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Abstract Bicontinuous cubic (Q) lyotropic liquid crystal (LLC)‐derived polymer networks possess periodic, uniform‐size, 3D‐interconnected nanopores that make them highly desirable organic materials for selective molecular separation and uptake applications. To date, there are no reported examples of a Q‐phase network with additional functional properties, such as catalytic reactivity, response to external stimuli, or gated transport, that would expand the usefulness of this class of porous materials. Here, a functionalized gyroid‐type Q polymer network material that can be used for potential gated transport or adaptive uptake applications is presented. This material contains a novel spiropyran‐containing dopant monomer that upon blending and cross‐linking with a gyroid‐forming LLC monomer, yields a gyroid polymer material that retains its phase architecture while reversibly responding to changes in external solution and vapor pH. Studies also demonstrate that this system is capable of strongly binding to aq. Pb²⁺ions when activated by UV light, allowing it to function as a potential colorimetric sorbent or gated‐response material. 

Abstract The preparation of thin films of nanostructured functional materials is a critical step in a diverse array of applications ranging from photonics to separation science. New thin‐film fabrication methods are sought to harness the emerging potential of self‐assembled nanostructured materials as next‐generation membranes. Here, the authors show that nanometer‐scale control over the thickness of self‐assembled mesophases can be enacted by directional photopolymerization in the presence of highly photo‐attenuating molecular species. Metrology reveals average film growth rates below ten nanometers per second, indicating that high‐resolution fabrication is possible with this approach. The trends in experimental data are reproduced well in numerical simulations of mean‐field frontal photopolymerization modeled in a highly photo‐attenuating and photo‐bleaching medium. These simulation results connect the experimentally observed nanometer‐scale control of film growth to the strong photo‐attenuating nature of the mesophase, which originates from its high‐aromatic‐ring content. Water permeability measurements conducted on the fabricated thin films show the expected linear scaling of permeability with film thickness. Film permeabilities compare favorably with current state‐of‐the‐art nanofiltration and reverse osmosis membranes, suggesting that the current approach may be utilized to prepare new nanoporous membranes for such applications.