Achieving Temperature Transferable Coarse-Graining of Glass-Forming Polymers via Energy Renormalization

The bottom-up prediction of the properties of polymeric and glass-forming materials based on molecular dynamics simulation is a grand challenge in soft matter physics. Coarse-grained (CG) modeling is often employed to access greater spatiotemporal scales required for many applications. However, there is currently no temperature transferable and chemically specific coarse-graining method that allows for modeling of polymer dynamics over a wide temperature range. Here, we pragmatically address this issue by “correcting” for deviations in activation free energies that occur upon coarse-graining. In particular, we propose an energy-renormalization (ER) strategy to coarse-graining polymers based on relationships drawn from the Adam-Gibbs theory of glass formation, in conjunction with the localization model of relaxation. By testing different glass-forming materials ranging from fragile polymers to small molecules, we show that our ER approach can faithfully estimate the diffusive, segmental and glassy dynamics of the AA model over a large temperature range spanning from the Arrhenius melt to the non-equilibrium glassy states. Our proposed CG approach offers a promising strategy for developing thermodynamically consistent CG models with temperature transferability.