Bouncing liquids

Never mind hydrophobic, how about "omniphobic"?

A new material—or rather, a new shape of an existing material—has been made that rejects nearly every liquid thrown at it, both oils and waters, both acids and bases. The material is a plastic, one with slightly lower surface energy than the famous PTFE (Teflon), so it has very little stick to it to begin with.

In order to make the liquids not only not stick but actually bounce right off, they changed the shape at a microscopic level so it wasn't a smooth flat surface, but a textured surface that was mostly air:

Posted with permission from J. Am. Chem. Soc., 2013, 135 (2), pp 578–581. Copyright 2012 American Chemical Society.

As you can see in the picture, the surface is a woven material, coated with this plastic, and that weave is what does the trick. Just watch those liquids bounce right off:

One of the things they're taking advantage of here, in addition to the low surface energy, is the intersection of liquid surface tension holding a drop together in air, and the woven textured surface having only small, spaced out bits touching the drop, with the gap between them small enough that the drop's own surface tension bridges the gap—keeping the drop in one piece, instead of spreading across a flat surface.

If they coat fabric instead of stainless steel mesh with this plastic, they could have lab coats that not only don't get wet, but that reject acids or bases that normally burn through cloth and skin, or tablecloths that never get wine or coffee stains.

The only liquids they mentioned testing that didn't bounce off were CFCs, which are used only in refrigerators and air conditioners and are kept in leak-proof containers because of their environmental hazards.

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