The low permittivity of the polypropylene (PP) film has become a barrier for the further development of film capacitors with high energy storage density. An advanced strategy of the high-permittivity filler/polymer nanocomposite turns out to be a promising way of solving this problem. In this work, we coated ethylene propylene diene monomer (EPDM) as the shell on the surfaces of BaTiO₃ successfully to fabricate core-shell structural nanoparticles. The addition of surface rubberized BaTiO₃ into PP matrix promotes the permittivity to about 5.8, while the dielectric loss is barely changed as compared with PP itself. In addition, the elongation at break is as high as 364%, which is over 4 times higher than that of PP. The influences of shell thickness (3 nm, 5 nm and 7 nm) for the nanoparticles and hot-stretching process for the nanocomposite films were also carefully investigated, both of which greatly affected the properties of nanocomposites. Finally, the optimum breakdown strength as high as 370 MV/m is obtained, leading to a maximum energy density of 3.06 J/cm³, which can be attributed to both high breakdown strength and high permittivity of the core-shell structural BaTiO₃/PP nanocomposites.

聚丙烯（PP）薄膜的低介电常数已成为进一步发展具有高能量存储密度的薄膜电容器的障碍。高介电常数填料/聚合物纳米复合材料的先进策略被证明是解决该问题的一种有前途的方法。在这项工作中，我们成功地将乙丙二烯单体（EPDM）涂覆在BaTiO ₃表面作为壳，以制备核-壳结构纳米颗粒。表面橡胶化BaTiO _3的添加加入PP基体中，使介电常数提高到约5.8，而与PP本身相比，介电损耗几乎没有变化。此外，断裂伸长率高达364％，是PP的4倍以上。还仔细研究了壳厚度（3 nm，5 nm和7 nm）对纳米颗粒的影响以及纳米复合材料薄膜的热拉伸工艺，这两者都极大地影响了纳米复合材料的性能。最后，获得了高达370 MV / m的最佳击穿强度，从而导致最大能量密度为3.06 J / cm ³，这归因于核壳结构BaTiO ₃ /的高击穿强度和高介电常数。PP纳米复合材料。