Fig. 1
From: Light-switchable LCST windows in an ionic liquid solution of azobenzene copolymers

Conceptual illustration of light-programmable solubility switching of P(AzoMA-r-PhEtMA) in the ionic liquid [C2mim][TFSI] at 37 °C. Visible-light irradiation (436 nm) enriches the trans-state, rendering the polymer insoluble and inducing phase separation, whereas UV irradiation (365 nm) enriches the cis-state, restoring solubility and yielding a homogeneous solution. The photographs show representative solution states under the two irradiation conditions