What makes a surface attract or repel water that comes in contact with it is usually determined by the chemical coating on the surface. Teflon is an example of a chemical coating to which water adheres only slightly. Those waxes that are put on wood and metal surfaces that cause water to bead up and flow off rather than adhere to the surface are other examples of hydrophobic techniques.
But scientists at the University of Rochester have developed a technique of using etching patterns on a micro- or nanometer scale that can produce either super-hydrophobic or super-hydrophilic surfaces. The effects shown in the video are quite dramatic.
(Via Mark Frauenfelder.)
Interesting. I’m guessing that pipes made out of this material would have much less flow resistance, as well as high corrosion resistance.
My first thought is that such fine etching seems vulnerable to being abraded or coated with gunk, in the real world.
It seems very strange to think that any nanometer scale structure coulf be considered wear resisitant. Surely any detail that fine is going to be highly vulnerable if on an exposed surface, even with a durable material?
John Morales & Holms: I think a large part of the wear resistance is simply that water bounces off it, carrying dust particles with it. So it’s self-cleaning;
Interesting. I wonder if the average molecular size of the material that is being etched affects how/if it works?
I want my protective glasses and motorcycle helmet visor to have this!