Dynamically Switchable Polymer Architectures: Roles of Molecular Weight and Persistence Length for Improved Cyclization of Linear Polymers.

The ability to dynamically switch polymer architecture offers an opportunity to tailor materials with responsive, tunable properties for a wide range of applications from advanced drug delivery systems to adaptive structural materials that can adjust to varying environmental conditions. In this work, we aim to determine the polymer design characteristics that affect the dynamics of conformational changes between linear and cyclic topologies. We performed molecular dynamics simulations on isolated coarse-grained polymer chains of varying length and chain stiffness. We quantified the average ‘cyclization time’—i.e., the time necessary for the polymer chain ends to touch, which would be the first step in the cyclization process of a linear chain with reactive end groups. We found an optimal range of the ratio of polymer chain length to persistence length to facilitate rapid chain-end convergence, enabling the efficient formation of cyclic polymer structures. Our results provide quantitative insights into the role of molecular weight and persistence length in achieving dynamically switchable chain architectures. The polymer design criteria identified here open potential avenues for designing polymers with dynamic/switchable properties, potentially enabling the efficient transformation of linear polymers into cyclic analogues through controlled cyclization processes.