Compression-enhanced thermal conductivity of carbon loaded polymer composites

The miniaturization, integration and compatibilization of electronic devices dictate the need for efficient thermal management to prevent heat accumulation, which may reduce the operation speed and shorten their life time. Addressing this challenge requires the development of novel polymer-based composite materials with enhanced thermal conductivity. Here, we report a compression-based (25–250 bars) approach for the preparation of polymer composites loaded with carbon-based hybrid fillers, i.e., graphene nanoplatelets and graphite flakes. The carbon-based fillers contribute significantly to the thermal conductivity of the composite while boron nitride nanoparticles inhibit the electrical conductivity to avoid short circuits. An optimal thermal conductivity of 27.5 W (m K)⁻¹ is obtained for the compressed system (measured under atmospheric pressure) for epoxy polymer loaded with 30 wt% graphene nanoplatelets and 40 wt% graphite flakes compared to 0.2 W (m K)⁻¹ of the neat thermoset polymer.