A Liquid That Turns Solid When Heated 450
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."
what it says (Score:5, Insightful)
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.
Heat shield? (Score:5, Insightful)
Gets hard when you heat it? (Score:5, Insightful)
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
Weapons technology. (Score:1, Insightful)
I can imagine liquid armor in some sort of gel packs. Normally it would allow free movement to the wearer - but it would instantly turn solid from the energy of the impact when a high-speed projectile (eg: a bullet) tries to penetrate it.
Interesting..
Re:Application: Construction of Skyscrapers (Score:5, Insightful)
Re:What?! (Score:2, Insightful)
Re:Weird, but cool! (Score:4, Insightful)
This is one of the things that makes you think if everything is as you know... The Matrix anyone?
Ehhh. This is more what we know empirically. We're merely discovering a priori things that we weren't aware of previously. The Matrix was more about what we know epistemically.
Re:What?! (Score:1, Insightful)
It means you are someone who once kept up with pop culture, but stopped doing so for some reason.
Re:Now we can buy (Score:1, Insightful)
(They were a lot shorter in those days, weren't they?)
"dumb-it-down" soundbite phrasing (Score:5, Insightful)
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
Summary for non-chemists (Score:5, Insightful)
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.
Ok, here's what I can come up with (Score:5, Insightful)
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.
Re:Astroturf Alert! (Score:2, Insightful)
Is this really news? (Score:4, Insightful)
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.
Re:Application: Construction of Skyscrapers (Score:3, Insightful)
Re:Weird, but cool! (Score:1, Insightful)
Proteins tend to change form when you heat them, and even when cooled down, they remain the same (the proteins have re-folded).
Heat-sensitive Antilubricant? (Score:2, Insightful)
Re:Me too (Score:1, Insightful)
Except they aren't Roland's stories, they're plain rip-offs from serious sites. You know, to lure stupid fucking morons like you to his site for cheap page-views and advertising income. Every time you visit his site, YOU cause the internet to die a little bit as useful information is plagiarized, assraped and bent over backwards in the name of profit by some fuckwad SPAMMER. There is no other way to call Roland's endless stream of stolen articles.
Are you either really dense or really ignorant?
Re:Roland Piquepaille (Score:2, Insightful)
The fact remains that the stories and articles Ronald comes up with are genuinely interesting.
I don't see any of the whingers actually finding and submitting decent stories.
{/rant}
Re:Astroturf Alert! (Score:1, Insightful)
Re:Application: Construction of Skyscrapers (Score:5, Insightful)
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.
-
Re:Weird, but cool! (Score:4, Insightful)
Re:Weird, but cool! (Score:2, Insightful)
Re:Weird, but cool! (Score:3, Insightful)
However, a reversible transition in which a liquid becomes a solid when heated has never been observed until now (emphasis added by poster)
boaworm wrote:
Ever heard of a thing called an "egg"
I have in fact... but I have yet to hear of anyone un-cooking one...
Re:Weird, but cool! (Score:3, Insightful)
Reproduction. Mutation.
Re:Breaks the rules? (Score:3, Insightful)
If so then water turning into ice is "chemical manipulation" as well. When pure water freezes it forms the exact same sort of hydrogen bonds this new substance forms. In both cases those hydrogen bonds provide the attraction that overcomes the thermal motion of the molecules, freezing them in place.
It's the exact same process. The only difference is that in this new substance the hydrogen atoms are "hidden" towards the inside of the molecule at low temperatures and they swing outwards becoming available to attract neighboring atoms when the temperature goes up.
Hmmm, an interesting way to look at it is that at the lower temperature those hydrogen atoms and hydrogen bonds swing inwards and atoms from one part of the molecule "freeze" to atoms from another part of the same molecule, and that this self-self freeze effect overcomes and severs the normal intra-molecule freeze attactions. This freezing of motion within the molecule explains how you get the required lower net entropy at lower temperature, despite the fact the liquid phase motion of the molecule as a whole has a highter entropy.
-
Re:The French... (Score:2, Insightful)