10-Second Superglue Could Transform Underwater Repairs

Engineers have developed a new high-performance adhesive that can bond surfaces underwater in as little as 10 seconds, withstand continuous immersion for more than three years and retain its bonding ability after repeated detachment and reattachment. The breakthrough, described in a study published in Nature Communications, could offer a new way to repair and maintain structures exposed to water, including marine infrastructure, pipelines and other submerged equipment. According to a report by ScienceAlert’s Ivan Farkas, the adhesive addresses one of the biggest challenges facing conventional underwater bonding: the thin layer of water that forms between an adhesive and the surface it is intended to join.

That water layer can prevent adhesives from making proper contact with surfaces while also weakening or washing away bonding materials over time. The researchers developed the material from a supramolecular ionic liquid known as BP16TPB, combining flexible and rigid molecular components to create a structure capable of reorganizing itself when exposed to water. The material is mixed with dimethyl sulfoxide (DMSO), a solvent that helps dissolve the BP16TPB and separates some of its molecules into mobile, electrically charged particles. When the resulting adhesive comes into contact with water, those particles reorganize and assemble into a stable structure.

According to the researchers, the process involves the formation of hydrogen bonds and π-π stacking interactions, producing a dense and water-resistant network that transforms the initially flow-able material into a strong adhesive layer. The process is also assisted by the Marangoni effect, a phenomenon in which differences in surface tension cause fluids to move. This helps the adhesive spread across and coat surfaces before the molecular restructuring locks the material into place. One of the most significant findings was the speed and strength of the adhesive’s underwater performance.

Tests showed that after only 10 seconds of curing underwater, the material achieved an adhesive strength of approximately 1.1 million pascals. The researchers tested the adhesive on several materials, including ceramic, epoxy and plastics, demonstrating its ability to form strong bonds across different types of surfaces. Its performance was not limited to a particular water environment. The adhesive retained its bonding capability in acidic, alkaline and salty electrolyte solutions, suggesting potential applications in a range of challenging underwater conditions. Beyond its rapid bonding, the material demonstrated notable long-term durability. In one extended test, the adhesive supported a 2-kilogram (4.4-pound) weight continuously for more than three years while submerged.

The researchers said the long-term test provided evidence that the material could resist both degradation caused by water at the bonding interface and gradual structural deformation, known as creep, over multi-year periods. The adhesive also showed a degree of reusability. After being detached and reattached underwater, it maintained reliable adhesive performance through eight bonding cycles, indicating that it could potentially be useful in applications where components need to be temporarily secured, removed or repositioned.

The development could have implications for the maintenance of structures that are difficult or expensive to remove from water for repairs. Underwater pipelines, marine equipment, vessels, offshore structures and other submerged infrastructure often require specialized maintenance because conventional adhesives can struggle in wet environments. A material that can rapidly establish a strong bond without requiring surfaces to be completely dried could simplify some of those operations. The researchers said the combination of strong water-repelling properties and reversible, non-covalent molecular interactions enables the adhesive to overcome the water barrier that normally interferes with underwater adhesion.

Despite its promising performance, the material has limitations. The adhesive becomes sensitive when temperatures rise above 70 degrees Celsius (158 degrees Fahrenheit), potentially restricting its use in high-temperature environments. The researchers nevertheless described the work as more than simply the development of a stronger underwater glue. They said the findings demonstrate a broader strategy for creating environmentally responsive smart materials whose properties can change in response to their surroundings.

The study, published in Nature Communications, could therefore mark an important step towards adhesives designed specifically for demanding environments where conventional bonding technologies have struggled.

By: Joyce Owusu