Featured Research

from universities, journals, and other organizations

'Retrospective Rubber' Remembers Its Old Identities

Date:
December 16, 2007
Source:
University of Rochester
Summary:
Researchers 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 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.

Mitchell Anthamatten explores the properties of the new rubbery material. Unlike conventional shape-memory polymers 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.
Credit: Image courtesy of University of Rochester

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.

Related Articles


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."


Story Source:

The above story is based on materials provided by University of Rochester. Note: Materials may be edited for content and length.


Cite This Page:

University of Rochester. "'Retrospective Rubber' Remembers Its Old Identities." ScienceDaily. ScienceDaily, 16 December 2007. <www.sciencedaily.com/releases/2007/12/071212201154.htm>.
University of Rochester. (2007, December 16). 'Retrospective Rubber' Remembers Its Old Identities. ScienceDaily. Retrieved March 5, 2015 from www.sciencedaily.com/releases/2007/12/071212201154.htm
University of Rochester. "'Retrospective Rubber' Remembers Its Old Identities." ScienceDaily. www.sciencedaily.com/releases/2007/12/071212201154.htm (accessed March 5, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Thursday, March 5, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Gas Production Cut on Earthquake Fears

Gas Production Cut on Earthquake Fears

Reuters - Business Video Online (Mar. 5, 2015) The Dutch government has cut production at Europe&apos;s largest gas field in Groningen amid concerns over earthquakes which are damaging local churches. As Amy Pollock reports the decision - largely politically-motivated - could have big economic conseqeunces. Video provided by Reuters
Powered by NewsLook.com
Star Wars-Inspired Prototype Creates Holographic Display

Star Wars-Inspired Prototype Creates Holographic Display

Reuters - Innovations Video Online (Mar. 5, 2015) A prototype holographic display named Leia - after the Star Wars princess who appeared in holographic form asking Obi-Wan Kenobu for help - is demonstrated at the Mobile World Congress in Barcelona. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
IKEA and Samsung Launch Embedded Wireless Charging Range

IKEA and Samsung Launch Embedded Wireless Charging Range

Reuters - Innovations Video Online (Mar. 5, 2015) Samsung and IKEA hope their new embedded wireless charging products, launched at Barcelona&apos;s Mobile World Congress, will tempt consumers eager for plugless power. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
Samsung Unveils $30,000 'Dream Doghouse'

Samsung Unveils $30,000 'Dream Doghouse'

Buzz60 (Mar. 5, 2015) On display at the Crufts dog show in England, the &apos;dog kennel of the future&apos; comes with features like a doggie treadmill and Samsung tablet. Mike Janela (@mikejanela) has more. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins