Systematic and Many-Chain-Simulation-Free Coarse Graining of Polymer Melts: Structure-based Coarse Graining of the Kremer-Grest Model

Our group recently proposed the systematic and simulation-free strategy for coarse graining of polymeric systems , where the well-developed polymer reference interaction site model (PRISM) theory, instead of the many-chain molecular simulation (MCMS), is used to obtain the structural and thermodynamic properties of both the original and coarse-grained (CG) systems. Our strategy is much faster than those using MCMS, thus effectively solving the transferability problem of coarse graining. It also avoids the problems caused by the finite-size effects and statistical uncertainties of MCMS, particularly for the original system, which are the reasons why its coarse graining is needed. Here we apply our strategy to the structure-based coarse graining of the well-known Kremer-Grest model for homopolymer melts, where the self-consistent PRISM theory is used to avoid the assumption of ideal-chain conformations in the original system. This paves the way to quantitatively applying our strategy to more realistic polymers and their multiscale modeling.