Enhancement of dielectric properties of acrylic resin elastomer-based composites with SiO₂ loaded carbon nanotubes

The inherent balance between dielectric constant and loss restricts the actual usage of dielectric elastomer actuators with high actuation strains, proposing a method that can break this trade-off has been an urgent query. In this work, silica-loaded carbon nanotubes (called SiO2@CNT) were prepared as dopants for acrylic resin elastomers (abbreviated as ARE) using the sol-gel method, and the obtained SiO2@CNT/ARE composites reached a dielectric constant of 282.5 at 100 Hz at a filler content of 3.22 vol%, which is 86 times higher than that of the pure ARE, whereas the dielectric loss remains at 0.17. The equilibrium between dielectric constant and loss is broken mainly based on the loading of SiO(2)which inhibits the formation of carbon nanotube conductive network and concurrently reinforces the compatibility of the filler with ARE. Such a design offers a generalizable strategy for the subsequent preparation of polymer-based composite films with excellent dielectric properties.