Polymer composites with high dielectric constant and thermal stability have shown great potential applications in the fields relating to the energy storage. Herein, core-shell structured [email protected]₃ ([email protected]) nanoparticles were fabricated via in-situ polymerization of poly(amic acid) (PAA) and the following thermal imidization, then utilized as fillers to prepare PI composites. Increased dielectric constant with suppressed dielectric loss, and enhanced energy density as well as heat resistance were simultaneously realized due to the presence of PI shell between BT nanoparticles and PI matrix. The dielectric constant of [email protected]/PI composites with 55 wt% fillers increased to 15.0 at 100 Hz, while the dielectric loss kept at low value of 0.0034, companied by a high energy density of 1.32 J·cm⁻³, which was 2.09 times higher than the pristine PI. Moreover, the temperature at 10 wt% weight loss reached 619°C, demonstrating the excellent thermostability of [email protected]/PI composites. In addition, [email protected]/PI composites exhibited improved breakdown strength and toughness as compared with the BT/PI composites due to the well dispersion of [email protected] nanofillers and the improved interfacial interactions between nanofillers and polymer matrix. These results provide useful information for the structural design of high-temperature dielectric materials.

具有高介电常数和热稳定性的聚合物复合材料在与储能相关的领域中显示出巨大的潜在应用。在此，采用核心外壳结构[受电子邮件保护] ₃通过聚（酰胺酸）（PAA）的原位聚合和以下热酰亚胺化作用制备了[[受电子邮件保护]）纳米颗粒，然后将其用作填料以制备PI复合材料。由于在BT纳米颗粒和PI基质之间存在PI壳层，因此同时实现了介电常数的增加和介电损耗的抑制，以及更高的能量密度和耐热性。含55 wt％填料的[受电子邮件保护] / PI复合材料的介电常数在100 Hz下增加至15.0，而介电损耗则保持在0.0034的较低值，同时具有1.32 J·cm ^-3的高能量密度，是原始PI的2.09倍。此外，失重10 wt％时的温度达到619°C，这表明[电子邮件保护] / PI复合材料具有出色的热稳定性。另外，由于[受电子邮件保护的]纳米填料的良好分散以及纳米填料与聚合物基质之间的界面相互作用的改善，与BT / PI复合材料相比，[受电子邮件保护的] / PI复合材料表现出更高的击穿强度和韧性。这些结果为高温介电材料的结构设计提供了有用的信息。