Shapeshifting is no longer science fiction
Making things change to the shape you want : a video briefing on Shape Memory Materials
This video (it’s certainly not new, but it’s an excellent introduction to the basics of the subject) has a point where a straight strip of plastic spookily manages to coil itself around a rod, and then you watch it un-spiral itself back to its original shape.
This capability may have many seriously important medical applications, but as a visual experience, this extraordinary demonstration will permanently shape the way you will remember and visualise this intriguing new technology.
‘Retrospective Rubber‘ Remembers Its Old Identities
Researchers at the University of Rochester have developed a shape-memory rubber that may enable applications as diverse as biomedical implants, conformal face-masks, self-sealing sutures, and “smart” labels.
The material, described in the journal Advanced Materials, forms a new class of shape-memory polymers, which are materials that can be stretched to a new shape and will stay in that form until heated, at which time they revert to their initial shape.
Unlike conventional shape-memory polymers, however, the new material is transparent, rubbery, and most importantly, engineers will be able to control the speed at which it returns to its original shape. Other shape memory polymers use crystallization to hold a temporary shape, which often makes them opaque, hard, and brittle in their frozen states, and this can limit their use.
“At higher temperatures the material stretches like a rubber band, but, at lower temperatures, it stiffens up,” says Mitchell Anthamatten, assistant professor of chemical engineering and inventor of the material.
“This property can be used to temporarily hold the material in a deformed shape; and its original shape can be recalled by heating.
Imagine an optical lens that can be triggered to change shape, a face-mask that can fit any user, or a biomedical implant that changes shape slow enough for a surgical procedure.”
The new rubber functions differently than conventional shape-memory materials by using “sticker groups”—hydrogen bonding groups that form temporary bonds.
These sticker groups break and reform constantly. It’s akin to tearing a net apart only to find that new knots have formed between different strands.
When the material is stretched, new bonds form that hold the material, temporarily, in its deformed shape. Creating the rubber with different amounts of sticker groups controls the rate at which the rubber returns to its original shape.
With this control, Anthamatten envisions applications that today’s shape-memory polymers simply can’t fulfill.
“The pressure at which you hold together a sutured wound determines a lot about how it will heal,” says Anthamatten.
“This polymer could be made into a thread that responds precisely to body temperature, tightening the sutures to the perfect pressure.”
Anthamatten is currently investigating how dyes diffuse through his networks. “We expect the rate of dye diffusion to increase with temperatures,” says Anthamatten.
This property may enable “smart” labels that account for time and temperature and can inform customers when products are about to expire.
“We may not always have to rely on the expiration date. What if our milk was not refrigerated properly? What if the air conditioner failed for some time at the pharmacy? People want to know that their products are fresh.”
One aspect of the clear rubber that surprised Anthamatten was how easy it is to make. “It’s ridiculously simple,” he says, “and we’re fascinated by how small modifications lead to major changes in how the material behaves.”
Contact: Jonathan Sherwood Jonathan.sherwood@rochester.edu 585.273.4726
About the University of Rochester
The University of Rochester (www.rochester.edu) is one of the nation’s leading private universities. Located in Rochester, N.Y., the University gives students exceptional opportunities for interdisciplinary study and close collaboration with faculty through its unique cluster-based curriculum.
Its College, School of Arts and Sciences, and Hajim School of Engineering and Applied Sciences are complemented by its Eastman School of Music, Simon School of Business, Warner School of Education, Laboratory for Laser Energetics, Schools of Medicine and Dentistry and Nursing, and the Memorial Art Gallery.
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“This property may enable “smart” labels that account for time and temperature and can inform customers when products are about to expire.
“We may not always have to rely on the expiration date. What if our milk was not refrigerated properly? What if the air conditioner failed for some time at the pharmacy? People want to know that their products are fresh.”
This part really got my attention. Such a great idea for the use of new shape-memory rubber, had to dig deeper on that. Found some information from Mitchell Anthamatten:
http://allaboutplastics.wordpress.com/2008/02/20/shape-memory-rubber/
“He said the new polymers might be used in “smart” labels—labels that can change color or coding to indicate, for example, the age or temperature history of food products or prescription medications. In this possible application, shape-memory rubber could function as a “gate,” enabling dye molecules to diffuse on the label—or halting them—depending on a product’s age or the temperature at which it has been kept.”
This really sounds promising. Customers are given the possibility not only to control ‘use by date’, but what is more important, how products were stored so far. This would absolutely revolutionize the market as we know it. Wonder how would producers react to this idea? And what about shippers and others in supply chain?
@GregP’s comment:
“This really sounds promising. Customers are given the possibility not only to control ‘use by date’, but what is more important, how products were stored so far. This would absolutely revolutionize the market as we know it. Wonder how would producers react to this idea? And what about shippers and others in supply chain?”
The innovation has actually started quite a buzz when it was released, and the reaction is very positive, with different research grants made in harnessing the shape memory polymers’ potential. This recent article shows the results of the positive reaction to SMPs:
http://www.massdevice.com/shape-memory-polymers-replace-nitinol
“Avant has been exploring this area of innovation representing a next generation of devices that not only can perform to exacting standards that doctors and surgeons demand, but will also allow new applications and uses for existing device designs. It also may allow device use in environments where the material properties of nitinol prove a disadvantage or preclude its use.”
The SMP’s use in the field of medical science has really shown promise, as this article proves. But the question now is how to expand on the SMP’s practicability once it enters the consumer market; will SMP’s unique properties provide more help or sow confusion among us, the ordinary consumers?
That’s a good point there Rob, was wondering on that as well. Some people, especially elders, might find it difficult to get used to this new use of SMPs in everyday life. However, I see it as a way to go for market, especially consumables.
I imagine it would bring new quality to production and storing processes in product’s life cycle, as those would be controlled even more rigorously.
Have you heard Rob – or anyone else for that matter – if any company around the world started to introduce SMPs in consumable goods, manufactured for casual, everyday market? Or is it still to soon? Maybe any plans to do so?
I’ve done a bit of research on the subject Greg, and so far, all these have remained a potential with no tangible or concrete products to speak of that use SMPs for, say, expiration date and life storage. Here’s another example where SMPs are being developed:
http://www.orthodonticproductsonline.com/news/2010-03-30_01.asp
The article briefly introduces the development of SMPs for orthodontic braces. This is one product that I think will surely benefit from the potential use of SMPs. But for now, since this and most of the products that utilize SMPs remain a promise, consumers can only hope that SMPs will not be a burden to them, especially to their pockets.
Surely, medical use will come first for SMPs, as they offer such vast possibilities to surgeons and other practitioners. Just like on the pictures from this article:
http://www.azom.com/details.asp?ArticleID=1542
It’s amazing, how this fibres from biodegradable (!) shape memory polymers change their shape in 20 seconds – check pictures there, it is really cool.
I hope that use of SMPs in everyday products won’t make prices go up, consumers would be fuming if they would have to pay for something that they are not demanding and can perfectly live without, like they do now.
You’re quite right there Greg. If these polymers prove to be expensive for the common consumers, I don’t think that developing them for everyday use would be beneficial at all. Probably best have these SMPs remain as instruments for manufacturing and repair, much like this SMP-based product, Veritex.
http://www.crg-industries.com/datasheets/veritex%20data%20sheet.pdf
But I am still optimistic that scientists would be able to develop the SMPs for inexpensive use (better if for free) that consumers can utilize with maximum usability.
I’m also pretty sure that SMPs would become cheaper over time. Also, one of the sentences from original article that started our comments gives hope it would be so:
“One aspect of the clear rubber that surprised Anthamatten was how easy it is to make. “It’s ridiculously simple,” he says, “and we’re fascinated by how small modifications lead to major changes in how the material behaves.”
Simple = cheap in most of the cases, so there is hope it will end like that for future consumers. Let’s hope we would use it one day in our lives Rob. How about plastic bottles, changing their shapes in your fridge, whenever your orange juice has the perfect temperature for consumption? Heh, yes please