The Processing of Epoxy/1 Wt% Graphene Nanocomposites: Effects of Ethanol on Flexural Properties

Abstract

Four different types of nanocomposites were successfully produced using solution casting technique. Graphene was dispersed in four different ethanol concentrations; 0g, 1g, 2.5g, and 5g. In general, it can be observed that ethanol is an excellent agent for 1 wt% graphene dispersed in the epoxy matrix. The maximum increase in flexural properties, impact strength and microhardness were observed in 1 wt% graphene dispersed in 1g ethanol. The flexural strength and modulus increased by 62% and 61% respectively. The highest impact strength was recorded for 1 wt% graphene dispersed with 1g ethanol, where an improvement of 9.5% was observed. The maximum Vickers microhardness was recorded to improve 3% compared to monolithic epoxy. SEM images revealed that graphene can impede the advancing cracks and significantly change the fracture mode from a straight fracture path to radially emanated path. It is worth to point out that if ethanol is not completely evaporated during processing, it can cause porosity which is unfavourable to the mechanical properties of the nanocomposites.