Processing of epoxy/ graphene nanocomposites

Graphene can significantly improve physical properties of epoxy at extremely low loading when incorporated appropriately. However, in practical terms, graphene is not suitable to disperse in epoxy just by simple mixing, which is due to graphene’s pronounced tendency to reaggregate in the matrix due to the strong van der Waals force between separately dispersed graphene sheets. In order to substitute traditional epoxy reinforcements with graphene, there are still some issues like dispersion, homogenization, and reaggregation. Therefore, the preparation of epoxy/graphene nanocomposites affects strongly to the final properties of nanocomposites. In this work, graphene bundles have been dispersed in two-component epoxy system by bath sonication. Dispersion state and reaggregation behaviour of graphene in this system have been studied. Light transmittance in ultraviolet-visible spectroscopy has been used to quantify the reaggregation by a series of controlled experiments