Dielectric, thermally conductive, and heat-resistant polyimide composite film filled with silver nanoparticle-modified hexagonal boron nitride

In this study, silver-polydopamine-hexagonal boron nitride (h-BN@Ag) particles were prepared using mussel chemistry and reducibility of catechol. The modified method was simple and eco-friendly. In addition, we prepared h-BN@Ag/polyimide (PI) composite films via in situ polymerization, the scraper method, and thermal imidization. Owing to the good dispersion of the h-BN@Ag filler particles in the PI matrix and the bridging role of the Ag nanoparticles, the thermal conductivities of the h-BN@Ag/PI composite films were higher than that of the pure PI film. The thermal conductivity of the h-BN@Ag/PI film with the filler content of 10 wt% was 0.382 W (m center dot K)(-1), which was 108% higher than that of pure PI films (0.184 W (m center dot K)(-1)). Furthermore, the composite films presented extremely low dielectric permittivity and loss tangent. Moreover, the heat resistance index of the composite films (304.6 degrees C) was higher than that of pure PI (294.3 degrees C). Thus, h-BN@Ag/PI composite films could be promising electronic packaging materials.