Researchers from Purdue University have just synthesized an underwater adhesive that’s modeled after mussels; and it’s stronger than any popular commercial brand underwater adhesive.
“Our current adhesives are terrible at wet bonding, yet marine biology solved this problem eons ago,” said Jonathan Wilker, Chemistry and Materials Engineering professor at Purdue University. “Mussels, barnacles, and oysters attach to rocks with apparent ease. In order to develop new materials able to bind within harsh environments, we made a biomimetic polymer that is modeled after the adhesive proteins of mussels.” He adds.
Source: Purdue University
The researchers synthesized the strong bio-based underwater glue by studying how these mussels extend their hair-like fibers that attach to any hard surface by coating them with layers of adhesives. The glue found in these mollusks contain a protein made out of the amino acid “DOPA”, which provides the strength needed for strong adhesion in underwater environments. They then used the chemistry in these proteins as a basis to synthesize a biomimetic polymer called poly(catechol-styrene), which was created by harnessing the chemical structure of compounds called catechols, which are found in DOPA.
Source: Indian Express
They then conducted a series of tests to see how this polymer performs in tanks of artificial seawater, and the results were outstanding. They found that the biomimetic glue performed better than 10 commercially available underwater adhesives when it was used to bond with polished aluminum. It also was the only glue in the study capable of bonding wood, and out-performed the strongest adhesives when bonded with Teflon.
Source: Youtube, Purdue Engineering
“These findings are helping to reveal which aspects of mussel adhesion are most important when managing attachment within their wet and salty environment,” Wilker explained. “All that is needed for high strength bonding underwater appears to be a catechol-containing polymer.”
The material was also surprisingly stronger than the natural adhesives found in mussels. 17 times stronger, in fact. These baffled the scientists, as “In biomimetics, where you try to make synthetic versions of natural materials and compounds, you almost never can achieve performance as good as the natural system,” said Wilker.
The reason for this might be because that these aquatic animals have evolved to create adhesives that were only as strong as they needed them to be in their environments. These glues might’ve been designed in such a way that it can still easily break off from the connected surface when the animals are being hunted by predators, without damaging their internal organs.
In the future, the researchers want to enhance this material for more practical uses in a real world, open water environment.
The research was written and conducted by doctoral graduates Michael A. North and Chelsey A. Del Grosso, and Jonathan Wilker.