Field-theoretic simulations of core-shell bottlebrush copolymers

The unique structure of bottlebrush polymers, featuring a linear polymer backbone grafted densely with polymer side-chains, allows for the creation of interesting and unique morphologies. By combining structurally dissimilar backbone and grafts, core-shell bottlebrushes serve as candidates for materials with unique combinations of properties, such as mechanically rigid backbones combined with conductive grafts, a combination which could be useful as membranes in battery applications. In this talk, we present a field-theoretic model for the structure of bottlebrush copolymers and explore how architecture alters the traditional block copolymer phase diagram. We accomplish this via our recently developed theoretically informed Langevin dynamics (TILD) package for LAMMPS, in which the non-bonded forces are calculated using density fields in lieu of particle-based interactions. The TILD simulations capture the fluctuating version of the model, which is compared to the analytic RPA predictions for the ODT boundaries. Finally, we provide insight into the changes in the chain conformations and relate them to the shifts in the phase boundaries we observe.