Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Body temperature triggers newly developed polymer to change shape

09.02.2016

Material can lift 1,000 times its mass

Polymers that visibly change shape when exposed to temperature changes are nothing new. But a research team led by Chemical Engineering Professor Mitch Anthamatten at the University of Rochester created a material that undergoes a shape change that can be triggered by body heat alone, opening the door for new medical and other applications.


A time-lapse photo of a new shape-memory polymer reverting to its original shape after being exposed to body temperature.

Photo by Adam Fenster/University of Rochester

The material developed by Anthamatten and graduate student Yuan Meng is a type of shape-memory polymer, which can be programmed to retain a temporary shape until it is triggered--typically by heat--to return to its original shape.

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

The findings are being published this week in the Journal of Polymer Science Part B: Polymer Physics.

The key to developing the new polymer was figuring out how to control crystallization that occurs when the material is cooled or stretched. As the material is deformed, polymer chains are locally stretched, and small segments of the polymer align in the same direction in small areas--or domains--called crystallites, which fix the material into a temporarily deformed shape. As the number of crystallites grows, the polymer shape becomes more and more stable, making it increasingly difficult for the material to revert back to its initial--or "permanent"--shape.

The ability to tune the trigger temperature was achieved by including molecular linkers to connect the individual polymer strands. Anthamatten's group discovered that linkers inhibit--but don't stop--crystallization when the material is stretched. By altering the number and types of linkers used, as well as how they're distributed throughout the polymer network, the Rochester researchers were able to adjust the material's stability and precisely set the melting point at which the shape change is triggered.

Heating the new polymer to temperatures near 35 ?C, just below the body temperature, causes the crystallites to break apart and the material to revert to its permanent shape.

"Our shape-memory polymer is like a rubber band that can lock itself into a new shape when stretched," said Anthamatten. "But a simple touch causes it to recoil back to its original shape."

Having a polymer with a precisely tunable trigger temperature was only one objective. Of equal importance, Anthamatten and his team wanted the material to be able to deliver a great deal of mechanical work as the shape transforms back to its permanent shape. Consequently, they set out to optimize their polymer networks to store as much elastic energy as possible.

"Nearly all applications of shape memory polymers will require that the material pushes or pulls on its surroundings," said Anthamatten. "However, researchers seldom measure the amount of mechanical work that shape-memory polymers are actually performing."

Anthamatten's shape-memory polymer is capable of lifting an object one-thousand times its weight. For example, a polymer the size of a shoelace--which weighs about a gram--could lift a liter of soda.

Anthamatten says the shape-memory polymer could have a variety of applications, including sutures, artificial skin, body-heat assisted medical dispensers, and self-fitting apparel.

Media Contact

Peter Iglinski
peter.iglinski@rochester.edu
585-273-4726

 @UofR

http://www.rochester.edu 

Peter Iglinski | EurekAlert!

More articles from Materials Sciences:

nachricht Decoding cement's shape promises greener concrete
08.12.2016 | Rice University

nachricht Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D
08.12.2016 | DOE/Brookhaven National Laboratory

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>