Synergistic effects on the enhancement of thermal conductive properties of thermal greases

Efficient heat dissipation from electronic devices with high-degree integration and high-power density has become an urgent and complex problem. We report here novel thermal greases with an enhanced thermal conductivity using graphene flakes (GFs), hexagonal boron nitride (h-BN), and hydroxypropyl cellulose (HPC) as fillers. The obtained GF/h-BN/HPC thermal grease at 23 vol % h-BN loading exhibits a thermal conductivity enhancement 555%, compared with the pure PDMS matrix, and also about 50, 169, and 115% higher than that with GF/h-BN, h-BN/HPC and h-BN as the filler for the thermal grease, respectively. We attribute it to the synergistic effects among GF, h-BN, and HPC, due to the formation of thermally conductive networks. This study provides a strategy for preparing thermal greases for thermal management applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47726.