Getting glued in the sea

Inspired by ocean organisms, scientists have been developing adhesives for application in the marine environment. However, water and high salinity, which not only weaken the interfacial bonding by the hydration layer but also induce the deterioration of adhesives by erosion, swelling, hydrolysis, or plasticization, are detrimental to adhesion, resulting in specific challenges in the development of under-seawater adhesives. In this focus review, current adhesives that are capable of macroscopic adhesion in seawater were summarized. The design strategies and performance of these adhesives were reviewed based on their bonding methods. Finally, some future research directions and perspectives for under-seawater adhesives were discussed.