Heat tolerant epoxy-amine functionalized graphene oxide composites for insulation applications

摘要

Heat tolerant polymers are in much demand in electrical, structural, and electronic packaging applications. This article reports on a comparison of epoxy composites reinforced with graphene oxide (GO) and amine-functionalized GO (AGO) on their dielectric properties and adhesive strength in the temperature range of 30-110 degrees C. GO was synthesized using the modified Hummers method and functionalized with amine functional group using hexamethylenediamine (HMDA) and confirmed by Raman spectroscopy. Various filler concentrations (0.2-0.6 wt.%) of GO/AGO epoxy nanocomposites were prepared using the solution blending method and analyzed using a dynamic mechanical analyzer (DMA), impedance spectroscopy, and the single lap shear (SLS) test. Studies showed AGO reinforced epoxy composites outperforming than neat epoxy and GO-epoxy composites for all the compositions. The optimum concentration of AGO was found to be 0.4 wt.% based on its relative permittivity, dielectric loss and retention of adhesive strength up to 90 degrees C. The percentage of cohesive area on the fractured surface of SLS tested AGO was similar to 1.4 and similar to 3 times better than that of GO-epoxy and neat epoxy, respectively. The higher strength retention of AGO-epoxy nanocomposites is suitable for high-temperature insulation applications as adhesive coatings.