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On your car windshield, ice is a nuisance. But on an airplane, wind turbine, oil rig, or power line, it can be downright dangerous. And removing it with current methods—usually chemical melting agents or labor-intensive scrapers and hammers—is difficult and expensive work.
But a new durable and inexpensive ice-repellent coating could change that. Thin, clear, and slightly rubbery to the touch, the spray-on formula could make ice slide off equipment, airplanes, and car windshields with only the force of gravity or a gentle breeze.
Researchers say the discovery could have major implications in industries like energy, shipping, and transportation, where ice is a constant problem in cold climates.
The coating could also lead to big energy savings in freezers, which today rely on complex and energy-hungry defrosting systems to stay frost-free. An ice-repelling coating could do the same job with zero energy consumption, making household and industrial freezers up to 20 percent more efficient. The paper is published in the journal Science Advances [open, DOI: 10.1126/sciadv.1501496].
Essentially, the rubbery coating jiggles and shakes the ice off.
University of Michigan source.
(Score: 3, Informative) by Anonymous Coward on Wednesday March 16 2016, @01:19AM
As far as I remember the problem with current coatings is their life expectancy. The ice slowly damages the surface of these coatings, eventually degrading the iceophobic abilities. The dangerous part of that comes when the water/ice then comes into contact with food or water. The non-stick coating used in many ice makers will slowly come off and make your ice taste horrible. Id imagine you would need a perfectly smooth surface with imperfections smaller than the size of a couple water molecules. The re-ordering of water from its liquid (or vapor form) to solid form increases its volume. If the water is on the surface before it freezes, some of the ice will literally "wedge" itself into the microscopic surface imperfections. If those imperfections are large enough the expanding freezing ice may cause some bits of the surface to flake off from the expanding ice. A similar process goes on at the macroscopic scale with asphalt roads. In freezing climates, liquid water flows into the surface cracks and when the temperature drops low enough the water freezes, widening the cracks further. This process will eventually lead to the total destruction of the road, and similarly microscopic coatings suffer similar degradation. I would imagine that only a perfect surface that ice can't find a way to push on (one where surface imperfections are small enough that water molecules can't get between them to exert force).
Or maybe I'm way off base, I have been drinking cold medicine like water it seems lately and im sure the virus inside me isn't helping.
(Score: 0) by Anonymous Coward on Wednesday March 16 2016, @01:29AM
https://www.erowid.org/chemicals/dxm/ [erowid.org]
(Score: 3, Informative) by c0lo on Wednesday March 16 2016, @02:20AM
What's your primary goal? Prevent ice sticking your objects or making ice (and the ease of getting it out of your tray is a "nice to have" feature?).
In any case, some of their surfaces (the best performing) were prepared from silicone rubber (PDMS [wikipedia.org]) with various percentages of silicone oil - normally, both of them don't have any specific taste, are non-toxic and pass unaffected through your guts.
In regards with durability, their best surfaces retain their properties up to about 10 ice/deice cycles, after which they tend to lose them - not a problem if your goal is to have ice-shedding surfaces (just recoat them).
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford