Multidimensionally Programming Photoswitching via Orthogonal Covalent-Noncovalent Chemistry for Dual-Track...

Encoding targeted information into the temporal evolution of optical states, rather than relying on static on/off states, is essential for storage, optical encryption and anti-counterfeiting. However, achieving multiple independent information-display processes remains a challenge. Herein, a "dual-track" time-resolved optical encryption strategy is realized based on multidimensional programming of donor-acceptor Stenhouse adduct (DASA) photoswitching through orthogonal covalent-noncovalent chemistry. The temporal optical evolution during the photo-bleaching and thermal-recovery processes can be predictably programmed through the orthogonal combination of noncovalent interactions and covalent incorporation between DASAs and polyurethanes. Distinct from conventional strategies, noncovalent hydrogen-bonding interactions synchronously suppress the photo-bleaching rate (k_photo) and thermal-recovery rate (k_dark) through isomerization confinement, whereas covalent incorporation reshapes the isomerization energetics, simultaneously accelerating k_photo (2.4-fold) and retarding k_dark (60% decrease). This orthogonal regulation mode is generally applicable across diverse polyurethane chemistries and establishes a four-quadrant kinetic map for DASA photoswitching, providing multiple encoding units with distinguishable temporal optical evolution. The photo-bleaching and thermal-recovery processes function as two independent information-display tracks, allowing encrypted information to appear in either track, both tracks, or neither track. This work establishes a novel "dual-track" paradigm for optical encryption by decoupling information in reversible photoswitching processes.