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New "Hairy" Material Is Almost Perfectly Hydrophobic

drewsup writes "Wolfgang Sigmund, a professor of materials science and engineering at the University of Florida, has created a material modeled after spider hairs that acts as a nearly perfect water-repelling surface. Quoting Science Daily: 'A paper about the surface, which works equally well with hot or cold water, appears in this month's edition of the journal Langmuir. Spiders use their water-repelling hairs to stay dry or avoid drowning, with water spiders capturing air bubbles and toting them underwater to breathe. Potential applications for UF's ultra-water-repellent surfaces are many, Sigmund said. When water scampers off the surface, it picks up and carries dirt with it, in effect making the surface self-cleaning. As such, it is ideal for some food packaging, or windows, or solar cells that must stay clean to gather sunlight, he said. Boat designers might coat hulls with it, making boats faster and more efficient.' Hairy glass, anyone?"

3 of 133 comments (clear)

  1. Do boats go faster because it repels water? by wisebabo · · Score: 4, Interesting

    Would there be a (very) thin layer of air between the boat and the water? Would there be a reduction in friction akin to the thin layer of water created when a skater's skates press down on the ice?

    Or would boats go faster because no barnacles or mussels could become fastened on the hull of a boat? (I've heard that this used to be combatted with very toxic copper based compounds, no idea what they use now). If these microscopic hairs that were lifted from spiders work really well in preventing "fouling", why haven't whales evolved the same?

    Just askin'.

    1. Re:Do boats go faster because it repels water? by osu-neko · · Score: 3, Interesting

      Indeed. It's worth nothing that, relatively speaking, whales are a fairly new evolutionary development. The first whales appear on the scene a mere 50 million years ago. The other question is one of competition. Some astoundingly suboptimal, inefficient designs have survived in nature for millions of years when they lacked significant competition or pressure in their niche. Whales don't seem to face a lot of competition or pressure, even less since we thinned their numbers in recent centuries.

      Long story short, whales are unlikely to be anywhere near an optimal solution for their niche, and are unlikely to become one anytime soon.

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  2. Battery/Fuel Cell Air Cathode? by Black+Gold+Alchemist · · Score: 3, Interesting

    It seems like this would be good as a battery/fuel cell air cathode. You could put this stuff, then a layer of activated charcoal, then a current collector. This would cause the water-air interface to be somewhere inside the activated charcoal, so you would end up with a huge surface area of the air/water interface. This would improve alkaline fuel cells of all types (aluminium, iron, zinc and hydrogen).

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