Evaluation of Thermo-Mechanical Properties of Carbon/Epoxy Amino-Functionalized Graphene Nanoplatelet Composite

A systematic study has been conducted on processing and characterizing of carbon fiber reinforced epoxy polymer (CFRP) composites to enhance its viscoelastic and thermal properties through the integration of optimized amount of amino-functionalized (NH2-GNP) graphene nanoplatelet (GNP). Epoxy resin, EPON 828, was modified infusing 0.1, 0.2, 0.3, 0.4, and 0.5 wt % of NH2-GNP as a nano reinforcing agent. The GNP was infused into EPON 828 resin using a high intensity ultrasonic processor followed by a three-roll milling for better dispersion. Epikure 3223 curing agent was then added to the modified resin and mixed using a high-speed mechanical stirrer. The nanophase epoxy was then used to fabricate CFRP nanocomposites using the compression molding process. Dynamic mechanical analysis (DMA) and thermomechanical analysis (TMA) were performed to analyze the viscoelastic and thermal performances of these composites. In all cases, the 0.4 wt% GNP-infused epoxy nanocomposite exhibited the best properties. The 0.4 wt % GNP modified carbon fiber/epoxy composite demonstrated 19% and 23% improvement in storage modulus and loss modulus, respectively. Moreover, there were about 13% and 28% reduction in the coefficient of thermal expansion before and after glass transition temperature, respectively. Glass transition temperature and crosslink-density were also observed to be enhanced for the 0.4 wt % loading due to better interfacial interaction and effective load transfer between the NH2-GNP and the epoxy resin.