Compressible Polymer Composites with Enhanced Dielectric Temperature Stability.

High-dielectric-constants polymer composites have broad application prospects in flexible electronics and electrostatic energy storage capacitors. Substantial enhancement in dielectric constants (ε r ) of polymer composites so far can only be obtained at high loading of nanofillers, resulting in high dielectric loss and high elastic modulus of polymer composites. Addressing the polarization shielding and the consequent polarization discontinuity at polymer/filler interfaces has been a long-standing challenge to achieve flexible polymer composite with high ε r . Herein, we propose and demonstrate a polymer composite with interconnected BaTiO 3 (BT) ceramic scaffold exhibiting a high ε r ∼ 210 at low BT volume fraction of ∼ 18 vol.%, approaching the upper limit predicted by the parallel model. By incorporating relaxor Ba(Zr x Ti 1-x )O 3 phase in BT scaffold, we further achieved excellent dielectric temperature stability with Δε r below ±10% within broad temperature range (25-140 °C). Moreover, the dielectric performances remain stable under compressive strain up to 80%. This work provides a facile approach to construct large-scale polymer composites with robust dielectric performance against changes in thermal and mechanical condition, which are promising for high-temperature applications in flexible electronics. This article is protected by copyright. All rights reserved.