High permittivity nanocomposites fabricated from electrospun polyimide/BaTiO3 hybrid nanofibers

High dielectric permittivity, good mechanical properties, and excellent thermal stability are highly desired for the dielectric materials used in the embedded capacitors and energy‐storage devices. This study reports polyimide (PI)/barium titanate (BaTiO₃) nanocomposites fabricated from electrospun PI/BaTiO₃ hybrid nanofibers. The PI/BaTiO₃ nanocomposites were investigated using Fourier transform infrared spectroscopy, scanning electron microscope, transmission electron microscope, thermal gravimetric analysis, an electromechanical testing machine, a LCR meter and an electric breakdown strength tester. The results showed that BaTiO₃ fillers were uniformly dispersed up to 50 vol% in PI matrix. The dielectric permittivity of the composite (50 vol% BaTiO₃) was 29.66 with a dielectric loss of 0.009 at 1 kHz and room temperature. The dielectric permittivity showed a very small dependence on temperature (up to 150°C) and frequency (100 Hz–100 kHz). The nanocomposites also showed high thermal stability and good mechanical properties. The PI/BaTiO₃ nanocomposites will be a promising candidate for uses in embedded capacitors, especially in high temperature circumstance. POLYM. COMPOS., 37:794–801, 2016. © 2014 Society of Plastics Engineers