An atomistic view of heat propagation from graphene to polyether ether ketone (PEEK)

Abstract

Graphene is a two-dimensional form of carbon that has shown outstanding potential as an additive to polymer composites. Polyether ether ketone (PEEK) is a thermoplastic polymer that has been used extensively in industrial applications due to its high temperature stability, as well as other mechanical and chemical properties. In this study, we model a scenario where the graphene in a PEEK-graphene composite is heated, and then observe the response of PEEK polymer chains to the heat generated by graphene. Studying heat transfer from graphene to PEEK, as well as the effect of changes in the local chemistry at the interface between both materials, can improve the understanding of the performance of high-temperature graphene-PEEK. Using molecular dynamics and ab initio simulations, it is determined that as graphene in the composite is heated, the extent of the interfacial region between the two components changes. These changes affect the range of interactions at the interface as well as the efficiency of heat transfer. The number of graphene layers appears to play a significant role in the change in the interfacial region. Unlike monolayer and hexalayer graphene-PEEK configurations, bilayer graphene-PEEK configuration shows a decrease in the extent of the interfacial region at low temperatures, an indication of a more efficient heat transfer. The addition of approximately 5% hydroxyl functionalization of the surface of the graphene translated into a significant increase in the heat transfer.