Solvent induced amplification of the photoresponsive properties of α,ω-di-[4-cyanophenyl-4′-(6-hexyloxy)-azobenzene]-poly(N-isopropylacrylamide) in aqueous media

Abstract

Irradiation at room temperature of α,ω-di-[4-cyanophenyl-4'-(6-hexyloxy)-azobenzene]-poly-(N-isopropylacrylamide) (Az(2)-PNIPAM) solutions in water/1,4-dioxane (6 mol% dioxane) reversibly converts a turbid suspension into a clear solution, demonstrating for the first time that cononsolvency of PNIPAM in mixed aqueous solvents in synergy with preferential chromophore solvation can act as actuators of responsive systems.