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Science News Technology

New Shape-Shifting Polymer Holds 1,000 Times Its Own Mass - Watch Out Plastic Man! (techtimes.com) 57

University of Rochester researchers have announced the development of a new polymer, capable of supporting 1,000 times its own mass. Polymers that can change shape when heated have been developed in the past, yet this new polymer exhibits the rare quality of becoming flexible when exposed to body heat. This property, which can be used to change the shape of a device, could make the substance useful in medical applications. When the new polymer is removed from the heat source (such as human body), the material immediately returns to its original configuration.
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New Shape-Shifting Polymer Holds 1,000 Times Its Own Mass - Watch Out Plastic Man!

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  • by tlambert ( 566799 ) on Sunday February 14, 2016 @02:25PM (#51506745)

    Medical applications?

    "How did the poor bastard die?"

    "He was out skiing, and his artificial kidney reverted to its original shape, a spiky brick."

  • by Anonymous Coward on Sunday February 14, 2016 @02:43PM (#51506827)

    Fleshlight :)

  • by Irate Engineer ( 2814313 ) on Sunday February 14, 2016 @02:49PM (#51506849)

    What the fuck does that mean?

    1 sq. inch (sectional area) of cheap steel can support 36,000 lbs in tension without yielding.

    A 1 inch cube of steel weighs 0.29 lbs and can support 36,000 lbs, so that's 124,000 times!

    This raises a red flag that whoever wrote this doesn't really get mechanics.

    • by wonkey_monkey ( 2592601 ) on Sunday February 14, 2016 @03:01PM (#51506913) Homepage

      I'm pretty sure a supermarket plastic bag could hold nearly 1000x its own mass - certainly within an order of magnitude, at the very least. And those are made out of a polymer too!

      They even shape-shift, crinkling up into a little blob if you set them on fire. They won't shape shift back again, admittedly...

      • I'd go out on a limb and take a bet that a modern plastic grocery bag can hold 5,000x its weight... they hold (on the order of) 10lbs, so 1/500 lb - how many grams do you think a single bag weighs (without the printer's ink on it)? If it's less than 1 gram per bag, we've got 5000:1 performance there.

        • The polymer used to make those bags has a curious property of weakening sharply when in proximity to a garden path.

      • Per square inch? Typically these forces are measured over a specific area otherwise, with sufficient material I could make any statement hold true - wet paper will hold thousands of pounds too if you spread the material out enough.

        • Per square inch?

          Does it make sense to ask that in this context? The headline says "1000 times its own mass".

          A one inch square will hold 1000 times its own mass. A two inch square will hold 4x as much as the previous square, but it's still 1000 times its own mass.

          wet paper will hold thousands of pounds too if you spread the material out enough.

          One pound of wet paper won't hold a thousand pounds of something.

          Although technically the article doesn't specify under what strength gravity this material can operate...

    • From deep within the article:

      Tuning the trigger temperature is only one part of the story. We also engineered these materials to store large amount[s] of elastic energy, enabling them to perform more mechanical work during their shape recovery,

      The capability to lift 1,000 times its own mass means that a device constructed from 1/28th ounce (about the weight of a typical paper clip), could lift a one-liter bottle of water.

      Even the article uses "support" many times, which does relate to stress (measured in N or lbs in the US). However, the scientists involved were talking about lifting, i.e. mechanical work, which is measured in N.m (or lbs.ft for Americans). So there is another dimension that you need to multiply in and you will find that the units do in fact match up. Since this distance is not specified in the article, it's still quantitatively meaningless, since for example an enormous pneumat

      • This makes some sense, but yes, the physical property is so buried as to be meaningless and impossible to judge the value of the material.

        The link to the school page has the same text, so I expect that this was written by campus public relations who completely mangled the technical details. I suppose the researchers slapped their foreheads repeatedly while reading this.

    • FTFY: whoever wrote this doesn't really get metrics

      (As a side note: steel is good at tension, it is a safe bet the force the polymere is mentioned to "support" is pressure)

    • What the fuck does that mean?

      1 sq. inch (sectional area) of cheap steel can support 36,000 lbs in tension without yielding.

      A 1 inch cube of steel weighs 0.29 lbs and can support 36,000 lbs, so that's 124,000 times!

      This raises a red flag that whoever wrote this doesn't really get mechanics.

      Interesting topic.

      Canada would vote Sanders in with a landslide majority. Republicans want Donald Duckish. Managing a TV show is not like managing a country. You can't delegate away responsibility.

  • by Mostly a lurker ( 634878 ) on Sunday February 14, 2016 @02:54PM (#51506877)

    I did RTFA, but am still confused. It seems a major advantage is that the polymer returns to its original shape when heat is removed, but just normal body heat allows it to be molded into other shapes. In a medical setting, how does it return to the original shape given that it is presumably installed in an environment with a temperature at or near body heat? Also, body heat is not that hot. In non medical applications, what is a range of temperatures where it will retain its strength and resist going out of shape?

    • by Lorens ( 597774 )

      Yes, would like examples of medical uses. It seems like it would be more useful to have things become malleable at lower temperatures (there are already lots that become malleable at higher ones). Gonna have to RTFA I suppose.

      • Thank OzPeter below for the real link. Body heat causes the material to revert to original shape, apparently exerting considerable force to do so. I'm sure there are lots of surgical applications.

        • Stents come to mind. It might be more biocompatible than the existing materials used.

          Blood is a very awkward substance - it tends to clot on contact with practically anything that isn't a blood vessel.

    • I did RTFA, but am still confused. It seems a major advantage is that the polymer returns to its original shape when heat is removed, but just normal body heat allows it to be molded into other shapes. In a medical setting, how does it return to the original shape given that it is presumably installed in an environment with a temperature at or near body heat? Also, body heat is not that hot. In non medical applications, what is a range of temperatures where it will retain its strength and resist going out of shape?

      Simple, you just freeze the patient.

  • The real link (Score:5, Informative)

    by OzPeter ( 195038 ) on Sunday February 14, 2016 @02:57PM (#51506891)

    University of Rochester Body heat triggers shape change in new type of polymer [rochester.edu]

    The real source even has video

    • by ed.mps ( 1015669 )
      Thank you, sir, linking to the source seems to be forgotten in the 00's
    • by Kohath ( 38547 )

      So this article says the opposite of the summary: the material reverts to it's original shape when body heat is applied. That sounds more useful for medical applications.

      The summary speaks of a material that loses it's original shape as body heat is applied (and presumably regains it once it cools down). That sounds less useful.

  • Watch out: Plastic man!
  • The summary has it back to front. The polymer can be stretched into other shapes which it keeps until it is raised to body temperature. The material will snap back into shape even when lifting a weight or crush an object that it has been wound around.

    This means that in surgery a strand of polymer can be stretched to put into place, whereupon it springs back into the desired shape, perhaps constricting something, or raising / pulling something.

    • Would make fantastic replacement bones then. You could form a bone then make it malleable so it can be inserted via key hole or around something else you don't want to move and then have it move back to the original correct shape.

      How you keep it in the malleable temp range during this process though may be the hardest part.

  • by Anonymous Coward

    Canadian electronic musician and DJ Richie Hawtin, also known as Plastikman, is wondering why everyone is telling him to "look out".
    https://en.wikipedia.org/wiki/Richie_Hawtin

  • What the fuck is the point of that in the headline? Are we just shouting random words that have some vague connection to the article now?
  • fits the story: 'Force needed to accelerate 2.2lbs of cookies = 1 Fig-newton to 1 meter per second'

As you will see, I told them, in no uncertain terms, to see Figure one. -- Dave "First Strike" Pare

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