Enhanced High‐Temperature Dielectric Properties of Poly(aryl ether sulfone)/BaTiO 3 Nanocomposites via Constructing Chemical Crosslinked Networks

Heat‐resistant and crosslinked polymers/ceramic composites have been prepared and investigated for enhancing high‐temperature dielectric properties to adapt the development of advanced electric and electronic systems. Here, a series of crosslinkable heat‐resistant poly(arylene ether sulfone)s (DPAES) with large dipole units of −SO 2 − are designed and synthesized as matrix, which are blended with BaTiO 3 (BT) nanoparticles to fabricate crosslinked polymer composites for boosting high‐temperature dielectric properties. The results show that BT/c‐DPAES possess great dielectric stability at measured frequency and temperature. Meanwhile, the discharged energy density and efficiency of BT/c‐DPAES composites are higher than that of BT/DPAES at high temperatures, e.g., 10 vol% BT/c‐DPAES has a discharged energy density of 1.7 J cm −3 and efficiency of 73%, increasing by 42% and 128% in contrast to BT/DPAES, respectively. The enhanced high‐temperature energy storage properties can be attributed to the construction of a crosslinked polymer network, reducing leakage current density of composites.