Recyclable and Thermally Stable Dielectric Elastomer Composites with Desirable Dielectric Properties Based on Silyl Ether Linkages

The rapid advancement of soft robotics and smart electronics imposes more demanding requirements on dielectric elastomers (DEs), requiring high dielectric performance at elevated temperatures and sustainable lifecycle solutions, which is a great challenge unmet by conventional dynamic bonds. Herein, we propose a composite featuring a dynamic silyl ether-based network dispersed with aluminum hydroxide decorated reduced graphene oxide (Al(OH) 3 @RGO) hybrid fillers, which reconciles the inherent conflict among high dielectric performance, excellent thermal stability, and efficient reprocessability in DEs for the first time. The anchored aluminum hydroxide coating promotes the dispersion of reduced graphene oxide, substantially enhancing the dielectric properties of the composites. The optimized PDMS/Al(OH) 3 @RGO-1.0% exhibits a peak electromechanical sensitivity of ∼10.35 MPa –1 at 100 Hz and retains most of its mechanical properties and nearly all of the dielectric constant after three reprocessing cycles. Moreover, the composite shows outstanding thermal stability, with a T 50 (the temperature at 50% weight loss) as high as 522 °C, and maintains nearly complete mechanical and dielectric integrity after thermal-oxidative aging for 24 h at 150 °C. Remarkably, even at 150 °C, it preserves a high dielectric constant of ∼9.93 at 100 Hz, demonstrating exceptional high-temperature dielectric performance. This work provides an effective strategy for fabricating recyclable high-performance dielectric elastomer composites suitable for high-temperature environments.