All‐organic polymer blend dielectrics of poly (arylene ether urea) and polyimide: Toward high energy density and high temperature applications

Abstract The development of high‐performance dielectric films with high energy density and temperature stability is extremely desired for modern electronics and power systems. Herein, a simple and low‐cost approach is proposed to fabricate all‐organic blend films prepared from poly (arylene ether urea) (PEEU) and polyimide (PI) via solution casting and thermal imidization process. The incorporation of PEEU in PI matrix significantly improved dielectric breakdown strength and dielectric constant of PI. More precisely, blend film with 15 wt% PEEU exhibited highest energy density 5.14 J/cm 3 at 495.65 MV/m, with enhanced dielectric constant of 4.73 and very low dissipation factor of 0.299%. Furthermore, the dielectric properties of the PEEU/PI blend displayed wonderful temperature stability in the range of − 50–+ 250°C, and great frequency stability between 10 and 10 6 Hz. The blend film also exhibited excellent heat resistance and presented valuable potential in thin film capacitors for high voltage direct current system.