Since the discovery and isolation, graphene has become a sought-after 2D material to incorporate into polymers, batteries, and capacitors. However, an inherent challenge for graphene applications has always been its production. Exfoliation of bulk graphite to graphene, using current methods, requires large inputs of energy or the use of hazardous and harmful chemicals. The method developed in our lab, solvent interfacial trapping method (SITM), seeks to eliminate some of those constraints by using the innate dislike that graphene has for aqueous or oil phases. By placing graphite at the interface between the immiscible liquids, such as, water/oil interface, the graphite spontaneously spreads, exfoliating in order to stabilize the interface. By replacing the oil layer of a graphene stabilized emulsion with a monomer that can be polymerized, a composite foam with a 3D percolating network of graphene spheres can be obtained. To study the formation of this emulsion template, we added an aqueous radical scavenger to the system to inhibit the polymerization at the interface between graphene and the oil phase. Minimizing the polymerization occurring at the graphene stabilized monomer/water interface resulted in a change in the morphology. Instead of the coalescence observed in the control samples, the poly(HIPE)s with ascorbic acid contained lower average sphere sizes, but with a higher overall size dispersity, suggesting Oswald ripening. The inhibition of the interfacial polymer allows for movement of the aqueous phase held within the graphene spheres from smaller to larger water droplets prior to the full solidification of the interstitial polymer.

Activation of Oswald ripening mechanism in graphene stabilized polymerized high internal phase emulsions

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.