Silica Nanoparticles Reinforced Ionogel as Nonvolatile and Stretchable Conductors

Ionogels combine the advantages of being conductive, stretchable, transparent and nonvolatile, which makes them suitable to be applied as conductors for flexible electronic devices. In this paper, a series of ionogels based on 1-ethyl-3-methylimidazolium ethyl-sulfate ([C₂mim][EtSO₄]) and polyacrylic networks were prepared. Silica nanoparticles (SNPs) were dispersed into the ionogel matrix to enhance its mechanical properties. The thermal, mechanical and electrical properties of the ionogels with various contents of crosslinking agents and SNPs were studied. The results show that a small amount of SNP doping just increases the breaking strain/stress and the nonvolatility of ionogels, as well as maintaining adequate conductivity and a high degree of transparency. Furthermore, the experimental results demonstrate that SNP-reinforced ionogels can be applied as conductors for dielectric elastomer actuators and stretchable wires, as well as for signal transmission.