Electrical and Mechanical Properties of the Dielectric Capacitor Film Based on Polyvinylidene Fluoride and Aromatic Polythiourea

To obtain the flexible dielectric material suitable for mass produced supercapacitor, blend films based on polyvinylidene fluoride (PVDF) and aromatic polythiourea (ArPTU) were prepared by solution casting. We found that the PVDF/ArPTU blend film is a good energy storage material for capacitors with high breakdown strength and low loss at high filed. The breakdown field of PVDF/ArPTU (90/10) film is more than 700 MV/m, and the maximum released energy density is up to 11 J/cm3 with discharging efficiency above 80%. We also proved that the mechanical property of blend films is much better than that of pure ArPTU film, and the toughness and softness are close to the level of PVDF film. The blend film based on PVDF and ArPTU is a flexible dielectric material in the manufacture of supercapacitor.