Calculation of specific heat of polymers using molecular dynamics simulations

Precise evaluation of the heat capacity at constant pressure (C-p) of polymers during rapid heating and cooling is required to predict and optimize the performance of polymer products after laser-assisted manufacturing processes. However, currently available experimental methods are not capable of determining C-p at rapid temperature fluctuations. Molecular Dynamics (MD) simulations could be useful to evaluate C-p under such conditions. In order to determine the efficacy of MD simulation, C-p at the room temperature of various well-studied polymers (polyethylene, polyethylene terephthalate, polypropylene, polystyrene, polyvinyl chloride, and polytetrafluoroethylene) were computed with the MD simulations using General Amber Force Field (GAFF) potentials. The simulated C-p values for these polymers were found to be higher than experimental values. Possible reasons for the disparity in C-p values are discussed, and suggestions for extracting accurate C-p values are provided.