High-k, UV curable polymer composites with low dielectric loss and high breakdown strength were prepared. Fluorosilane coupling agent (FAS-17) was adopted to modify the surface of BaTiO₃ (BT) nanoparticles. Characterization results of UV-cured composites filled with BT@FAS-17 particles indicate that the dielectric loss is dramatically decreased and the breakdown strength is significantly improved, especially for the highly-loaded composites. The underlying mechanism of these performance improvements is further studied by temperature-dependent dielectric spectra, thermally stimulated depolarization current experiments as well as the first-principle simulation, which suggest that H-bonding and additional interfacial traps introduced by FAS-17 account for the enhanced dielectric properties. This work proposes a facile and efficient technique for the fabrication of photosensitive high-k composites with low dielectric loss and high breakdown strength, which is suitable for a variety of advanced applications such as energy storage, functionally graded dielectric materials and 3D-printing fabrication of dielectrics.

制备了具有低介电损耗和高击穿强度的高k紫外线可固化聚合物复合材料。采用氟硅烷偶联剂（FAS-17）修饰BaTiO ₃表面（BT）纳米粒子。掺有BT @ FAS-17颗粒的UV固化复合材料的表征结果表明，介电损耗显着降低，击穿强度显着提高，特别是对于高负载复合材料而言。通过与温度相关的介电谱，热激发的去极化电流实验以及第一性原理模拟，进一步研究了这些性能改善的潜在机理，这表明FAS-17引入的H键和其他界面陷阱是增强的介电性能。这项工作为光敏高k的制造提出了一种简便而有效的技术。 具有低介电损耗和高击穿强度的复合材料，适用于各种高级应用，例如储能，功能梯度介电材料和介电体的3D打印制造。