New "Hairy" Material Is Almost Perfectly Hydrophobic 133
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?"
Raw Data Video (Score:5, Informative)
Available here free of charge:
http://pubs.acs.org/doi/suppl/10.1021/la903813g [acs.org]
Re:Raw Data Video (Score:4, Informative)
Warning.. movies appear to be in crap-tastic Indeo 5 format
The Problem (Score:5, Informative)
Re:Do boats go faster because it repels water? (Score:2, Informative)
actually sharks have unidirectional scales and dolphins are hairy, neither are affected by barnacles like whales
Nottingham Univ. super hydrophobic demo (Score:5, Informative)
Here's the video [youtube.com]. Fascinating stuff-- the first sample is a copper plate with copper oxide crystals coated in a material very similar to Teflon.
Re:Do boats go faster because it repels water? (Score:5, Informative)
Another well known hairy material... (Score:5, Informative)
Another well known hairy material is asbestos. Just sayin'
old news and the hype is only partly true. (Score:3, Informative)
Superhydrophobicity by thin trapped air layers is not new at all - I recall seeing a seminar in my physics department ~10 years ago. The self-cleaning aspect does work nicely, but generally the surface structures lack the durability to last long enough to be useful. It also doesn't work for boat hulls because the air slowly dissolves into the water until the trapped air layer is lost.
Re:Do boats go faster because it repels water? (Score:4, Informative)
(I've heard that this used to be combatted with very toxic copper based compounds, no idea what they use now).
When I worked for some ship systems company, they used the desalination slurry (byproduct of the freshwater-making systems). Basically, they made the water around the ship too salty for things to want to stick around... Literally.
Re:We'll know how effective it is (Score:2, Informative)
Re:Do boats go faster because it repels water? (Score:3, Informative)
If these microscopic hairs that were lifted from spiders work really well in preventing "fouling", why haven't whales evolved the same?
Sharks have evolved a mechanism which already works extremely well and is now actively being used for ocean faring ships [sharkskincoating.com]. Just because sharks have evolved such a mechanism, why would you assume whales would? Besides, sharks are predatory creatures, where the extra performance is likely key to their continued success, whereas most whales which suffer from fowling are typically not predatory.
Re:I Feel Better Already (Score:3, Informative)
My wife really wanted a pet tarantula, but her Doctor advised against it due to the fact that she's a severe asthmatic.
Those little spiky hairs get everywhere apparently.