Thermal enhancement by constructing ordered-orienting hybrid network with modified boron nitride, graphene and carbon nanotubes in epoxy composite coatings

A layer-by-layer ordered-orienting hybrid network was fabricated to enhance thermal conductivity by the size synergy of hydroxyl functionalized hexagonal boron nitride (h-BN), graphene (rGO) and carbon nanotubes (CNT). Firstly, modify the hexagonal boron nitride (h-BN) with tannic acid (TA) to improve its dispersibility and stability in EP coatings, and then mix the modified h-BN ([email protected]) with rGO and CNT to fabricate the composite coatings for thermal enhancement. When the volume of composite fillers is 46 %, the thermal conductivity of the [email protected]/EP composite coating is up to 5.65 W·(m−1 K−1), which is 22.6 times higher than that of the blank EP coating (0.25 W·(m−1 K−1)). The enhanced thermal conductivity is attributed to the impact of gravity and structural complementarity between [email protected], rGO and CNT, sequentially distributing homogeneously in EP matrix, and thus form ordered-orienting heat conduction path to reduce phonon scattering as well as interface thermal resistance. This desired thermal conductivity enhancement in composite coatings has practical applications for the cases of rapid heat-dissipation.