
Waterdrop animation courtesy of Anish Tuteja
A self-healing, water-repellent coating that’s ultra durable
It could enable waterproofing of vehicles, clothing, rooftops and countless other surfaces for which current waterproofing treatments are too fragile. It could also lower the resistance of ship hulls, a step that would reduce the fuel consumption of the massive vessels that transport 90 percent of the world’s cargo.
The developers say the new concoction is a breakthrough in a field where decades of research have failed to produce a durable coating. While water-repellent finishes are available at present, they’re typically not strong enough for applications like clothing or ship hulls. This discovery changes that.
“Thousands of superhydrophobic surfaces have been looked at over the past 20 or 30 years, but nobody has been able to figure out how to systematically design one that’s durable,” said Anish Tuteja, U-M associate professor of materials science and engineering. “I think that’s what we’ve really accomplished here, and it’s going to open the door for other researchers to create cheaper, perhaps even better superhydrophobic coatings.”
The coating is made of a mix of a material called “fluorinated polyurethane elastomer” and a specialized water-repellent molecule known as “F-POSS.” It can be easily sprayed onto virtually any surface and has a slightly rubbery texture that makes it more resilient than its predecessors.
If it is damaged, the coating can heal itself hundreds of times. It can bounce back “even after being abraded, scratched, burned, plasma-cleaned, flattened, sonicated and chemically attacked,” the researchers wrote in a paper recently published in ACS Applied Materials & Interfaces.
In addition to recovering physically, the coating can heal itself chemically. If water-repellent F-POSS molecules are scraped from the surface, new molecules will naturally migrate there to replace them. That’s how the coating can renew itself hundreds of times. Its healing ability is limited only by its thickness.
The discovery is being commercialized by HygraTek, a company founded by Tuteja with assistance from U-M Tech Transfer.
Beyond the coatings detailed in the paper, the project produced what amounts to a recipe that researchers can use to optimize future coatings to a specific application’s requirements for cost, durability and other factors.
As lead author and U-M doctoral student Kevin Golovin explains, the team used a process that was radically different from previous research in the field.
“Most materials science researchers have focused on identifying one specific chemical system that’s as durable and water-repellent as possible,” he said. “We approached the problem differently, by measuring and mapping out the basic chemical properties that make a water-repellent coating durable. And some of the results surprised us.”
For example, most hydrophobic coatings are made of two main ingredients: an active molecule that provides the water-repellency and a binder. Generally, researchers have assumed that using more durable ingredients would make a more durable coating. But Tuteja’s team found that that’s not necessarily the case.
They discovered that even more important than durability is a property called “partial miscibility,” or the ability of two substances to partially mix together. The other key variable the team discovered is the stability of the water-repellent surface.
Most water-repellent coatings work because their surface has a very specific geometry, often microscopic pillars. Water droplets perch on the tips of these pillars, creating air pockets underneath that deny the water a solid place to rest and cause it to roll off easily. But such surfaces tend to be fragile—slight abrasion or even the pressure of the water itself can damage them.
The team’s research found that a surface that’s slightly pliable can escape this pitfall—even though it seems less durable, its pliable properties enable it to bounce back from damage.
Tuteja estimates that the coatings will be available for use before the end of 2017 for applications including water-repellent fabrics and spray-on coatings that can be purchased directly by consumers.
Learn more: A self-healing, water-repellent coating that’s ultra durable
The Latest on: Superhydrophobic nanomaterials
via Google News
The Latest on: Superhydrophobic nanomaterials
- International event showcases the latest in materials innovationon February 17, 2021 at 4:00 pm
such as fire-resistant or superhydrophobic materials with anti-icing properties with applications in demanding sectors, such as construction and aeronautics.” Additives and nanomaterials offer many ...
- Recent Developments in Carbon Nanotube Spongeson February 12, 2021 at 6:09 am
Carbon nanotube sponges are randomly arranged, self-supporting, three-dimensional networks of interconnected carbon nanotubes. Carbon nanotubes are nano-sized structures bearing unique mechanical and ...
- Functional and versatile superhydrophobic coatings via stoichiometric silanizationon February 12, 2021 at 2:42 am
Superhydrophobic coatings have tremendous potential for applications in different fields and have been achieved commonly by increasing nanoscale roughness and lowering surface tension. Limited by ...
- Colloquium of the SPP 2171on February 11, 2021 at 4:00 pm
When and how self-cleaning of superhydrophobic surfaces works ... ranging from transport across biomembranes and plant movements to templating processes for nanomaterials and modern concepts of water ...
- Anti-icing performance on aluminum surfaces and proposed model for freezing time calculationon February 11, 2021 at 4:39 am
In this work, we proposed a facile approach to fabricate a superhydrophobic surface for anti-icing performance in terms of adhesive strength and freezing time. A hierarchical stru ...
- Global Anti-Microbial, Anti-Viral, and Anti-Fungal Nanocoatings Markets 2017-2030on February 4, 2021 at 11:41 am
The use of inorganic nanomaterials when compared with organic anti-microbial agents is also desirable due to their stability, robustness, and long shelf life. At high temperatures/pressures ...
- Worldwide Nanotechnology and Nanomaterials in Packaging Industry in 2021 - 78 Companies Profiled Including Asahi Kasei, Dow & Valentis Nanotechon January 22, 2021 at 12:52 pm
For more information about this report visit https://www.researchandmarkets.com/r/hv88te Research and Markets also offers Custom Research services providing focused ...
- Global Market for Nanotechnology and Nanomaterials in Packaging - Reduce Reliance on Petroleum-based Packaging - ResearchAndMarkets.comon January 20, 2021 at 9:42 am
DUBLIN--(BUSINESS WIRE)--The "The Global Market for Nanotechnology and Nanomaterials in Packaging" report has been added to ResearchAndMarkets.com's offering. Nanomaterials have already been ...
- Worldwide Sol-Gel Coatings Industry to 2030 - Nanomaterials Used in the Coatingson January 20, 2021 at 6:55 am
CONTACT: ResearchAndMarkets.com Laura Wood, Senior Press Manager [email protected] For E.S.T Office Hours Call 1-917-300-0470 For U.S./CAN Toll Free Call 1-800-526-8630 For GMT Office ...
via Bing News