The molecular dynamics study of atomic compound and functional groups effects on the atomic/thermal behavior of polyethylene glycol/graphite-based matrixes

In this study, Molecular Dynamics (MD) simulations were conducted for a thermophysical analysis of polyethylene glycol (PEG)/graphite (G), PEG/expanded graphite (EG), PEG/graphite oxide nanoparticle (GONP), and PEG/reduced GONP (rGONP) nanocomposites as shape stabilized phase change materials (SSPCMs). Specifically, thorough information regarding the PEG penetration in diverse graphite atomic structures and thermal conductivity (TC) under varied temperatures was investigated. The results of equilibrium MD simulations showed that PEG atoms penetration was increased at first and then remained constant with step time. Further, non equilibrium MD simulations revealed that the thermal conduction could be improved by introducing graphite whit nanostructure and a low amount of oxygen-containing functional groups (relative to rGONP). So that the TC measured for PEG/rGONP is about 18% higher than that of PEG/GONP. We expect MD outcomes of this research could benefit the future development of SSPCMs with high TC.