Graphene in epoxy system: Dispersion, preparation and reinforcement effect

Epoxy is one of the most adaptable and widely sold high performance material in the world because of its excellent mechanical properties, thermal stability, chemical and corrosion resistance, low shrinkage, low cost, and ease of processing, etc. Graphene shows good potential for the fabrication of high performance polymer nanocomposites because of its unique planar structure and its superlative mechanical properties, thermal conductivity and excellent electrical conductivity. The layered structure allows a large surface contact area with the matrix and thus leads to improvements in the properties. This work aims at exploiting the potential use of graphene as a filler to reinforce epoxy matrix and the preparation of homogeneously dispersed epoxy/graphene nanocomposites. To explore the maximum property enhancement of graphene in epoxy, dispersion is the key factor. However, in the preparation of epoxy/graphene nanocomposites, there still exist some challenges. One of the largest obstacles it that graphene tends to reagglomerate in liquid epoxy, which is due to the strong van der Waals force on the graphene surface. If not properly dispersed, the agglomerated graphene will act as a defect within the matrix and consequently lower the properties of the nanocomposites. Therefore, the dispersion of graphene and the processing techniques should be studied. In this work, epoxy/graphene nanocomposites had been made by different processing techniques. Different characterization methods had been applied to evaluate the reinforcement effect. By end of this work, graphene dispersion techniques and sample preparation methods have been optimized. Epoxy/graphene nanocomposites have been prepared with enhanced properties