关键词: 聚集诱导发光（AIE）, 水凝胶, 多刺激响应, 机械性能, 氢键网络

Abstract: This study presents a multi-stimuli-responsive hydrogel, P(VI-co-MAAC-NE), which was successfully constructed by covalently integrating the aggregation-induced emission (AIE) moiety (Z)-N-(4-(1-cyano-2-(4-(diethylamino)phenyl)vinyl)-phenyl)methacrylamide (NE) into a dynamic hydrogen-bonding network composed of 1-vinylimidazole (VI) and methacrylic acid (MAAC) groups. The dense hydrogen-bonding network not only provides enhanced mechanical robustness but also significantly enhances the AIE effect of NE by restricting its molecular motion. Under various external stimuli, the hydrogen bonds within the hydrogel network undergo reversible dissociation and reformation, thus enabling synergistic modulation of the hydrogel’s mechanical properties and luminescence behavior. Specifically, organic solvents disrupt the hydrogen-bonding network and the aggregation of the AIE moiety NE, resulting in macroscopic swelling and fluorescence quenching of the hydrogel; in strongly acidic conditions, protonation of NE molecules suppresses the intramolecular charge transfer (ICT) process, yielding a blue-shifted emission band accompanied by intense blue fluorescence; in highly alkaline environments, deprotonation of carboxyl groups induces hydrogel swelling and disperses NE aggregates, leading to pronounced fluorescence quenching. Moreover, the system exhibits thermally activated shape-memory behavior: heating above the glass transition temperature (Tg ≈?62?°C) softens the hydrogel to allow programmable reshaping, and subsequent hydrogen bond reformation at ambient conditions locks in the resultant geometries without sacrificing the hydrogel’s fluorescence performance. By capitalizing on these multi-stimuli-responsive characteristics and shape-memory behavior, the potential of hydrogel P(VI-co-MAAC-NE) for advanced information encryption and anti-counterfeiting applications is demonstrated. This work not only provides a versatile material platform for sensing and information storage but also offers new insights into the design of intelligent soft materials integrating AIE features with dynamically regulated supramolecular network structures.

Key words: Aggregation-induced emission(AIE), Hydrogels; Multi-Responsive, Mechanical properties, Hydrogen bonds network