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"Superomniphobic" Nanoscale Coating Repels Almost Any Liquid

cylonlover writes "A team of engineering researchers at the University of Michigan has developed a nanoscale coating that causes almost all liquids to bounce off surfaces treated with it. Creating a surface structure that is least 95 percent air, the new 'superomniphobic' coating is claimed to repel the broadest range of liquids of any material in its class, opening up the possibility of super stain-resistant clothing, drag-reducing waterproof paints for ship hulls, breathable garments that provide protection from harmful chemicals, and touchscreens resistant to fingerprint smudges."

25 of 104 comments (clear)

  1. Old News ... by SpockLogic · · Score: 4, Funny

    Obi-Wan Kenobi foretold this in 1951 http://www.imdb.com/title/tt0044876/

  2. I repel most liquids too by FeatherBoa · · Score: 4, Funny

    I repel most liquids too, although beer and coffee keep slipping though my formidable defences.

    1. Re:I repel most liquids too by VortexCortex · · Score: 2

      The hardware should be fluid resistant, but your resistance is futile. Don't tell me you haven't learned the Osmosis trick. It saves a lot of drinking time just bathing in it, and since you're not going to put it in your mouth you can even eliminate most trips to the toilet.

      Ahhh, Beeffee.

  3. What uses come to mind? by Commontwist · · Score: 4, Interesting

    I know that lawn mowers, should you leave gas in them for a while, will gain a 'coating' that gums up the fuel needle in the carburetor. Cleaning out the carb is a true pain and costs a lot to get a mechanic to clean/replace. Would this kind of coating over that small and delicate part help ease/eliminate sticking?

    1. Re:What uses come to mind? by oodaloop · · Score: 3, Insightful

      Motorcycle visors come to mind. And, you know, all those other ones mentioned in TFS. And white suits.

      --
      Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
    2. Re:What uses come to mind? by Em+Adespoton · · Score: 2

      Any place we currently use a lubricant would find this useful, as coating the parts in this prior to lubrication *should* decrease wear through a decrease in friction. Theoretically, this surface should also wear extremely well provided it's always coated in a lubricant.

      Two layers of this with an oil layer in between would be a performance and durability boost for most things that have moving parts.

      Now we just need to decrease production cost/increase production and discover how it stands up to *other* forces (such as radiation [heat, light, etc], corrosion, and motion) and what effects it has on its environment (carcinogenic etc).

    3. Re: What uses come to mind? by skitchen8 · · Score: 2

      Or, and IANAL (I am not a lawnmower-mechanic), you could stop leaving your lawnmower with gas in it for extended periods. Step one: disconnect gas line and drain gas into external vessel. Step two: start lawnmower and let run until it stops on its own accord. Or, even easier if less environmentally friendly, at the end of the lawnmowing season let lawnmower run until it stops of its own accord. No science required.

    4. Re:What uses come to mind? by fluffy99 · · Score: 2

      Repelling fluids does not imply low friction or even durability, for example water beading up on soft silicon rubber. Plus I would think you would want an oil attracting surface for a friction surface.

    5. Re:What uses come to mind? by tlhIngan · · Score: 2

      I know that lawn mowers, should you leave gas in them for a while, will gain a 'coating' that gums up the fuel needle in the carburetor. Cleaning out the carb is a true pain and costs a lot to get a mechanic to clean/replace. Would this kind of coating over that small and delicate part help ease/eliminate sticking?

      Gasoline is volatile. It will evaporate quite rapidly at room temperature.

      However, the gas you get from the pump has a bunch of additives and other stuff added to it - detergents to keep your engine clean (mandated by law, actually), as well as heavier hydrocarbons that aren't as volatile and such. So what happens is when you leave your lawnmower over the season is the light stuff evaporates out, leaving the heavy gunk behind - detergents, additives, and more importantly, varnish and the like which gum up the tiny passages in your carb.

      Basicaly before putting it away, at the very least put it away without any gas in the tank - run it all the way empty which should clear the tank and most of the carb. You can optionally choose to drain the leftover out of the carb, too.

  4. Yet another miracle nano-coating by Spy+Handler · · Score: 4, Insightful

    Every x months for the past 5 years I hear about some new super-coating that repels dirt, water, oil etc.. Every time I'm like, "cool, when will it come standard on new cars?" I hate having to wash my car every few days (it's parked outside) or it starts looking like crap.

    I suppose when I get a flying car, that's when I'll finally see this miracle coating in action.

    1. Re:Yet another miracle nano-coating by norpy · · Score: 4, Insightful

      Hopefully this clears things up for you:

      http://xkcd.com/678/

    2. Re:Yet another miracle nano-coating by Anonymous Coward · · Score: 5, Informative

      Every x months for the past 5 years I hear about some new super-coating that repels dirt, water, oil etc.. Every time I'm like, "cool, when will it come standard on new cars?" I hate having to wash my car every few days (it's parked outside) or it starts looking like crap.

      I suppose when I get a flying car, that's when I'll finally see this miracle coating in action.

      Posting anonymously because of a personal connection to research some of these materials, but I think it's worth it to quickly clear up a few uncertainties I see in the comments already posted:

      1) The reason you don't see this stuff all over is that these materials are expensive and usually not durable. Nanoscale patterns can be created through a variety of approaches, some of which are a bit more complicated but can repair or recreate their surface patterns after abrasion. As you might expect, the materials that can recreate their surface patterns tend to be on the more expensive end of the scale.

      2) The past 5 years have seen major progress in *phobic materials. We're getting closer to cost effective, more durability, and even better phobicity, but we're still not there.

      3) Superhydrophobic isn't the same as omniphobic. Generally surfaces will either have a high contact angle with water OR with nonpolar liquids. Superhydrophobic means the contact between a droplet of water and the material will be extremely small. Omniphobic means the surface repels both polar and nonpolar liquids.

      4) Nanoscale patterning of a surface can also lead to superhydrophilicity, the opposite of superhydrophobicity. The mechanism for this isn't fully understood.

  5. Democrats? by dhalsim2 · · Score: 4, Funny

    I know a few Democrats that were superromneyphobic.

    1. Re:Democrats? by jeffb+(2.718) · · Score: 2

      Expialidocious.

  6. How that compare to the non-stick bottle from MIT? by Taco+Cowboy · · Score: 4, Interesting

    This "Superomniphobic" Nanoscale Coating Repels Almost Any Liquid, but on the other hand, MIT's also nanoscale Liquiglide non-stick coating allows even sticky stuffs such as ketchup to flow out of the bottle completely.

    http://www.designboom.com/design/liquidglide-ketchup-bottle-by-mit-researchers/

    I must admit that I'm not familiar with both of these technological development, so... Can someone familiar with them explain to us the similarity / compatibility of both developments?

    Thanks !

    --
    Muchas Gracias, Señor Edward Snowden !
  7. Re:How do I wash my shirt? by Em+Adespoton · · Score: 3

    So a shirt that you essentially can't wash? You get charcoal or some other dust and you're out of luck!

    Charcoal acts as a fluid (yay carbon!) so that shouldn't be an issue. If you only coat the outside, you should still be able to clean the fabric from the inside.

    Or, just dry-clean ;)

  8. Re:How bout a waterless slip-and-slide? by The+Archon+V2.0 · · Score: 2

    Solution: Liquid concrete!

  9. Re:Comparison to Neverwet by peragrin · · Score: 2

    I don't know about wipers but rain x washer fluid is noticeable.

    during heavy rain you can watch the bead and run off your windshield.

    --
    i thought once I was found, but it was only a dream.
  10. Re:Comparison to Neverwet by slew · · Score: 4, Informative

    All this superhydrophobic stuff is mostly just silicone.

    The main difference is how it's applied and what type of structure it forms. As I understand it RainX is mostly just a simple silicone coating where the idea is to just smooth out the windshield (in the theory that on a completely smooth surface, water is more likely to bead than whet). NeverWet is a silicone nano-particles suspended in a spray/solvent. When the solvent evaporates, it makes a somewhat uniform coating of nano-particles of silicone.

    Apparently in this technique, they apply silicone with electrospinning instead of run-of-the-mill spray-n-dry techniques. The main difference is that with electrospinning it is accomplished w/o w/o solvents and the result can be made into a very uniform nano-structure. There's also no solvent to ruin whatever you need to apply it to. Of course figuring out the right technique to create a specific nano-structure that works as you intend it isn't an accomplishment to be sneezed at (not that it would stick anyhow)...

  11. Re:Exterior coating for condoms? by JazzXP · · Score: 2

    You know this is /. right? ;-)

  12. Almost useless in practice, however. by mark-t · · Score: 2

    It's my understanding that this kind of surface erodes relatively quickly, and thus rapidly loses its liquid repelling properties as it is handled or touched by other things that are solid in far too brief a time to be practical for anything but a temporary coating.

    1. Re:Almost useless in practice, however. by Subjective · · Score: 2

      If the object is not often moving and rubbing against other objects (mmmm... rubbing), then the coating need not be temporary.
      Dust-proof museum art.
      Spider-proof ceilings (seriously, this is all I can think of). I guess it's not very useful that way.

      The insides of windows?

      Basically any object which is furniture.

      --
      My other .sig is also this bad
  13. Re:Comparison to Neverwet by reverseengineer · · Score: 3, Informative

    This coating is actually not just silicone, but a blend of silicone and " liquid-resisting nanoscale cubes developed by the Air Force that contain carbon, fluorine, silicon and oxygen," which is apparently supposed to be layman's terms for fluorodecyl polyhedral oligomeric silsequioxane (POSS). Those are cubic networks of silica that have a fluorocarbon chain at each vertex, sort of a three-dimensional Teflon. The very low chemical reactivity plus the nanoscale roughness of the surface causes the lotus effect. The mixture with silicone helps the POSS adhere to materials, though they state in their paper that the POSS preferentially segregates to the surface and is responsible for the coating's properties:

    "A wide range of organic chemicals including toluene and chloroform, which readily wet/swell cross-linked PDMS, are also easily repelled. Even when our surfaces are immersed in a liquid bath of PDMS (Mn = 800 Da, lv = 19.8 mN/m), a plastron (air pockets) layer that is indicative of a robust Cassie–Baxter state is formed. The plastron layer was stable and remained unchanged even upon extended exposure to un-cross-linked PDMS. Note that PDMS is a major constituent of the electrospun beads. The observation of a stable plastron layer even when the surface is submerged under PDMS is extremely unique and indicates that the surface does not reconfigure, even when exposed to an enthalpically favorable solvent."

    --
    "FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."
  14. Re:Exterior coating for condoms? by hey! · · Score: 2

    I work in a porno shop and probably get laid way more than the entirety of the /. population combined.

    I can well believe both your assertions, but fail to see how they are connected.

    --
    Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
  15. Re:ugly words! by sco08y · · Score: 4, Informative

    phobicity? ...philicity?

    weren't phobia and ...philia good enough already?

    Foophobia is the fear or hatred of foo. Foophobicity is the degree of fear or hatred of foo.