Enhancing the Thermal Conductivity of Epoxy Resin by Grafting Melamine Onto Graphene to Suppress Longitudinal Thermal Conductivity

The lateral thermal conductivity of epoxy resin‐based composites was effectively optimized through a one‐step melamine‐grafted graphene approach. In this method, melamine is utilized to exfoliate graphite and facilitate grafting modification, thereby forming a modified filler with a three‐dimensional cross‐linked network structure. The structure was systematically characterized using XRD, FTIR, TEM, Raman, and XPS techniques before being incorporated into the EP matrix. Experimental results demonstrate that melamine grafting significantly enhances the dispersion of graphene within the EP, thereby establishing an efficient thermal conduction pathway. Consequently, the thermal conductivity of the composite reached 1.37 Wm −1 K −1 at a filler loading of 50 wt%, which represents an 805.88% increase compared to pure EP. This improvement can be attributed to the suppression of phonon scattering and the reduction of interfacial thermal resistance, both of which contribute to enhanced lateral thermal conductivity.