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.
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A University of Michigan researcher has created a coating that could be used to repel water, oil, and other substances:
In an advance that could grime-proof phone screens, countertops, camera lenses and countless other everyday items, a materials science researcher at the University of Michigan has demonstrated a smooth, durable, clear coating that swiftly sheds water, oils, alcohols and, yes, peanut butter.
Called "omniphobic" in materials science parlance, the new coating repels just about every known liquid. It's the latest in a series of breakthrough coatings from the lab of Anish Tuteja, U-M associate professor of materials science and engineering. The team's earlier efforts produced durable coatings that repelled ice and water, and a more fragile omniphobic coating. The new omniphobic coating is the first that's durable and clear. Easily applied to virtually any surface, it's detailed in a paper published in ACS Applied Materials & Interfaces.
Tuteja envisions the new coating as a way to prevent surfaces from getting grimy, both in home and industry. It could work on computer displays, tables, floors and walls, for example.
[...] Ultimately, the team discovered that a mix of fluorinated polyurethane and a specialized fluid-repellent molecule called F-POSS would do the job. Their recipe forms a mixture that can be sprayed, brushed, dipped or spin-coated onto a wide variety of surfaces, where it binds tightly. While the surface can be scratched by a sharp object, it's durable in everyday use. And its extremely precise level of phase separation makes it optically clear.
Just what I needed for my keyboard, VR headset, countertop, toilet bowl, 1 gallon mayonnaise jar, t-shirts, patio deck, sailing ship, the inside of all of my body's cells, and synthetic killer bacteria.
Smooth, All-Solid, Low-Hysteresis, Omniphobic Surfaces with Enhanced Mechanical Durability (DOI: 10.1021/acsami.8b00521) (DX)
Related: Nissan Testing 'Super-Hydrophobic' and 'Oleophobic' Paint
LiquiGlide Slippery Coating Coming Inside Norwegian Mayo Bottles
Spray-on "Repellent" Could Make Freezers Frost Free
(Score: 2) by Nerdfest on Wednesday March 16 2016, @01:03AM
I've always wondered if hydrophobic coatings would help keep ice from forming. I'm sure someone has probably tried them.
(Score: 4, Informative) by c0lo on Wednesday March 16 2016, @02:02AM
They tested it: the result is that superhydrophobic surfaces tend to act as icephobic as well:
The Science Advances FA is CC licensed.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 0) by Anonymous Coward on Wednesday March 16 2016, @01:06AM
> could make ice slide off equipment, airplanes, and car windshields with only the force of gravity or a gentle breeze
How about roads in the deep South?
(Score: 1, Insightful) by Anonymous Coward on Wednesday March 16 2016, @03:09AM
That would defeat the purpose of roads - cars would also slide off a low-friction surface.
(Score: 2, Insightful) by Anonymous Coward on Wednesday March 16 2016, @07:58AM
The other AC is incorrect, tire-friction is not the same as water/ice friction as this story demonstrates by describing the coating as rubbery.
BUT, the reason stuff like that is not useful on roads is because all the tire-friction will rub it right off the road sufrface pretty quick.
(Score: 3, Insightful) by vux984 on Wednesday March 16 2016, @01:12AM
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.
I'm not sure the all applications they've suggested make a lot of sense. For example freezers... it doesn't really sound like it prevents the ice from forming, it just prevents it from sticking to things..."it slides of with the force of gravity or a gentle breeze"... so uh... it still forms and then builds up at the bottom of the freezer?
(Score: 2) by c0lo on Wednesday March 16 2016, @02:31AM
Do you imagine that, somehow, there exist a way to "convince" the water in cold air to not freeze and remain magically suspended in that freezing air?
Suppose that you have all the surfaces in your freezer which are so hydro/ice-phobic that no water will stick on them ever.
What do you think will happen with the water inside the freezer (the one that gets there with the air when you open the freezer and/or the one sublimating from whatever food you put in the freezer)?
In what aggregation state and in what place do you think you will find most of that water?
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by vux984 on Wednesday March 16 2016, @06:07AM
"Do you imagine that, somehow, there exist a way to "convince" the water in cold air to not freeze and remain magically suspended in that freezing air?"
Of course not, I presumed the "expensive defrosting" equipment that was mentioned in the summary are dehumidfiers of some sort that take the water in the air inside the freezer and removed it to the outside of the freezer; to prevent it from forming frost/ice in the freezer.
Now, as the summary says this defrosting equipment won't be needed now that we have hydrophobic spray... then, as you said, "where is the water in the air going to go?" That was essentially my question too.
(Score: 0) by Anonymous Coward on Wednesday March 16 2016, @08:08AM
> "Do you imagine that, somehow, there exist a way to "convince" the water in cold air to not freeze and remain magically suspended in that freezing air?"
I can imagine such a thing. A surface that interacts with ice crystals in such a way that they won't form unless the temperature is significantly below the normal freezing point. In which case I would expect frost to form on the surfaces of other items in the freezer, which might not be so bad depending how how long stuff is left in there.
In the best case the water vapor would condense as a liquid on that surface where it could be routed out a drain, as compared to a frost-free freezer that has heating elements underneath all the surfaces in order to melt the frost before draining it.
(Score: 0) by Anonymous Coward on Wednesday March 16 2016, @05:49AM
(Score: 2) by wonkey_monkey on Wednesday March 16 2016, @08:37AM
so uh... it still forms and then builds up at the bottom of the freezer?
Where it can be easily scooped out every day or two rather than having to empty the entire freezer every few months and wait for it to thaw.
systemd is Roko's Basilisk
(Score: 2) by richtopia on Wednesday March 16 2016, @10:38AM
Valid point, however I do not thing the applications will be affected by ice forming elsewhere.
For freezers, I could forsee putting this only on critical locations (particularly on industrial equipment). Defrosting coils is time consuming and prone to damage.
I can think of many non-freezer applications, although I suspect the freezer is the first use case as it is relatively protected and self contained. But imagine having this on aeroplanes - no more deicing on the runway. Or the windscreen of your car.
Also, depending on the optical characteristics of this coating, it could really help with protecting optics in rough environments. Watch youtube videos of high-altitude balloons, and you'll typically see ice forming, which gets worse as you get higher.
(Score: 3, Informative) by VLM on Wednesday March 16 2016, @12:06PM
so uh... it still forms and then builds up at the bottom of the freezer?
It forms on the food and stuff, at a substantially accelerated rate, because it can't form on the walls or presumably the evaporator coil.
Also lets be honest here, my fridge is pretty clean but I'm under no illusion its a surgically clean surface. Theres "gunk". Even just room air dust settling out. Some weird coating underneath a layer of dust or gunk, even if too thin to see, may as well not be there. In theory the ice wouldn't form on walls or WTF, but in practice it forms perfectly well on anything that hasn't been thru an autoclave in the last couple minutes, or anytime its not operated in a semiconductor clean room.
(Score: 2) by urza9814 on Wednesday March 16 2016, @09:49PM
This might just be a bad metaphor...but assuming it ISN'T, I don't see a small amount of dust and gunk causing a problem. They'll just "jiggle" with it.
But even if that doesn't work, I could see this coating keeping the freezer cleaner in the first place. What kind of "gunk" is building up? If it's something like spilled ice cream or sauce, it's mostly water so it shouldn't adhere to the coating very well. And dry dust can attach to the freezer wall, but then ice can attach to the dust, and since the ice can't adhere to anything else eventually the weight of that ice will pull the dust off with it.
(Score: 2) by Gaaark on Wednesday March 16 2016, @01:17AM
Now i can't get the picture out of my mind of girls in latex in Canada............ oooooohhhhh, mannnnnnn! ;)
--- Please remind me if I haven't been civil to you: I'm channeling MDC. ---Gaaark 2.0 ---
(Score: 2) by MostCynical on Wednesday March 16 2016, @01:59AM
Is twerking still a 'thing' in Canada?
"I guess once you start doubting, there's no end to it." -Batou, Ghost in the Shell: Stand Alone Complex
(Score: 3, Funny) by Anne Nonymous on Wednesday March 16 2016, @02:59AM
Well clearly it doesn't work as a repellent.
(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
(Score: 0) by Anonymous Coward on Wednesday March 16 2016, @11:35AM
We're geeks, we thrive on factlets! Having the implications spelled out is nice though.
I.e. is it some chemical compound or perhaps a nanomaterial or is it all just a big "trust us" secret?