Contraction upon Bond Cleavage in Dynamic Polymer Networks

Demand for materials with unique properties has led to the development of polymer networks incorporating distinctive chemistries and crosslinking mechanisms. For example, polymer networks which contract in response to a stimulus have potential applications in areas such as artificial muscle, smart valves, drug delivery platforms, and other biomedical materials. In this work, we use coarse-grained molecular dynamics simulations to investigate the feasibility of incorporating polymer precursors into networks that counterintuitively contract upon the cleavage of dynamic bonds within the network. We perform simulations both of single junctions and of larger portions of the network to identify optimal designs for the polymer precursors and key design rules which lead to network contraction upon bond cleavage. The simulations show that polymer networks are capable of contraction when bonds within the network are cleaved, though the precursors must be precisely synthesized. These results provide quantitative guidance for experimental realization of network contraction induced by bond cleavage.