Macrocycle-based host-guest interactions improving electrical energy storage capability of all-organic dielectric composites

Abstract

Polymer films capacitors are widely used in the electrical and electronic fields, and much effort has been devoted to exploiting the high temperature resistant polymer dielectrics with superior discharged energy density (U_d) and efficiency (η) in harsh environments. The addition of organic molecular fillers is good way to improve the energy storage properties of dielectric polymers. In this work, for the first time, the host organic filler (methyl β-cyclodextrin, M-β-CD) is embedded into the guested polynorbornene dielectrics containing amantadine side-chain (PATMD). All-organic polymeric dielectric composites (M-β-CD/PATMD) is obtained based on the host-guest interaction between PATMD matrix and M-β-CD filler. The experiment results showed that the introduction of host filler can obviously enhance the U_d and η at high temperature and high field because inclusion complex can simultaneously increase thermal performance and trap depth. The maximum U_d of 0.1 wt% M-β-CD/PATMD is 7.4 J/cm², maintaining the η of above 90 %. Importantly, at 150 °C and 200 °C, the largest U_d of 4.3 J/cm² and 3.6 J/cm² is achieved respectively, and the corresponding η is 80 % and 74 %, which is both much higher than that of pure PATMD. This work proves that the cyclodextrin-based host-guest design method is a good effective strategy for the preparation of high performance polymer dielectrics.