Tough and On‐Demand Detachable Wet Tissue Adhesive Hydrogel Made from Catechol Derivatives with a Long Aliphatic Side Chain

, and its adhesion strength to wet porcine skin is ≈153 kPa. These values are much higher than those of dopamine-based adhesives in the same conditions, demonstrating that the long aliphatic side chain on catechol can greatly improve the wet tissue-adhesion. Additionally, the tough interfacial adhesion can be broken on demand with 5 wt.% aqueous urea solution. This adhesive hydrogel is highly promising in safe wound closure.