Robust and Durable Water-Resistant Adhesive for Impact-Resistant Smart Windows

Smart hydrogels have attracted considerable attention as smart window materials. However, the existing gel-based smart windows are often unable to be applied to humid environments due to their extreme swelling in aquatic environments. Herein, a nucleobase-inspired water-resistant adhesive is successfully designed and cleverly applied in smart windows. The adhesive exhibits durable and robust adhesion in various aquatic environments, including water, seawater, physiological saline, NaCl solutions, and a wide range of pH solutions (pH = 1–10). The adhesive can maintain high adhesive strength (∼0.8 MPa) in different harsh water environments for up to six months. Remarkably, the adhesive can be directly brushed onto surfaces of various shapes and substrates for information encryption and smart windows. The smart windows not only display stable and recyclable transparency changes triggered by solvents but also impart ordinary brittle glass with excellent impact resistance for effective stress protection. The water-resistant adhesives exhibit promising applications in underwater sealing, underwater repairing, underwater electronic devices, and underwater soft robots. It is anticipated that the strategy of water-resistant adhesive coatings will offer a broad perspective for the advancement of next-generation smart windows.