MIT Has Created The Most Slippery Surface By A Factor Of 10,000 [View all]

[n2doc]

MIT scientists have created a new kind of hydrophobic material that is incredibly slippery, beating existing hydrophobic surfaces by a factor of 10,000.

The key to the improved hydrophobic (water-shedding) surface is a combination of microscopic patterning—a surface covered with tiny bumps or posts just 10 um across, about the size of a red blood cell—and a coating of a lubricant, such as oil. The tiny spaces between the posts hold the oil in place through capillary action, the researchers found.
The team discovered that droplets of water condensing on this surface moved 10,000 times faster than on surfaces with just the hydrophobic patterning. The speed of this droplet motion is key to allowing the droplets to fall from the surface so that new ones can form, increasing the efficiency of heat transfer in a power plant condenser, or the rate of water production in a desalination plant.

With this new treatment, "drops can glide on the surface," Varanasi says, floating like pucks on an air-hockey table and looking like hovering UFOs—a behavior Varanasi says he has never seen in more than a decade of work on hydrophobic surfaces. "These are just crazy velocities."

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http://www.technovelgy.com/ct/Science-Fiction-News.asp?NewsNum=3795
http://www.rdmag.com/news/2012/10/better-way-shed-water