Sensitized Disequilibration of Water-Soluble Azopolymers

Abstract

Photo-responsive systems based on azobenzenes usually require UV light for E→Z isomerization, limiting their applicability, especially in biomedical contexts. Disequilibration by sensitization of azobenzene under confinement (DESC) has recently emerged as a supramolecular strategy to bypass this limitation without the need to derivatize the azobenzene scaffold. Here, we expand DESC to water-soluble azopolymers obtained by RAFT polymerization and systematically investigate the interplay between the polymer structure and DESC efficiency. Using this approach, we achieved as much as 85% of the direct photoexcitation (UV) switching efficiency, while utilizing low-energy (yellow) light. These results establish general design principles for combining DESC with polymeric systems, opening new opportunities for the development of functional materials driven with low-energy light.