The Polymer Society of Korea

Abstract

Accurately reproducing the mechanical properties of an all-atom (AA) model within a coarse-grained (CG) model requires the appropriate time scaling factor and level of coarse-graining. Since CG models have smoother potential energy surfaces, they exhibit faster dynamics than AA models. Although the Mean Square Displacement (MSD) trends were consistent across models , a significant discrepancy emerged after applying time scaling to construct stress curves. All CG models consistently underestimated the stress compared to the AA model, failing to accurately reproduce the mechanical behavior. This discrepancy arises because the energy dissipation mechanisms differ.  In AA models, the dominant mechanism transitions from inter-chain non-bonded interactions to intra-chain dihedral motion during deformation. The simplification of such intramolecular interactions in CG models fundamentally alters this energy pathway, leading to the inaccurate prediction of mechanical properties.