Enhanced energy storage properties of all-polymer dielectrics by cross-linking

Polymer dielectrics with good energy storage properties are need for advanced electric devices. Herein, a new class of all organic dielectric cross-linkable polymers, poly(methyl methacrylate-glycidyl methacrylate) (P(MMA-GMA)) prepared by radical polymerization, is reported. A comprehensive investigation was conducted to examine the impact of the cross-linked monomer GMA content on the energy storage properties. The crosslinking significantly enhances the breakdown strength and suppresses the leakage currents. Consequently, the copolymer P(MMA-GMA) containing 7 mol% GMA exhibits a high discharge energy density of 16.5 J/cm3 at 750 MV/m, coupled with a high discharge efficiency of 82%. Even at an elevated temperature of 100 °C, it still possesses a good energy performance of a discharge energy density of 12.1 J/cm3 and a relatively high efficiency of 80.1% at 650 MV/m. This study offers a simple and effective approach to fabricating all-organic polymer dielectrics with good energy storage properties.