Researchers discover new method to make tougher adhesives

Team of researchers from Purdue University have developed an advanced adhesive technology, in order to make adhesives for construction, vehicles and electronics tougher than usual.

According to Jonathan Wilker, a Purdue professor of chemistry and materials engineering, the team drew inspiration from sea creatures to develop several new adhesives. Wilker added that one way to make the adhesive materials tougher is by making them weaker.

During the study, the team added bonds which could be broken easily throughout the material. The team alleges when stress or pressure is applied to the glue, the sacrificial bonds absorb energy and break apart. On the other hand, the rest of the larger adhesive system remains intact.

Wikler’s team experimented the idea on several types of bonds. Findings revealed the ones that worked best were neither too weak nor too strong. Wilker further also confirmed that the technique for managing energy in adhesives was a general phenomenon which could be applied to adhesives in industries ranging from consumer electronics, construction, manufacturing airplanes and automobiles.

For the research the team has worked on hundreds of mussels and oysters, grown in the laboratory for studying proteins used by sea creatures sticking to rocks. After understanding the nature of these natural adhesives, researchers created several synthetic versions by using different properties.

“The idea is somewhat similar to how a brick wall is made of bricks that are offset from each other,” explained Wilker. “You stagger the bricks and cement so that a crack does not shoot right down through the cement lines. A crack hits the middle of a brick and the forces get spread out toward both sides, eventually decreasing to the point that the wall stays intact.

“We added weak bonds within the adhesive so that mechanical forces and growing cracks lose energy by breaking these bonds instead of having the whole, larger material fracture. The idea is to manage how energy moves through the material. The overall adhesive system can become tougher and less likely to break apart when placed under mechanical stress.”