United States. The new self-healing, water-repellent and spray coating that has been developed at the University of Michigan ensures that it is hundreds of times more durable than its counterparts.
The new coating could allow for the waterproofing of vehicles, clothing, roofs and countless other surfaces for which current waterproofing treatments are too fragile. It could also reduce the strength of ships' hulls, a step that would reduce the fuel consumption of massive ships carrying 90 percent of the world's cargo.
The coating is made of a mixture of a material called "fluorinated polyurethane elastomer" and a specialized water-repellent molecule known as "F-POSS." It can be easily sprayed on virtually any surface and has a slightly elastic texture that makes it more resistant than its predecessors.
If it is damaged, the lining can heal hundreds of times. It can bounce "even after it has been worn, scratched, burned, plasma cleaned, flattened, sonicated and chemically attacked," the researchers wrote in a paper recently published in ACS Applied Materials & Interfaces.
The developers say the new blend is a breakthrough in a field where decades of research have failed to produce a durable coating. Although water-repellent finishes are available today, they are usually not strong enough for applications such as clothing or ship hulls. This discovery changes that, the researchers explain.
The coating can be chemically cured. If the water-repellent F-POSS molecules are scraped off the surface, new molecules will naturally migrate there to replace them. This is how the coating can be renewed hundreds of times. Its healing capacity is limited only by its thickness.
"Thousands of superhydrophobic surfaces have been examined in the last 20 or 30 years, but no one has been able to systematically design one that is durable," said Anish Tuteja, U-M associate professor of materials science and engineering. "I think that's what we've really achieved here, and it's going to open the door for other researchers to create cheaper, maybe better, superhydrophobic coatings."
Source: University of Michigan.
