A nanoscale coating repels the broadest range of liquids of any material in its class, causing them to bounce off the treated surface, according to the University of Michigan engineering researchers who developed it. In addition to stain-resistant clothes, the coating could lead to breathable garments to protect soldiers and scientists from chemicals, and advanced waterproof paints that dramatically reduce drag on ships.
To apply the coating, the researchers employ a technique called electrospinning that uses an electric charge to create fine particles of solid from a liquid solution. So far, they've coated small tiles of screen and postage-stamp-sized swaths of fabric.
The coating is a mixture of rubbery plastic particles of "polydimethylsiloxane," or PDMS, and liquid-resisting nanoscale cubes developed by the Air Force that contain carbon, fluorine, silicon, and oxygen.
Watch the video below.
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Transcript
00:00:04 we've developed these so-called super omniphobic surfaces and essentially all these liquids Just Bounce right off the surface we believe our surfaces can now repel the broadest range of liquids that that have ever been tested even in cases where people have been able to repel them essentially liquids just remain stuck on the surface they don't roll off and so it was a big
00:00:26 achievement for us to be able to cause all these liquids to roll off the surface and actually bounce on these surfaces the liquid actually starts to sit on millions of pockets of air um and I would imagine on the order of 95 to 99% of the liquid is actually just touching air it's only one touching 1 to 5% of the surface and that has to do with the right surface texturing that we
00:00:49 impart on the coating one of the most direct applications perhaps is in the area of coating fabrics for army uniforms that prevent them from chemical and biological attack things like fingerprint resistant surfaces so if you think of your iPhone or iPod screen and you see a lot of your fingerprints appearing drag reduction for ships uh so as ships move uh across the sea um then
00:01:12 they experience much less drag because of the application of these Coatings the whole goal for all of these things is is to be uh sort of all encompassing where they're trying to actually repel all sorts of liquids that you might come in contact with because many in many situations you don't really know what kind of a liquid that you might be dealing with and so this would
00:01:33 essentially offer a general protection against a wide range of chemicals and and liquids I've been working in this area for about 5 years now and the first 2 years I wouldn't have believed that we could actually make Coatings like this where you can repel all these range of liquid especially very very low surface tension liquids like we've been able to
00:01:51 do so now essentially nothing sticks on these Coatings um even if you tilt our Coatings by one or two degrees everything just rolls or slides right off and that's a very amazing uh achievement
