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A Liquid That Turns Solid When Heated
Roland Piquepaille writes "There are some sure things in life, such as death and taxes. When you are heating a solid, you expect it will melt and when you're boiling water, you're pretty certain that it will turn into vapor. But what about a liquid that becomes solid when it's heated? Of course, it has already been done, for example in the chemical process of polymerization. But now, PhysicsWeb writes that a team of French physicists has discovered a law-breaking liquid that defies the rules. When you heat it between 45 and 75C, it becomes solid. But the process is fully reversible, and this is a world's premiere. When you decrease the temperature, this solid melts and turns again into a liquid. I'm not sure of the implications of such a phenomenon, but it's fascinating. Read more for essential details."
This is one of the things that makes you think if everything is as you know...
The Matrix anyone?
Plazanet and colleagues prepared a liquid solution containing a-cyclodextrine (alpha-CD), water and 4-methylpyridine (4MP). Cyclodextrines are cyclic structures containing hydroxyl end groups that can form hydrogen bonds with either the 4MP or water molecules.
What I see:
And if you expect me to tell you how this discovery will modify our lives, you're going to be disappointed. I've not a slightest idea about it, even if I find fascinating that scientists always find new ways to break rules and shake our certitudes.
so what could the application of such a material be? a new breed of thermometers are on their way, i guarantee it.
thermometers for the 21st century and beyond.
In other news:
Cookie dough batter turns to solid in oven when heated. (Yeah, yeah, it's not reversible...)
No references to Ice nine?! I must be getting old.
If someone says he and his monkey have nothing to hide, they almost certainly do.
Fascinating stuff. This physics marvel of a liquid is a mixture of many separate elements... including milk, flour, eggs, sugar, and a pinch of salt.
The French have been freezing up when things get heated for years.
a bag of "Hot Cubes" to keep the coffee warm.
You're confusing expansion with turning solid. Water is one of the few (only?) substances that expands when it freezes.
So...if you were to put this in someone's bloodstream with the right concentration, you could cause it to solidify once it reached standard body temperature...
You know you've lost it when you begin signing physical documents with =^_^=
Hell has officially frozen over now.
I don't know much about physics, but could something like this be used as a heat shield of some kind? Like, where the shield is basically considered turned off when it is in the liquid state. Then when it hits a certain overload temperature, it turns to a solid and thus blocks (some of) the heat exchange?
Hexy - a strategy game for iPhone/iPod Touch
Why do I see a new line of sex toys being based on this?
;)
Or at least a splint that packs down small but that remains rigid when in contact with a warm body.
Um.. Maybe that would apply to a sex toy
Wherever You Go, There You Are
For your mohawk?
Win a signed Stephen Carpenter ESP Guitar from the Deftones: http://def-tag.com/?r=0008781
I think I've been drinking this stuff out of the coffee pot in my office for several years now.
I'm laughing at clouds.
No. That law in the strictest sense only applies to pure substances.
It's a solid at those temperatures, what is it at higher temps? Liquid again? Does it have two melting points? At what temp does it vaporize? Does it freeze at some point below the normal low-end melting point? At 0 degrees Kelvin, it's definitely a solid, somewhere above that, a liquid, then a solid again, then a liquid again, then a vapor? Maybe.
Get ready for the soon to be classic -cyclodextrine in the oilpan trick.
*Splort*
Isn't this how "The Andromeda Strain" did it's dastardly work? Turning the blood into a solid crystaline polymer?
I remember either Porsche or Volkswagen having a limited slip clutch that consisted of two perforated disks set next to each other in a container of special goo. If the wheels slipped it caused the disks to rotate at different speeds and the friction caused enough heat to turn the goo solid. I can't remember why they quit using it but it was more than a few years ago. I think it was going into their 4 wheel drive race cars. Just a memory though I got no hard data. Anyone know more about this?
Which law would this be? The one that says solids melt into liquids at higher temperatures? Oh wait, there is no such law - thanks to something called Sublimiation where solids go straight to a gas (like dry ice).
This is not an example of a new found element with impossible thermal properties. This is an example of materials and molecular chemistry in action. This works because it follows the laws of physics.
Reverse melting has been known for a long time.
People have been studying vortex systems that
do that. This is only new because it's a chemical
compound (rather than say electrons) that does this.
No physics breakthrough here. Maybe chemical
engineering breakthrough but that's it.
I wonder if it would be possible to change the temperature at which it re-liquifies, and if it becomes harder or more dense at higher temperatures. Seems like if that were the case, it would make for a good tiling material for the skin of a space shuttle
I vote for a new "Roland Piquepaille" section, he should get a good amount of advertisement revenue from his daily submits, always with "read more" links just quoting the original story.
"It's too bad that stupidity isn't painful." - Anton LaVey
Plazanet and colleagues prepared a liquid solution containing ?-cyclodextrine (?CD), water and 4-methylpyridine (4MP).
Is it edible?
Damn you hydrogen bonding, damn you shaking up our worlds with your heat freezing solids.
I sure hope it's non-conductive so I can put it as a coolant in my computer. Computer gets too hot, it turns solid and the computer "locks up". Ha!
Seriously though, if this stuff interacts well with other substances (i.e. doesn't explode, melt, send it to another dimension) then it could feasibly have applications where it would solidify around objects once they got too hot, thereby stopping their motion. And since the article says you can adjust the solidifying (freezing?) point based on its concentration, it could be tailor-made for different devices. This probably won't happen though because I'm guessing this stuff is probably expensive to make and does who-knows-what to human tissue
i hotdog.
Not that I can read the article yet (due to slowness), but the summary doesn't say what happens after 75C. It might melt again and that would be bad. If true, this chemical will possibly force the scientific community to reevaluate chemical laws and make new, more general (and therefore better) ones.
Slashdot is proof that Sturgeon's Law applies to mankind.
This article describes a similar material that is liquid below 20 C and solid above 32 C. Medical researchers hope to use it if they are able to perfect 3D printers that generate organs by spraying cells onto a substrate. The gel is used to reserve open spaces for blood vessels. Once the organ has been formed they cool it and the solid turns to liquid and runs out.
BTM
That was the turning point of my life--I went from negative zero to positive zero.
Placing the solid into my fridge, and again forgetting it for say, 2 or 3 weeks, reduces the solid back into a liquid.
Though I havn't personally tried it, I'm fairly certain that if I were to return the liquid back to the oven, and again properly forget about it, that I would again get a solid.
You talk as if fire is a real threat to reinforced steel skyscrapers. Prior to 9/11 there had never been a case of fire causing a skyscraper collapse. In fact, there was not even a real investigation proving that fire caused the 9/11 collapse; the steel was immediately shipped to Asia for scrap metal. So, since fire is not a big threat to skyscrapers why waste money trying to incorporate a new, unproven and likely expensive technology into steel skyscraper construction?
The rules of freezing, melting and vaporising (yes, I missed out sublimation) are not broken here. Chemists have known for some time that certain reactions can both only take place at a certain range of temperatures and reverse outside that range. This stuff does not freeze. It simply undergoes a reaction which bonds two types of molecule together to form a cohesive structure. The "normal" rules still apply to both compounds, but the new compound has a higher freezing point. That the reaction to form the new compound is reversible is also nothing new.
Analogy: Water freezes at 0 degrees Celsius, sodium chloride (salt) much higher at 804 Celsius. Add the two together to form an aqueous solution of sodium chloride and it lowers the freezing temperature, contrary to the properties of both substances. Heat it, and evaporate the water off and you end up with solid NaCl.
Sorry, but this has been hyped beyond recognition.
Resistance is futile. Reactance buggers it up.
Warning, this Roland fellow submits (and they get accepted!) stories all the time, which link to his personal blog site. All his posts have the same format. Stop feeding him page views!
I want to delete my account but Slashdot doesn't allow it.
Secondly, based on the types of compounds in the solution, and the description in the article, the "solid" is probably more of a waxy/jelly sort of substance.
That said, your idea could be made to work in other cases. I wonder if maybe the substance could be altered for use as a variable damping material for suspension or acoustic purposes.
Can someone explain the phrase 'sol-gel'? Does that mean that it become more like a gelatinous subject when heated instead of a more 'solid' solid?
Sols aren't solids. A "sol" is a colloid solution, so is a gel. Without getting too deep into the chemistry, he's basically saying it's a gel.
(Look up 'sol', 'gel', 'dispersion' and 'colloid' for more details)
First, the World Trade Center collapsed because jet fuel burns extremely hot. The WTC design was actually far stronger than most other skyscrapers standing today. Notice that the building survived the initial impact of a plane, and that it wasn't until later, when the intense heat of the burning fuel had time to weaken the steel support structure that it collapsed. A normal building fire would not have threatened the structural integrity of the WTC because there was nothing in the WTC that was hot enough to melt the beams, until the plane, full of fuel, arrived.
Second, I didn't notice in the article whether the volume of the material expands or contracts when it turns solid. If the hollow beam is partly filled with liquid (because the liquid expands when frozen) then there isn't necessarily enough contact between the liquid and the burning sections of the building to protect the upper portions of the beam. The beam will conduct some of the heat to the liquid, but depending on where the fire occurs in relation to the beam, the top of the liquid might freeze first, leaving the upper portion of the beam hollow. If the liquid contracts when frozen, you end up with a partly filled beam, which isn't necessarily stronger than a beam with nothing in it.
This leads to the third point, that nothing is mentioned about the structural properties of the liquid when frozen. Steel behaves extremely well under tension, and concrete under pressure. Thus, they complement each other quite well (which is why we make buildings out of them). Would the liquid make a better replacement for the steel, or the concrete? And would it perform equally well when the building is not on fire? Has having liquid-filled cavities in the building strengthened or weakened the structure, for the large majority of the time?
Finally, does the cost of using a material like this justify it? It's new, it probably costs more than steel to use in a building. Wouldn't redundant support structures be more reasonable? Or, using a design like the WTC, which I noted only failed from the heat of burning jet fuel?
I remember reading somewhere about making a bullet proof suit for soldiers where the suit was in fact hollow and filled with a gel containing nanoparticles. This thing might help us make more efficient ones: when the bullet hits the gel, the pressure is going to make it increase in heat, isn't it? So as the bullet tries to penetrate, it's going to get harder and harder... thus absorbing a HUGE amount of energy. Once the bullet is fully stopped, the pressure disappears, the temperature goes back down to normal and you have a liquid armor again. One problem is keeping the liquid from spilling out of the holes the bullets make... But I'm quite confident that can be overcome with some brilliant imagination. Of course, the real problem is how breakable is the solid formed? Because if the bullet goes straight through the hard material, then there's not point. But I think that'd be one use of this...
---- I am certain of only one thing : I know nothing else.
Too much Calvin & Hobbes, I suppose.
See, that's what I tried to tell the judge...
Check out http://www.solgel.com/educational/glossary.htm/ and http://www.chemat.com/html/solgel.html/
Its basically a more refined process of distilling out a liquid from a solution, and getting a solid out. However this new solid has chemical properties of both parts of whatever was in the solution. It allows for things like low-temperature glassmaking.
Literally a "sol-gel" is just a solid that still has some of the properties of a liquid/fluid such as flowing and free atomic relocation, but is much closer to a solid then a traditional fluid. This however does not make it a "jelly" or a "gel" its chemically, as well as physically distinct.
Medevo
It doesn't break any law, it follows every law. Physics around phase-changes (liquid-solid, gas-liquid, gas-solid) can be really weird. Iodine sublimes (goes from solid crystal form to gas with no intermediate liquid form) for example, at least at STP.
:-)
:-))
It's almost certainly those pesky hydrogen bonds - they're responsible for just about everything interesting in organic chemistry... Strange how things ultimately come down to geometry
It is new and strange, but I'd be willing to bet just about anything that the physical laws of energy conservation, attraction and conversion are being rigorously adhered to
Simon
Physicists get Hadrons!
To a physicist the phase diagram is interesting, because the solid/gel must have a larger entropy than the corresponding liquid. (Remember that you calculate equilibrium by minimizing the Gibbs energy G = H - TS).
Anyway it has been known for many years that some triblock polymers form gels when heated, but perhaps the solid phase of this new liquid is "more solid". Perhaps the news is that the liquid has a larger enthalpy of melting. I don't know
After reading the article (the actual publication, that is), here's an attempt at a summary.
When you heat something, the entropy (disorder) of a system increases in importance. This is a law of thermodynamics.
A gas has greater entropy than a liquid, both have greater entropy than a solid. Usually.
Now, this substance turns solid when you heat it. -This means the solid phase has higher entropy than the liquid phase. That is unusual, but it doesn't violate any laws.
How does it work? Well, it appear the alpha-cyclodextrin molecule has two conformations (shapes). In the low-temperature one, it hydrogen-bonds to itself. At higher temperatures, these bonds are broken. (this is what happens with ice-water-steam too)
The funny thing about this substance, is that once these internal hydrogen bonds are broken, it allows the molecule to bind to other ones.. so while you break the "internal" hydrogen bonds, you give rise to a bunch of "external" molecular bonds, to other alpha-cyclodextrine molecules.
This leads to the formation of a solid. (not actually a true solid, but rather a 'sol', a suspension of linked-together alpha-Cyclodextrin molecules in water) And this solid actually does have lower entropy than the liquid phase, due to the breaking of the internal hydrogen-bonds.
No laws broken. Nothing 'impossible' going on. But, it is however an interesting phenomenon, and something which certainly may turn out to have practical uses in the future.
Shock absorbers. This stuff would make fantastic shock absorbers.
Reinforcement for solid structures. Somebody already mentioned skyscrapers, but I'm also envisoning other more improbable structures, like hurricaine proof buildings. Wind blows, soften up the beams and let her bend a bit. Wind stops, stiffen the supports back up.
Mecha. This has to be used in mecha. Beams that can bend a bit, be solid or fluid, would be excellent in 50 foot killer robots. You know it.
Tank armour. Make it solid and when stuff hits, it breaks. Change temperature, and it melts. Change temp again and it becomes solid again, with no signs of previous damage. Regenerating armour.
Weaselmancer
rediculous.
Well,it's amazing, but it's not the first time i see it.
I work in molecular biology. Recently we started doing experiments with so-called Matrigel. This is purified extracellular matrix from mice tumours. It's a natural environment to grow endothelial cells and study the development of blood vessels. This is by no means a mysterious substance - thousand of labs buy it and use it every day.
Well, Matrigel works exactly the same way the substance in the article does. It is fluid around 0, but rapidly freezes at -20 and rapidly becomes solid at room temperature. And it is fully reversible. This also makes the substance a bitch to manipulate -you pick up with the pipette,and it becomes solid inside the pipette before you can transfer it!
Still, it is amazing to mimic such a behaviour in a simple solution instead than in the tremendous proteins-and-sugars mess that's Matrigel.
-- Patent no.123456: A way to personalize
That's rather short sighted, don't you think? This one particular substance happens to break our elementary perceptions of The Way Things Work in a very specific way. It's likely a really small step beyond that to move the temperature range up, down, wider, thinner, etc.
Read jack phelps dot net
The best option over the above (and a common upgrade) is the fully-mechanical "Torsen" ( torque-sensing ) differential.
Quaife makes one of these. An all-wheel drive car would need three, and at around $1k a pop they aren't exactly cheap, but they have a lifetime warranty.
I was hoping something more interesting and subtle was going on. Of course, it will still liquify above 75 degrees or whatever the melting temperature is for the hydrogen-bonded network of the two compounds... Maybe you could make some kind of antilubricant out of a similar compound though: increase friction / viscocity as the temperature increases. Not sure what that might be useful for though - slowing down a flywheel when a machine starts to overheat?
"Body heat activated - when the temperature rises, it fuses your arms to your sides so that you can't release any bad armpit smells"
OK, I'm just spitballing here.
Perfectly Normal Industries
It most certainly would melt again after 75C; it's just a hydrogen-bonded organic solid at that point, and hydrogen bonds are weak and only partially-covalent and would easily melt at moderate temperatures.
William Langewiesche in his _American Ground_ set of Atlantic Magazine articles (Aug-Oct 2002) writes that it wasn't so much the jet fuel that caused the collapse of the towers, but all the paper inside them. It's been a while since I've read the articles, so I don't remember all the particulars, but dig them up if you are interested in the scenario.
hot enough to melt the beams
Even with jet fuel it wasn't enough to melt the steel. The problem is that steel loses much of it's strength at high temperatures, making it liable to bend or snap under load.
Also, and I relize your are replying to someone else's idea here, but I fail to see any logic in using this stuff in construction. What possible benefit is there in having the material be liquid at low temperatures? Instead of adding this stuff "in case of fire" you're better off using some ordinary building material that will be stronger at both low and high temperatures.
-
- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
It's a little bit O/T, but there is no point pursuing the liquid-filled beam/column idea - there are much, much better ways (read : both cheaper *and* more effective) of fire-protecting steel.
The basic issue, as you note, is that steel loses flexural strength at an alarming rate when heated. At 500degrees C, the flexural modulus is reduced over 50%, and that's enough to destabilise structures - after which loads get concentrated, and progressive collapse ensues. No need for actual melting.
So: how to keep structural temperatures down. There are a few basic approaches. One, occasionally used when the steel is BIG, is just to rely on Hp/A: if the exposed surface area is small compared with the cross-section, the rate of heating will be acceptaby low. The second is insulation: either a spray-on insulating coating (usually vermiculite-based), encapsulation in concrete, or enclosing with insulative board materials. There are also intumescent coatings, but these are expensive, and so limited to areas where the steel is exposed for aesthetic reasons - lobbies and the like. The third, proposed here, is essentially filling the structure with liquid. But a polymer like this, apart from expense, is never going to abstract enough heat to do any good. There is are only two structures I know of which do this, both exposed tubular structural members: the Cannon Stret office building (Ove Arup & Partners, London, 1973) and the Swiss Re building (Foster & Partners, London, 2003). In both cases the fluid is water with anti-corrosives and a bunch of other chemicals, and is continually pumped. Not cheap, but only water has a high enough specific heat capacity to be useful.
Note further, the point of fire protection is NEVER to save the building. The *only* criterion is to buy time to get people out, and safe. The building can fall, indeed should - after a major fire there will be all sorts of latent damage that could endanger future inhabitants. The two coincided at the WTC: it wasn't just the extraordinary fire load that brought the building down - but the impact which shook loose flaky insulative materials, fatally exposing the (lightweight floor) structure to high rates of heating.
Can this stuff be used to line condems?
Every one at slashdot thinks they understand science because they think of themselves as geeks. I say it is not being a geek that makes you a scientist, but being a scientist makes you a geek. This story is a perfect example. Some material does something that we would not expect based upon our own observational experience, but since we "know science" it must violate all of our accepted scientific ideas. Its really funny if you don't take it serious. Seriously it must show that our educational system has doen such a poor job of explaining the basics of the scientific process and/or that we'd rather make fools of ourselves than admit that we don't know everything.
Well.. maybe. Or Maybe not. But Definitely not sort of.
I'd recommend some sort of radio-isotope clad in stainless steel. Self heating.
Plus if you hold your coffee cup between your legs in the car it could give your future children an opportunity for advantageous mutations. Of couse they could also turn out to be complete freaks but these days they're likely to turn out to be complete freaks anyhow so it is not like anyone would notice.
This is not novel. This polymer just happens to form weak bonds, as opposed to disulfide, vinyl, ester or other types of strong bonds typically associated with polymers. That's the neat part - they're mostly reversible.
There exists no way of exchanging information without making judgments. --Bene Gesserit Axiom
In a word, NO.
At best it proves how little we understand that law, but there's nothing to say the entropy wasn't balanced by the energy transfer involved(all physical condensations, straight from gas to solid would be a lot worse from a disorder aspect, without factoring the energy involved), and it's quite likely the math will bear this out(but I'm too lazy to do this math).
It also shows how an instinctive understanding of physic laws can lead to misunderstanding those laws. I'm sure someone tried to invalidate a few physics laws when we discovered water actually increased volume when heated from 4 degrees celsius to 0 degrees celsius too. Turned out the law was perfectly fine, as long as you interpreted the whole thing, with the phase change graphs and triple-points, and not just the instinctive understanding: heat it and it expands, then becomes liquid, then expands again and becomes gas.
Trying a simplification of the law, finding it doesn't work, doesn't necessarily mean the law isn't good, it might just be a bad simplification, after all.
No need; conceptually it's easy enough: each of the aCD moledules gets bent out of shape by the heat, thus exposing more sites for hydrogen bonds to form, allowing the solidification to occurr. Since these molecules are capable of snapping back into the previous shape when cooled, they are therefore storing energy. And so the solid is still in a higher-energy state than the liquid.
"Orthodoxy is unconsciousness" - Orwell
If "cooperate" means that we have to believe it when you folks say it - then never. We always check.
How many beans make five, anyhow ?