibits excellent self-healing performance, with pleasing self-clear morphology, high breakdown voltage, and reduced self-healing energy. Therefore, PEI-8 is considered as a potential candidate for metallized film capacitors applied under harsh conditions.
开发具有优异介电性能和自修复行为的耐高温电介质对于金属化膜电容器的应用至关重要。在这项工作中，设计并制备了一系列聚醚酰亚胺（PEI）电介质薄膜。引入极性基团有利于介电常数的增加，而醚键等柔性连接有利于降低介电损耗。此外，氧元素有利于金属化膜电容器的“自修复”。因此，PEI 电介质的介电常数为 3.53-4.00，损耗因数为 0.281-0.517%，Weibull 击穿强度为 347-674 MV m。此外，选择 PEI-4（BPADA-BAPP）和 PEI-8（BPADA-MDA）进一步研究介电击穿（150°C）、电位移-电场（D-E）循环（在室温下和 150°C）以及自修复性能，这将评估它们在实际应用中的潜力。结果表明，PEI-8 在高温下具有稳定的击穿场强和较高的电荷放电效率。基于 PEI-8 的金属化膜电容器表现出优异的自修复性能，具有令人满意的自清除形态、高击穿电压和降低的自修复能量。因此，PEI-8 被认为是在恶劣条件下应用的金属化膜电容器的潜在候选材料。
