Large-scale and low-cost production of graphene nanosheets-based epoxy nanocomposites with latent catalyst to enhance thermal conductivity for electronic encapsulation

摘要

High density and high-power integrated circuits require fast heat dissipation electronic encapsulation martials. epoxy composites are one of the most common materials in packaging areas. However, epoxy have low thermal conductivity value. Graphene nanosheets are the good option to combine with epoxy to enhance the thermal conductivity due to its high thermal conductivity value (3000 - 5000 W/mK). In this paper, graphene nanosheets fabricated by liquid exfoliation of graphite powders were proposed. We combined low-energy ball milling and sonication methods to produce graphene nanosheets on a large scale. The surfactant sodium dodecyl sulfate (SDS) has been used as the stabilizer to prevent graphene nanosheets from aggregating. Additionally, the latent catalyst was used in epoxy composites during the curing process. It was obviously that latent catalyst plays the role of accelerator in the epoxy curing at specific curing temperature, which could provide effective control of curing process by heating. Also, it provided better storage ability for epoxy composites. The graphene-epoxy composites achieved higher thermal conductivity which was enhanced 225% compare to pure epoxy, which has the potential to be applied in heat management materials of electronic encapsulation.