Enhanced Electromechanical Property of Silicone Elastomer Composites Containing TiO₂@SiO₂ Core-Shell...

Dielectric elastomer (DE) is one type of promising field-activated electroactive polymer. However, its significant electromechanical actuated properties are always obtained under a giant electric voltage, which greatly restricts the potential applications of DE. In the present work, the well-constructed core-shell TiO₂@SiO₂ nanoparticles were fabricated by using the classical Stöber method. A series of TiO₂@SiO₂ nano-architectures-filled polydimethylsiloxane (PDMS) composites were prepared via solution blending and compression-molding procedures. Benefiting from the additional SiO₂ shell, both the interfacial compatibility between fillers and matrix and core-shell interfacial interaction can be improved. The TiO₂@SiO₂/PDMS nanocomposites exhibit a significantly enhanced in-plane actuated strain of 6.08% under a low electric field of 30 V·μm^-1 at 16 vol.% TiO₂@SiO₂ addition, which is 180% higher than that of neat PDMS. The experimental results reveal that the well-designed core-shell structure can play an important role in both improving the electromechanical actuated property and maintaining a good flexibility of DE composites. This research provides a promising approach for the design of the novel composites with advanced low-field actuated electromechanical property in next generation DE systems.