Constructing molecularly-informed field theories from bottom-up coarse-graining: Rethinking how we engineer soft matter formulations*

Our work probes the behavior of complex, soft matter formulations–often comprised of macromolecules–by leveraging the strengths of both a particle and a field representation. Mesostructured polymeric solutions are difficult to study using traditional particle-explicit approaches (e.g., molecular dynamics) due to the disparate time and length scales, while the predictive capability of field theories is hampered by the need to specify emergent parameters (e.g., chi parameters) with nonobvious connections to molecular architecture. To overcome the weaknesses of both, we use small-scale, atomistic simulations to parameterize the statistical field theory models. Subsequently, field-theoretic simulations can probe behavior at larger length scales in these complex solutions efficiently while maintaining a rigorous connection to the underlying chemistries. This synergistic computational approach opens the door to explore–de-novo–the phase behavior of a wide variety of industrially relevant formulations, e.g., emulsions, coacervates, micelle assemblies, colloidal suspensions, and block copolymers. We demonstrate the capability of this approach by predicting the aqueous, PEO phase diagram, and the composition dependence of Pluronic® microphases.