High Thermal Conductivity Polyelectrolyte Nanocomposite Electrical Insulation Thin Films

作者：Ethan T. Iverson, Hudson Legendre, S. Chakravarty, Shiyu Zhang, Sarah G. Fisher, Dallin L. Smith, Kendra Schmieg, Yanling Ge, Dion S. Antao, Patrick J. Shamberger, Jaime C. Grunlan · 发表于：Advanced Functional Materials · 年份：2024 · DOI：10.1002/adfm.202420355 · 被引用次数：14 · 研究领域：Thermal properties of materials、Dielectric materials and actuators、Advanced Battery Materials and Technologies

Abstract High‐power electronics require thin, conformal insulation that resists dielectric breakdown, while promoting removal of heat from the device. Recently, polyelectrolytes have shown promise in creating dielectric thin films, but their thermal conductivity remains relatively low (<1 W m −1 K −1 ). In this work, the layer‐by‐layer (LbL) assembly of polyethylenimine, mica clay, poly(acrylic acid), and hexagonal boron nitride is exploited to create a thin film dielectric material with relatively high thermal conductivity (through‐plane thermal conductivity of 1.87 ± 0.03 W m −1 K −1 ) and strong electrical insulation (breakdown strength of 152 kV mm −1 ). High thermal conductivity is obtained due to mica and hexagonal boron nitride nanoplatelets stretching through multiple layers. The performance benefits of this nanocomposite are demonstrated with a partial motor, where the nanocomposite greatly reduces the peak temperature of the motor when compared to state‐of‐the‐art polyimide insulation. This remarkable combination of thermal conductivity and dielectric breakdown strength represents a significant advancement in the electrical and thermal protection of high voltage devices.