Fabrication of stretchable and conductive polymer nanocomposites based on interconnected graphene aerogel

Abstract The construction of advanced nanocomposite structures is a principal strategy to realize the electrical and mechanical functionalities of graphene for flexible electronic applications. Herein, two types of conductive and stretchable networks were fabricated by incorporation of polyurethane and silicone elastomers into highly porous and interconnected graphene gels. The layer-by-layer assembly of the graphene aerogel was solution-processable at room temperature, which offers a wide processing window for the solvent engineering and infiltration of polymers to improve wettability. Effects of graphene-polymer interfacial properties were investigated by their cross-sectional morphologies and viscoelastic analyses to elucidate the packing density, dispersion state, surface chemistry, polymer distribution and chain mobility. The polymer-infiltrated graphene network exhibited a high conductivity of ~100 S/m at a low filler content of 0.8 wt%. Given the excellent structural integrity, the graphene composites demonstrated unique electrical properties under stretching and bending conditions. Particularly, a maximum conductivity of 47 S/m was achieved under 50% tensile strain and the resistance deviation was less than 5% upon 500 bending cycles. The proposed design of graphene architecture and polymer infiltration techniques serve to pave the way for the next-level development of graphene electronics.