Abstract：
Innovative dielectric materials with high-temperature resistance and outstanding dielectric properties have attracted tremendous attention in advanced electronical fields. Polyimide(PI) is considered a promising candidate for the modern electronic industry due to its excellent dielectric properties and comprehensive properties. However, the limited-adjustable range of dielectric constant and the difficulty to obtain a high dielectric constant restrict the application of PI as high dielectric materials. Herein, a novel diamine monomer (2,2\'-bis((methylsulfonyl)methyl)-[1,1\'-biphenyl]-4,4\'-diamine (BSBPA)) containing a rigid biphenyl structure and high dipolar sulfonyl pendant groups is designed for high dielectric polyimides. The rigid biphenyl and polar sulfonyl pendant groups can reasonably optimize the molecular structure and orientational polarization of polyimides to improve their dielectric properties and thermal properties. Moreover, the effect of different bridge linkages on the dielectric properties is studied by using the different dianhydrides. Thus, the PI-BSBPA films especially the DSDA-BSBPA film (DSDA: 3,3\',4,4\'-diphenylsulfonetetracarboxylic dianhydride) achieve great thermal properties (T5%d of 377 °C and Tg of 358 °C) and excellent dielectric properties (6.95 at 1 kHz) along with high discharged energy density of 5.25 J cm-3 and charge-discharge efficiency of 90%. The collaborative control of main-chain and side-chain engineering is effective to endow the polyimides with high-temperature tolerance and high dielectric performance.
摘要：
具有耐高温和优异介电性能的创新介电材料在先进电子领域引起了极大的关注。聚酰亚胺(PI)具有优异的介电性能和综合性能,被认为是现代电子工业中很有前途的候选材料。然而,介电常数可调范围有限，难以获得高介电常数限制了PI作为高介电材料的应用。在这里，一种新型二胺单体（2,2'-双（（甲基磺酰基）甲基）-[1,1'-联苯]-4,4'-二胺（BSBPA）），含有刚性联苯结构和高偶极磺酰基侧基设计用于高介电聚酰亚胺。刚性联苯基和极性磺酰基侧基可以合理优化聚酰亚胺的分子结构和取向极化，以改善其介电性能和热性能。此外，通过使用不同的二酐，研究了不同的桥键对介电性能的影响。因此，PI-BSBPA薄膜，尤其是DSDA-BSBPA薄膜(DSDA：3,3\'，4,4'-二苯基磺四羧酸二酐）具有出色的热性能（T5％d为377°C，Tg为358°C）和出色的介电性能（1kHz时为6.95），以及5.25Jcm-3的高放电能量密度和90％的充放电效率。主链和侧链工程的协同控制有效地赋予聚酰亚胺耐高温和高介电性能。
