Structural color materials with reversible stimuli‐responsiveness to external environment have been widely used in sensors, encryption, display, and other fields. Compared with other stimuli, visible light is highly controllable both temporally and spatially with less damage to materials, which is more suitable for structural color patterning. Herein, a new diselenide‐containing shape memory material is prepared and used for creating patterns via visible light stimulus. In this system, the structural color originates from birefringence of stretched materials, whose shapes can be fixed while maintaining the mechanical stress. The fixed stress can be released by diselenide metathesis under visible light irradiation. By regulating the wavelength or irradiation time with a commercial projector, the pattern with tunable structural colors is realized and the structural color pattern can be erased and rewritten arbitrarily. During the patterning process, the optical signal is first stored as mechanical signal and then transformed back to optical signal. It is a new method for preparing visible‐light‐responsive structural color material and has great potential in display devices, anticounterfeiting labels, and data storage.

Mechanoresponsive luminescent (MRL) elastomers, which change their fluorescence color or intensity upon deformation, can facilitate simple strain detection through optical signals. Several polymers have been endowed with MRL properties by blending them with excimer-forming dyes, whose assembly and emission color are affected by deformation of the blended materials. However, access to elastic MRL polyurethanes based on this approach has proven difficult and usually requires the covalent incorporation of such dyes in high concentration. Here, we show that much simpler access to MRL elastomers is possible by blending thermoplastic polyurethane elastomers with a small weight fraction of a telechelic sensor macromolecule carrying two excimer-forming oligo(p-phenylene vinylene) dyes at the termini. While the mechanical properties of the two polyurethanes, which were selected because of their dissimilar mechanical behaviors, remain unchanged, the additive imparts these materials with MRL characteristics. Notably, the reliable and reversible detection of strains as low as 5% is possible. The highly sensitive mechanochromic response mirrors the deformation and relaxation processes occurring in these model polyurethanes and enabled a detailed analysis of the processes underlying the shape-memory properties in one of the polyurethanes, in which such behavior was imparted by a crystallizable soft segment.

A visible-light-responsive metathesis reaction between diselenide and ditelluride proceeding through a radical mechanism without catalysts.

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Quantification of metabolites present within exhaled breath is a major challenge for on-line breath analysis. It is also important for gauging the analytical performance, accuracy, reproducibility, reliability, and stability of...

Regulating the reactivity and equilibrium of a dynamic reaction is essential for adaptive chemistry and functional materials. Herein, cucurbituril‐based host‐guest interaction was embedded into the dynamic metathesis between diselenide and ditelluride to establish an equilibrium‐adaptive system. In this system, cucurbit[6]uril (CB[6]) selectively bound with diselenide while cucurbit[7]uril (CB[7]) bound with not only diselenide but also ditelluride and exchange product. The dynamic nature of diselenide bond was locked after forming the inclusion complex with CB[6]. Based on this selective locking effect, the Se−Te products were reversed back to diselenide and ditelluride reactants, which was an equilibrium regulating process. Therefore, by combining CB[6]‐based host‐guest interaction and dynamic diselenide chemistry, the reactivity of diselenide bond and the equilibrium of Se−Te metathesis was successfully regulated.

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