Polyimide (PI), a kind of polymer with excellent heat resistance, processing, mechanical and electrical insulation performance, stands out as a prime candidate for advanced dielectric energy storage materials. However, the low dielectric constant of PI has hindered its broader development, requiring dielectric modification. In order to increase the dielectric constant of PI, PI with a polar trans-cyclohexane structure was synthesized and characterized and then reinforced with nano-C@BT-fibers to produce a novel nanofiber reinforced PI film. Experimental results demonstrate that polar trans-cyclohexane enables pure PI films to achieve a dielectric constant of 8.89 at 100 Hz. Meanwhile, the dielectric constant of C@BT-fibers/modified PI composite films was indeed increased up to 39.48 at 100 Hz and the energy storage density increases to 1.028 J cm⁻³ with only 1.0 wt% addition content of C@BT-fibers, increased by 117.3% compared with that of pure PI (0.473 J cm⁻³).

中文翻译：

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新型纳米C@BaTiO3纤维/极性反式环己烷改性聚酰亚胺复合薄膜，具有增强的介电性能和储能密度


聚酰亚胺 （PI） 是一种具有优异耐热性、加工性、机械和电气绝缘性能的聚合物，是先进介电储能材料的首选候选材料。然而，PI 的低介电常数阻碍了其更广泛的发展，需要介电改性。为了提高PI的介电常数，合成了具有极性反式环己烷结构的PI并进行了表征，然后用纳米C@BT纤维增强，制备了一种新型纳米纤维增强PI膜。实验结果表明，极性反式环己烷使纯 PI 薄膜在 100 Hz 时达到 8.89 的介电常数。同时，C@BT纤维/改性 PI 复合薄膜的介电常数在 100 Hz 时确实增加到了 39.48，储能密度增加到 1.028 J ^cm-3，C@BT纤维的添加量仅为 1.0 wt%，与纯 PI （0.473 J ^cm-3） 相比增加了 117.3%。