Structure and Dynamics of Polymer/Star Polymer Composites
My first project in the Starr lab was motivated by exploring a novel polymer system, and resulted in a publication I shared with a few other Wesleyan students. Polymer composites are usually composed of a soft base and hard additives (e.g., gold or silver nanoparticles to a rubber vitrimer). Relatively less explored is the case when the additives are softer and more like the polymer themselves. Hence, we model a linear soft polymer matrix with a star polymer as the additive.
Structure and Dynamics of Composites of Star Polymers in a Linear Polymer Matrix. Cesar A. Castro Rubio, Jinpeng Fan, Max K. Hanrahan, Jack F. Douglas, and Francis W. Starr. Macromolecules 2023 56 (23), 9324-9335DOI: 10.1021/acs.macromol.3c01558
Phase Behavior and Surface Tension in a Dynamically-Linked Polymer Blend
One of the challenges of mixed-plastics recycling is sorting. Imperfectly-sorted recycled materials are often immiscible, and resist mixing due to high interfacial tension. Recent computational and experimental work has demonstrated dynamic crosslinks (short-lived inter-species bonds) as a viable agent for compatibilizing such blends. We implement a Metropolis-based MC algorithm for creating reversible dynamic bonds with the LAMMPS molecular dynamics simulator, which allows us to investigate the impact of dynamic crosslinking on phase behavior and surface tension.
Max K. Hanrahan, Evelyn Grandfield, Sanat K. Kumar, Jack F. Douglas, Francis W. Starr; Phase behavior, self-assembly, and interfacial tension of a dynamically linked polymer blend. J. Chem. Phys. 21 May 2026; 164 (19): 194907.
This work resulted in a publication in the Journal of Chemical Physics as a featured article, and received the honor of editor’s pick. This work was additionally showcased in an accompanying AIP Scilight article highlighting its significance.