Molecular Dynamics Simulations of Thermal Properties of Polymer Composites Enhanced by Cross-Linked Graphene Sheets

Molecular models of pristine, functionalized and cross-linked graphene sheet/polymer composites are developed. Temperature cooling processes are conducted to examine the improvement of glass transition temperature of cross-linked graphene sheet/polymer composites using molecular dynamics simulations. The results show that increases of about 12.2% and 8.9% in the glass transition temperature of cross-linked graphene sheet/polymer composites are obtained, respectively, than those of the pristine and functionalized graphene sheet/polymer composites. In order to reveal the enhanced thermal properties from atomic views, the interfacial interaction energy and radius distribution function between the graphene sheets and the polymer matrix, the mean square displacement variations and the free volume of polymer composites are examined and discussed.