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A Liquid That Turns Solid When Heated

Posted by timothy on from the ye-canna-break-th'-laws-o-physics dept.

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."

14 of 450 comments (clear)

  1. Weird, but cool! by lesterchakyn · · Score: 5, Funny

    This is one of the things that makes you think if everything is as you know...

    The Matrix anyone?

  2. what it says by pbranes · · Score: 5, Insightful
    What it says:

    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.

  3. Now we can buy by Wizzy+Wig · · Score: 5, Funny

    a bag of "Hot Cubes" to keep the coffee warm.

    1. Re:Now we can buy by Anonymous Coward · · Score: 5, Funny
      organic chemicals + you = death
      Therefore,
      you = death - organic chemicals
      That doesn't seem right. Surely you meant
      you - organic chemicals = death
      Anyway,
      me - coffee = death
  4. Heat shield? by BigZaphod · · Score: 5, Insightful

    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
    1. Re:Heat shield? by novakyu · · Score: 5, Informative
      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?

      That would probably depend on the property of the solid that forms when the solution is heated (is it a good insulator? what are its structural properties?), but I can think of one related application: temperature-controlled switch.

      The solution is transparent to visible light, whereas the solid that forms is not. Since this process depends on the temperature and is reversible, it's very simple to design a circuit (using a LED and phototransistor or some sort of photo-detector) that works as temperature-dependent switch. From what the article says,

      The temperature at which it becomes a solid falls as the concentration of CD increases.

      it should be possible to tweak the turn-on temperature to a degree.

      But then, this is not anything new--as far as dependence on temperature goes, there are many other materials that are probably more reliable (the only thing novel about this would be that its dependence is backward.)

      Back to the topic, yeah, it can probably be used as heat shield in a limited capacity: i.e. if it turns out that the liquid is transparent to infrared radiation while the solid isn't, this can be used as natural temperature-controlled infrared radiation shield (but of course, it will still be subject to heating due to other methods, like...conduction via the solid itself, unless the resulting solid turns out to be similar to styroform).

  5. Gets hard when you heat it? by garyisabusyguy · · Score: 5, Insightful

    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
  6. Missing some info here by Hockney+Twang · · Score: 5, Interesting

    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.

    1. Re:Missing some info here by DavidTC · · Score: 5, Interesting
      At 0 degrees Kelvin, it's not anything. It's just, in theory, a bunch of suspended frozen stuff that's exactly where it was before you hit 0. It has no chemical properties, because there is no way to do any sort of chemical interaction with it.

      That's in theory, of couse, since you can't hit 0 degrees Kelvin.

      But assuming you mean 'near 0 Kelvin', like d00ket pointed out, things get really weird down there. Some substances don't appear to have freezing points, there is no state below 'liquid'...they just move slower and slower. And some freeze quite normally, then do another transition way down there where they move back to a liquid like substance.

      The substance in the article is interesting, but not completely amazing. Various 'states of matter' are just rules of thumb.

      --
      If corporations are people, aren't stockholders guilty of slavery?
  7. Re:speculation on applications? by theAedileDecimus · · Score: 5, Funny

    I can just imagine it now...

    You go to Target to buy a 12-pack of "One-Time Use Thermometers."
    Instructions: "When the temperature is between 45 and 75 degrees celcius, the liquid inside turns to a solid, shattering the glass! That's all there is to it!"

  8. Useful material to have when printing out organs by Billy+the+Mountain · · Score: 5, Interesting

    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.
  9. Re:speculation on applications? by TWX · · Score: 5, Funny

    I think that my girlfriend is comprised of this stuff. She seems to suddenly turn frigid as soon as things heat up...

    --
    Do not look into laser with remaining eye.
  10. Re:Cookie dough batter by exick · · Score: 5, Funny

    On my planet, cookie dough batter is already a solid.

  11. Re:Application: Construction of Skyscrapers by wash23 · · Score: 5, Informative

    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.