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Mitch Anthamatten Explains a Shape-Memory Cycle Involving Strain Induced Crystallization


Hi. My name is Mitch Anthamatten and I’m with the Department of Chemical Engineering at the University of Rochester. I’m going
tell you about a very interesting material that my research group has
developed. Here is a sample of a polymer elastomer that is called a shape memory
polymer and we’ve made this material that you can simply stretch. So you
apply force to it so the network chains have been deformed and bringing them
closer to their crystalline state. So simply by applying a force, the
material crystallizes and the crystallization causes the material to
stabilize the shape, this deformed shape. So I can actually let go of the sample and
you can see that it’s been stabilized in the stretch state and what’s unique
about this material is even contacting the body is enough to melt those
crystals causing it to retract to its original shape and I’m just pressing my
finger against the material and it’s recovering to its original shape and
it’s also releasing all of that stored elastic energy that was in the samples.
So here we have it. The material has fully recovered. We’re really excited about applications
that can come from such properties. We’re particularly interested in
biomedical applications, where the recovery temperature needs to be near
the human body temperature and at the same time the shape memory polymer has to exert a lot of forces during the recovery process releasing a lot of the
stored energy. A production of the University of
Rochester. Please visit us online and subscribe to our channel for more videos.

Glenn Chapman

9 Comments

  1. With smart materials many things become possible. Very interesting . There are a lot of interesting applications.

  2. Fabulous. My imagination is running hard over the implications of this material. 🙂

  3. Hi Mitch,
    What about using the polymer as a temperature controlled motor. Use your expanding and contracting forms of polymer with a temperature change
    To cause a difference in length. Which could drive an alternator to spin & create power.
    If you used spokes to alternately shade & expose the materials to the sun, would it continually cool & heat (shrink & expand) enough to drive a motor ?
    Large scale may lead to a fairly reliable source of energy.
    Jim T

  4. As someone who's got a love for mechanical augmentation and prosthetic limbs, I've got to ask, would it be possible to impregnate the polymer with a conductive metal to create a quasi semi conductive plastic, so you could control it with very light levels of voltage, sort of creating a muscle like structure? I'm thinking of something along the lines of aluminide.

    As I understand, you can control the temperature of which the polymer returns to it's original shape so with thicker strands of the impregnated polymer woven together would strikingly act like protein, if you were to seal off individual bundles allowing you to selectively apply low currents for fine motor control. Even without, it could be possible to weave thin filaments of conductive metal to pass the current and control the temperature of the polymer.

    I guess by also going by a muscle based design, you could possibly not have to worry about the method of control, like if you were designing a hand, well a hand needs to open and close, when you open your hand, the potential elastic energy is stored in the inverse portion of muscles not pulling it open. (Sorry, biology is far from my strong suit)

    I guess this also raises the question of, what kind of speeds would you be able to achieve with this sort of polymer? Would having multiple strands working in conjunction prove to create a far faster return to form speed?

  5. Mitch,
    I'd very much like to get in contact with you. I have an application that actually has a demand for shape memory material; and I'm trying to select the best one. Currently I'm using NiTi, but I figured that polymers deserve a shot.

    Is there any way I can talk to you or an expert in the field while having my IP protected?

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