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Science Technology

Plastic That Changes Shape In Light 123

JLavezzo writes "Picture a flower that opens when facing the sunlight. In work that mimics that sensitivity to light, MIT Engineer Robert Langer and his German colleagues have created the first plastics that can be deformed and temporarily fixed into shape by light. This material could one day lead to medical devices that build themselves inside a patient's body, or door latches that can be opened with a flashlight. Additional commentary available at The Science Blog"
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Plastic That Changes Shape In Light

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  • by Greg Wright ( 104533 ) * on Friday April 15, 2005 @06:48PM (#12250472) Journal
    They, the scientists, have been able to do this for some time with
    heat. The link below is to an article that shows a 30 gram weight
    being lifted and lowered by a type of polymer know as nematic
    elastomers.

    http://www.sciam.com/article.cfm?articleID=0007C 55 D-FA8F-1C5F-B882809EC588ED9F

    they also say in the above article(link) that, "..light can also induce
    shape changes anywhere from 10 to 400 percent [in the polymer]."
    However, it takes a hours for it to return to the original shape.

    One of the best applications,in my opinion, for any fast-acting shape
    changing polymer would be as artificial muscles. Not sure how
    practical or easy that might be. You would have to get the temperature
    range, where the shape changing takes place, down pretty low and find
    a way to control it outside of the body's heat influence. I am sure
    there are other problems as well.

  • by LiquidCoooled ( 634315 ) on Friday April 15, 2005 @06:49PM (#12250490) Homepage Journal
    I thought you couldn't light the inside your body.

    I was under the assumption that was the one place the sun don't shine.
    • That's it, they are coming out with plastic bullets shot out of a handgun. Which if used under the sun, becomes a giant cannon.

      • they already have plastic bullets..they would put hollow tips out of business with this new tech. they also have plastic guns, so much for airport security - you know thats why they decided to do it too.
    • That's precisely the sort of practical application this breakthrough is looking for! It should put an end to all those embarrasing "I was painting the ceiling in the nude and fell on this coke bottle" hospital visits.
  • by homer_ca ( 144738 ) on Friday April 15, 2005 @06:50PM (#12250494)
    No Flash Photography Please
  • doors? (Score:2, Insightful)

    by Anonymous Coward
    Why would you want a door that opens to light?
    • Why would you want a door that opens to light?

      I think you should ask Indiana Jones why he WOULDN'T want a door/trap/device that activates with light ;-)
    • And can't we have that already with "electric eye" technology, solar cells, etc. Not that this isn't pretty cool stuff.
    • Re:doors? (Score:3, Insightful)

      by BobPaul ( 710574 ) *
      The plastic only reacts to certain frequencies, and this is better than an electronic solution since it'll work when the power's out.

      It won't automatically open the door when the sun shines on it...

      Anyway, the door thing really just sounds like a semi-cool idea, not anything really marketable or practical...
      • only reacts to certain frequencies

        It won't automatically open the door when the sun shines on it...

        In order to do that, it would have to not open in the presence of certain frequencies - or in other words open when only certain combination of frequencies were applied to it. That's a pretty tall order and I don't think this technology is capable of that.

        Instead it would open in the prence of light or not. I'm not sure where the power is coming from for this?

        I don't see a practical use for this in door
        • How about windows that if left open at night close at dawn?
        • ... it shows that you didn't read the article

          In order to do that, it would have to not open in the presence of certain frequencies - or in other words open when only certain combination of frequencies were applied to it. That's a pretty tall order and I don't think this technology is capable of that.

          If you look right in the article it states:
          "The shape-changing ability is accomplished by attaching photosensitive molecules to a polymer. When exposed to ultraviolet light, the photosensitive particles beco
    • I like the idea of fridges that close when the light goes on. :)
    • I'd like some window blinds that opened to sunlight automatically without mechanical components please.
  • This material could one day lead to medical devices that build themselves inside a patient's body, or door latches that can be opened with a flashlight.

    Yeah, like Shrinky Dinks this'll be a hit with the mail-order or discount store crowd before you know it.

    People tend to forget what cyanoacrylate's first purpose was [nih.gov].

    • by mesach ( 191869 ) on Friday April 15, 2005 @07:00PM (#12250610)
      One of the first widespread uses maybe but not first purpose. It was used in medical means over 20 years after its invention.

      Pasted from the straight dope [straightdope.com]

      "Super glue, Krazy glue, Eastman 910 and similar glues are all a special type of glue called cyanoacrylates. Cyanoacrylates were invented in 1942 by Dr. Harry Coover of Kodak Laboratories during experiments to make a special extra-clear plastic suitable for gun sights. He found they weren't suitable for that purpose, so he set the formula aside. Six years later he pulled it out of the drawer thinking it might be useful as a new plastic for airplane canopies. Wrong again--but he did find that cyanoacrylates would glue together many materials with incredible strength and quick action, including two very expensive prisms when he tried to test the ocular qualities of the substance. Seeing possibilities for a new adhesive, Kodak developed "Eastman #910" (later "Eastman 910") a few years later as the first true "super glue." In a now-famous demonstration conducted in 1959, Dr. Coover displayed the strength of this new product on the early television show "I've Got a Secret," where he used a single drop placed between two steel cylinders to lift the host of the show, Garry Moore, completely off of the ground.

      The use of cyanoacrylate glues in medicine was considered fairly early on. Eastman Kodak and Ethicon began studying whether the glues could be used to hold human tissue together for surgery. In 1964 Eastman submitted an application to use cyanoacrylate glues to seal wounds to the United States Food and Drug Administration (FDA). Soon afterward Dr. Coover's glue did find use in Vietnam--reportedly in 1966 cyanoacrylates were tested on-site by a specially trained surgical team, with impressive results."
      • I've had doctors tell me that if you have a bad wound in need of stitches but you don't have anything handy, superglue it. It dries fast and strong, and while it may not be terribly accurate it will stop the bleeding. And like the superglue that gets on your fingertips, it eventually goes away on it's own.

      • You wouldn't happen to know Chacham, would you? I only ask because of your user ID and sig.
    • Uh, that article you link to was 1994, and said that Krazy Glue was tried for cardiac surgery. Krazy Glue existed long before 1994. How is this "first prupose"?

      Just wonderin'.
      • Uh, that article you link to was 1994, and said that Krazy Glue was tried for cardiac surgery. Krazy Glue existed long before 1994. How is this "first prupose"?

        Just a quick match. I knew even in the 60's they were using cyanoacrylate for open heart surgery, because of the necessity of sealing arteries quickly. My father worked in the chemical industry for 38 years and used it as an example, when trying to get something through my thick skull, of the many uses of various compounds.

  • WTF? (Score:3, Funny)

    by El ( 94934 ) on Friday April 15, 2005 @06:51PM (#12250517)
    door latches that can be opened with a flashlight.
    Right... 'cause we all want a door that opens itself every morning when the sun comes up!
    • Re:WTF? (Score:3, Interesting)

      by Mavakoy ( 730866 )
      Could be useful on farms, or if you have a dog in the house and don't want to crawl out of bed first thing!

      • Could be useful on farms, or if you have a dog in the house and don't want to crawl out of bed first thing!


        When you have a hammer, everything looks like a nail.

        A timer operated door would do the work much
        better & cheaper I think.

        Also in places like Seattle, the dog would be trapped forever if the door opening was dependent on the sun shining.
    • Windows (Score:3, Interesting)

      by phorm ( 591458 )
      No, but we might want a window that does. Have it close up on a cold night and open to a warm summer morning to let the fresh air in...
  • by YetAnotherName ( 168064 ) on Friday April 15, 2005 @06:52PM (#12250524) Homepage
    I had one of those Star Wars Speeders that fit Luke and Ben Kenobi action figures as a kid. It was all plastic. I accidentally left it on the dashboard of my mom's car during a sunny day.

    Sure enough, light changed its shape irrevocably.
  • clarfication (Score:5, Informative)

    by morcheeba ( 260908 ) on Friday April 15, 2005 @06:54PM (#12250543) Journal
    Just to clarify... this plastic changes shape in response to various wavelengths of light... not the quantity, as has been previously done [solardeathray.com]. (Note - the older technology has been adapted for cell phones, too [solardeathray.com])
  • by rookworm ( 822550 ) <horace7945@@@yahoo...ca> on Friday April 15, 2005 @06:54PM (#12250548)
    This could be the ultimate cure for geeks. Simply wear special plastic goggles that restrict vision (and hence computer access) if wearer does not go outside.
  • by Gadgetfreak ( 97865 ) on Friday April 15, 2005 @06:57PM (#12250569)
    Personally, I'd like some self-adjusting miniblinds.

  • Inside sources have confirmed that Longhorn will have a cool feature called 'irregular display'. If the use hits 'windows key + $ + ^ + F13' the screen would emit a low wave length light that will deform the monitor. You can preset the deformation patterns before hand. This revolutionary feature uses the 'plastic deformable by light' discovered recently at MIT.

    "This is a unique feature which will help us take on OS X Tiger" - Gates

    The only problem is that once deformed the monitors cannot be reverted to t
  • Odd examples. (Score:5, Interesting)

    by BigZaphod ( 12942 ) on Friday April 15, 2005 @06:58PM (#12250585) Homepage
    Why do these "gee whiz" stories about new tech or materials always have such strange example applications?

    "This material could one day lead to medical devices that build themselves inside a patient's body, or door latches that can be opened with a flashlight."

    Okay, the medical one isn't so bad (except, kinda dark in a body)... but a door latch that opens with a flashlight? Huh?

    How about...
    - Plastic flowers that open in the sunlight!
    - Sunglasses that automatically lower in front of your eyes!
    - Light-based transformer toys!
    - Gag sundials!

    Okay, maybe this is harder than it looks...
    • Chasitity belts!
    • Just think of the cool booby traps you could design
    • How about plastic displays that use light activation to make a solid display that requires no backlighting.
    • How about using this in medical implants: a body that changes shape when exposed to light! Imagine the possibilities...
    • Why do these "gee whiz" stories about new tech or materials always have such strange example applications?

      "This material could one day lead to medical devices that build themselves inside a patient's body, or door latches that can be opened with a flashlight."

      I don't know about you, but I've always wanted a door lock that a burglar could open just by shining a flashlight on it.... ;-)

      But seriously, the potential, assuming it can be done accurately enough and quickly enough, might be something akin t

    • by UserGoogol ( 623581 ) on Friday April 15, 2005 @09:34PM (#12251677)
      You have to appreciate the mind of a scientist.

      Scientist1: Dude, look at this plastic. When it comes in contact with ultraviolet light, the plastic forms bonds with itself, causing it to change shape.

      Scientist2: Awesome! If you hit it with another frequency, the proccess reverses itself.

      Businessman: Hm. What sort of applications do you think this could have?

      Scientist2: App-li-kay-shuns?

      Scientist1: Uh, you could make toys out of it. Or... maybe like you could have it bend into... uh... medical things. For medicine.

      Businessman: I'm cutting your funding.

      Scientist1: WHY DON'T YOU LOVE ME?!?
    • Why do these "gee whiz" stories about new tech or materials always have such strange example applications?

      When kept in a woman's purse, a, ahem, "toy" remains small. When brought out into the light, it grows.

      Then when inserted, it is dark and... oh nevermind.
  • Just think about the dash on the clunker you drove in high school.
  • Cool stuff, but:

    or door latches that can be opened with a flashlight.

    Why the hell would that be a good idea?!
  • Real doll when you have visitors over, but when the lights turn off at night she transforms like cinderella.
  • by ZombieEngineer ( 738752 ) on Friday April 15, 2005 @07:23PM (#12250812)
    This could allow retail level solar panels to eek out the equivalent to an additional 2 hours of peak sunlight over a 12 hour period. Initially this would appear to be a 10% improvement but in reality it is closer to a 30% improvement (I will leave it as an exercise for the reader to integrate sin(x.pi/12) from 0 to 12 hours [flat panel on the ground with the sun passing directly overhead] to yield 6.28).

    I should imagine the cost of the plastic is going to be far less than the processed silicon for solar cells.

    da ZombieEngineer
  • Other related work (Score:5, Informative)

    by karvind ( 833059 ) <karvind.gmail@com> on Friday April 15, 2005 @07:36PM (#12250915) Journal
    Another field where MIT work can be useful is space antennae. Here an optical signal would initiate a sequence of changes in the shape, causing the antenna to refocus on a different point in space.

    OSU had developed light-tunable plastic magnets [osu.edu]. Here the plastic material becomes 1.5 times more magnetic when blue light shines on it. Green light partially reverses that effect.

    Another interesting work is from PSU on PLZT [psu.edu], this new material shows a large piezoelectric effect in response to near-ultraviolet light. Piezoelectric materials convert electricity into mechanical energy -- movement. When an electric current is run through piezoelectric ceramic, the ceramic changes size -- it shrinks or expands. Certain ferroelectric materials exhibit stronger photovoltaic (light into electricity) effects. Combining these ferroelectrics with piezoelectrics (electricity into motion), researchers created a single material that would convert light directly into motion.

  • Some other uses (Score:1, Interesting)

    by Anonymous Coward
    CD that unwraps itself

    Condom that changes color according to your mood.

    All of these wonderful features with only one piece of plastic. Flashlight not included.
  • by KipCas ( 872321 ) <{moc.oohay} {ta} {pik2y}> on Friday April 15, 2005 @07:55PM (#12251082) Homepage
    Well, my wife does. It can sort of shapeshift. It is plastic as well and if anybody but me or her see it it becomes a "Back Massager".
  • Now we need plastic that will change shape when exposed to dark :)

    Close the door! You're letting the dark in!

  • Joke Sundials, anyone?
  • by _ph1ux_ ( 216706 ) on Friday April 15, 2005 @08:11PM (#12251199)
    I have met some women who have faces made out of this stuff. Unfortunately I had to find out the hard way.
  • Now you don't have to blame the alcohol when you say she looked different because of the low lighting.
  • YES! Now, instead of turning a doorhandle, I can reach into my pocket and turn on a flashlight. I can't wait to buy the batteries.
    • ... and in related news yet another starvation death due to dried out battery power. Doorhandle pressure groups reacted outraged, but since flashlight lobbyists can shove heaps of cash towards legislators nowadays, a ban on flashlight operated doors has once again been rejected.
  • I find it hard to believe that no /. ers or BoingBoingers mentioned the similarity between this polymer and Pynchon's legendary Imipolex-G - the erotic (as clothing and/or weaponry) polymerproduced in Gravity's Rainbow.

  • ... and then, when nanotechnoly is thriving, they will come up with something so small, thin and cheap that will make every geek go nuts: a key.
  • Plastics.

    OK, it sucks, but it's 7:30AM on a saturday and I'm stuck working.
  • In January I had plastic sealant sprayed onto a molar that was in danger of getting a cavity, at a dentist's office in Stowe, Vermont. The sealant was fixed by UV light.


    I thought that was plastic, which if true would make the post summary ("the first..") false.

  • ... 'this' has been reported by the swedish magazine 'Illustrerrad Vetenskap, NR 15/2002, page 29'

    BTW, for those of you who want to know the name of the 'chemical molecule' it's, Azobenzen [google.com].

  • Oh boy! so this kind of plastic going to provide skins for terminator-II or terminator-III ?

  • melting!

    :-)

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