Multi-scale analysis of thermoelastic properties of graphene foam/PDMS composites

In macroscopic applications, the production of graphene foam (GF) can be an attractive way to utilize the combined advantages of graphene sheets and porous materials. The porosity level significantly affects mechanical and thermal properties by changing the specific surface area. In this study, a multi-scale method is used to calculate the coefficient of thermal expansion (CTE) and heat capacity of GF/polymer composites. Molecular dynamics have calculated the properties of 3D GFs. In particular, four types of GF with increasing mass density and decreasing porosity are investigated. The thermoelastic properties are calculated as temperature-dependent for all groups of GF. Mechanics of structure genome (MSG) based on Carrera unified formulation (CUF) is used to calculate the effective properties of the GF/polymer composites. It was found that the composite consisting of GF with the highest density and lowest porosity has the minimum CTE. Also, the heat capacity of the composite depends not only on the heat capacity of the components but also on their Young modulus, CTE, and geometry.