Now, a super water repellent that makes things unwettable

A researcher at the Department of Energys Oak Ridge National Laboratory (ORNL) has developed a water repellent that may revolutionise the commercial market.

Washington, Nov 30: A researcher at the Department of Energy's Oak Ridge National Laboratory (ORNL) has developed a water repellent that may revolutionise the commercial market.

The super-water repellent (super hydrophobic) material, developed by John Simpson, is a glass powder coating material with properties that can cause water-based solutions to bounce off virtually any coated surface.

The ORNL nano-structured material maintains a microscopic layer of air on surfaces even when submerged in water, resulting in a profound change in the basic water-solid interface. Simpson likes to refer to this as the "Moses effect."

Earlier, Simpson noted that superhydrophobic coatings lacked the durability and were expensive with poor quality.

"Existing high-quality superhydrophobic materials are generally relegated to university research laboratories because they are difficult and expensive to produce, not scalable to large volumes and not amenable to being made into a commercially viable coating," Simpson said.

The researcher found that powder's porosity and nanoscale-sharpened features amplify the effect of water's surface tension and causes the powder to become "unwettable."

Simpson also said that the repellent is easy to fabricate and uses inexpensive base materials.

"Such a superhydrophobic powder has many features and advantages, some of which include ease of manufacturing, low cost and scalability," he added.

Another feature of this powder is its thermal insulation characteristics. Water does not enter the grain pores because the powder grains are superhydrophobic.

This results in a dry breathable coating with trapped insulating air throughout.

And, because the powder consists almost entirely of porous amorphous silica, it also makes a very good electrical insulator.

The powder creates a layer of air between the coated substrate and any water on the surface, water-based corrosion of the substrate which greatly reduced or entirely eliminated.

The repellent will also create a new class of such products, including windshields, eyewear, clothing, building materials, road surfaces, ship hulls and self-cleaning coatings. The list of likely applications is virtually endless.

This research was funded by the Laboratory Directed Research and Development program.

ANI