Effect of graphene liquid crystal on dielectric properties of polydimethylsiloxane nanocomposites

Abstract Graphene can form a liquid crystal phase due to its anisotropic flake characteristics, it shows great potential in the field of high dielectric composites. In this paper, the graphene oxide sheets are grafted onto copolymer to uniformly disperse and maintain the liquid crystal state in a non-polar solvent, then the modified graphene oxide liquid crystal is transferred to polydimethylsiloxane. Graphene/polydimethylsiloxane nanocomposites are obtained by high temperature reduction and curing reactions. When the filler content is 4 wt%, the permittivity increases by 800% compared to pure polydimethylsiloxane. Therefore, graphene liquid crystal can significantly improve the dielectric properties of the nanocomposites than ordinary graphene, which provides a new method for preparing high dielectric properties composites.