From Graphene Stabilized Emulsions to Foams

The unique electrical, thermal, and mechanical properties of graphene make it a perfect candidate for applications in graphene/graphite based polymer composites. Recently shown surface activity of the graphene sheets to oil-water interphase has opened a new path for design of graphene based polymeric materials. We use molecular dynamics simulations and theoretical techniques to elucidate factors responsible for surface activity and emulsion stabilization of 2D graphene sheets. In particular, we use large scale coarse-grained molecular dynamics simulations to study affinity of the 2D elastic sheets to interface between two immiscible solvent as a function of the sheet sizes and degree of substitution of atoms on the 2D sheets. The established envelop of parameters for sheets’ surface activity is used to model emulsion assembly and emulsion polymerization producing polymeric foams which cells are coated with 2D elastic sheets. The mechanical properties of foams are studied as a function of the crosslinking density, 2D-sheet/monomer affinity, and sheets bending rigidity. The results of the computer simulations are compared with corresponding experimental studies of the graphene stabilized emulsions and composite graphene/polymer foams.