(649f) Understanding Self-Assembly of Polysulfamides from Molecular Dynamics Simulations Using Atomistically-Informed Coarse Grained Models

Polysulfamides are a new class of polymers that have the potential to serve as sustainable alternatives for commodity plastic polyurea due to similar chemical structures differing only in carbonyl groups (polyurea) and sulfamide groups (polysulfamide). Michaudel and coworkers have synthesized oligomers of polysulfamides that exhibit high thermal stability, adjustable glass transition temperatures with changing polymer backbone structure, and degradability in green conditions (Kulow et al., Chemical Science, 2020, 11, 7807-7812). Due to these desirable properties, there is significant motivation to create design-structure-property relationships. To achieve design-structure relationships, Jayaraman and coworkers (Wu et al., Macromolecules, 2023, 56, 13, 5033–5049) have used phenomenological coarse-grained (CG) models for polysulfamide and molecular dynamics (MD) simulations to link polysulfamide chain design to various features of the assembled structure. For example, they have calculated the strength of hydrogen bonding that is needed for chains to assemble and the positional and orientational order within the assembled chains as a function of the polysuflamide chain design. In this talk, we will present our current work to extend this past phenomenological CG model of polysulfamides to be atomistically-informed. We use atomistic MD simulations of polysulfamide chains to quantify relative spatial arrangement of hydrogen donor and acceptor species within sulfamide group and distributions of bonded angle and dihedral potentials between various groups of atoms; this information is then programmed into the ‘newer’ polysulfamide CG model. Then, using the same simulation protocol we compare the output of polysulfamide assembly MD simulations for the ‘older’ CG model of Wu et al. and atomistically informed ‘newer’ CG models. We observe that while the interaction strength of hydrogen-bonding that is needed for chains to assemble is higher for the ‘newer’ model than the ‘older’ model, overall trends in the structural arrangements with varying design is qualitatively the same between the two models.