MD simulations of poly(lactic acid) chains of various molecular weights in melt

Molecular Dynamics (MD) Simulations of poly(lactic acid) (PLA) and its stereoisomers with different molecular weights in melt. The preparation of the systems is described elsewhere [1].

The dataset contains the production run for each system. The label PLLA denotes a system with only L-type of monomers, the label PDLA denotes a system with only D-type of monomers and the label copo100 is used for compolymer systems with 100 monomers per chain of both types. The percentage of D monomer in each copolymer is indicated in the label (55% and 16%). The production runs were performed at constant temperature of 500K and constant pressure of 1 atm. 

All files are in Gromacs format. The used force field parameters are summarized in PLAFF3.itp file in each directory.  The force field was based on ref[2] and it was modified to be able to simulate copolymer structures. Namely, the tabulated potential for the backbone dihedrals was replaced by the Ryckaert-Bellemans function, which has the same parameters for both types of monomers. In addition, a new atom type was created for the D-type of monomer, to be able to properly distinguish CMAP parameters for each type of monomer.

[1] Bačová, P; Harmandaris, V.; Molina,  S. I.; Macromolecules 2025 58 (16), 8572-8580, https://pubs.acs.org/doi/10.1021/acs.macromol.5c00918

[2] McAliley, J. H.; Bruce, D. A. Development of Force Field Parameters for Molecular Simulation of Polylactide. Journal of Chemical Theory and Computation 2011, 7, 3756–3767, DOI: 10.1021/ct200251x