Multiscale modeling of thermomechanical properties of stereoregular polymers

Temperature-Transferable Coarse-Grained Models for Volumetric Properties of Poly(lactic Acid)

“…Generally, coarse graining makes the potentials smooth and thus yields the lower T g , which applies to those in most of the previous studies. In my previous studies, ,,,,,− in particular, the nonbonded CG potentials were parametrized using the same method, and the simulated T g was near to or lower than the experimental value. However, this cannot explain the current result that the CG simulations lead to the higher T g than the AA simulations, implying a different mechanism.…”

“…Typically, each molecular segment or monomer of a polymer chain containing four heavy atoms on average is mapped as one CG bead, and the interaction site is placed at the position of some true atom, the center of mass (COM) or center of geometry (COG) for these atoms. Seldom, the interaction site was also placed at the center of charge (COC), which was found to be superior to other alternatives in some cases. − As the basic logic is similar to the AA force field, some assumptions are made for CG potentials: the total potential energy can be decomposed into two parts, bonded and nonbonded; the bonded potential energy can be separated into three items, bond, angle, and dihedral, which are applied to 1–2, 1–3, and 1–4 CG beads along the same chain, respectively. While the CG dihedral potentials are excluded in some cases, the CG bonded potentials beyond 1–4 are introduced in other cases .…”