Reaction-driven solvent transport in UV-curable phase-separating coatings

Abstract We experimentally examined the time-evolutions of local compositions in photocurable, monomer-solvent-initiator ternary liquid film coatings using attenuated total-reflectance-Fourier transform infrared spectroscopy. The exhibited phase separation upon UV exposure owing to inherent partial miscibility between solvent and polymer. concentration at bottom coating increased when exposed light for 1 s from top, showing a transport along irradiation direction. differences before after showed good agreement with model predictions based on stress-induced non-Fickian mass transport. concentrations remained constant case discrete structures, whereas it exponentially decayed over time bicontinuous structures. These results suggest that light-tunable microstructures enable relaxation reaction-driven nonuniformity distributions.