Electromechanical characterization of flexible and highly conducting multilayer graphene/polydimethylsiloxane composite paper

Multilayer graphene (MLG)/polydimethylsiloxane (PDMS) composite has been prepared by infiltrating free-standing MLG paper, obtained through the vacuum filtration of MLG-suspension using a nanoporous filter, with PDMS prepolymer. Electrical properties of both free-standing MLG paper and MLG/PDMS composite paper were investigated by four-point probe measurements. The obtained results show that the annealed MLG paper is characterized by a sheet resistance of ~ 0,69 Ω/□ which does not increase significantly with polymer infiltration. Moreover the electromechanical behaviour of the composite paper has been investigated experimentally by measuring the DC electrical resistance of the produced specimen during a tensile strength test. It results that the breaking of composite paper occurs at ~ 80% strain, like for the neat polymer, but with a more than doubled applied load. Furthermore, it is noted that for strain smaller than ~ 10%, the electrical resistance of MLG/PDMS composite paper is nearly constant.