Featured Research

from universities, journals, and other organizations

Simple Polymer Moves With Electricity

Date:
July 1, 1998
Source:
Penn State
Summary:
A material originally developed for clear plastic bags may some day be used for artificial muscles, skin and organs that move like the real thing, according to a team of Penn State materials scientists.

UNIVERSITY PARK, Penn.--A material originally developed for clear plastic bags may some day be used for artificial muscles, skin and organs that move like the real thing, according to a team of Penn State materials scientists.

"This polymer is not new, but we can now alter it so it moves much more when an electric field is applied," says Dr. Qi-Ming Zhang, associate professor of electrical engineering and an associate at Penn State's Materials Research Laboratory. "The larger motion is an order of magnitude improvement in performance in acoustics, biomedical instrumentation and artificial organs possible."

Poly(vinylidene fluoride-trifluoroethylene) Copolymer was developed for sturdy, thin-film bags to store blood and other liquids. Researchers have long known that it has weak piezoelectric characteristics. When an electric voltage was placed on the film, the film moved, slightly. When pressure deformed the film, it produced electricity.

"As a piezoelectric material, this polymer was not very promising, the response was very small," says Zhang. "But as an electrostrictive material, the response is much larger and we can actually see it move under a voltage."

Electrostrictive materials are similar to piezoelectric materials, but are not polarized.

Zhang, working with Vivek Bharti and Xin Zhong Zhao, Penn State Postdoctoral Fellows, found a way to alter the polymer and create a material that moved 40 times more than some of the best known materials and is much easier and less expensive to manufacture.

Reporting in today's (June 26) issue of Science, the researchers explained how bombarding the material with electrons altered both the molecular conformation of the material and created new chemical bonds. We insert defects into the material and it becomes more compliant and flexible and has a higher dielectric constant, says Zhang.

Polymer materials consist of long chains that usually look like strands of spaghetti tangled around each other. The electron bombardment causes crosslinks to form between nearby strands and changes the molecular conformation. The altered material has a deformation rate under a high electric field of 4 percent or a 4-inch change for every 100 inches.

"This material is very sturdy, biologically neutral, can be molded in many shapes, is flexible and pliable," says Zhang. "Most electrostrictive materials are brittle ceramics that cannot move very far without breaking. Other known polymers can exhibit similar behavior, but they are very soft."

The flexibility, pliable and ease of manufacture of Poly(vinylidene fluoride-trifluoroethylene) Copolymer make it ideal for improved acoustic transducers for use in medical imaging equipment, underwater detectors and stereo speakers. Because of its high dielectric constant, the material could also be used for capacitors. In the long term, applications as artificial skin that senses touch, drug delivery systems, artificial muscles and organs may all be possible.

While easy to manufacture, pretreatment of the material does makes a difference. The initial material needed to be purer than that used to manufacture thin-film bags. The treatment temperature, annealing, quenching and whether or not the material was stretched also influenced the outcome.

"Eventually, we should be able to fine tune the properties over a large range of values to tailor the material to specific applications," says Zhang.

The researchers would also like to try working with strands or wires of the polymer in addition to thin films.


Story Source:

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


Cite This Page:

Penn State. "Simple Polymer Moves With Electricity." ScienceDaily. ScienceDaily, 1 July 1998. <www.sciencedaily.com/releases/1998/07/980701082033.htm>.
Penn State. (1998, July 1). Simple Polymer Moves With Electricity. ScienceDaily. Retrieved September 23, 2014 from www.sciencedaily.com/releases/1998/07/980701082033.htm
Penn State. "Simple Polymer Moves With Electricity." ScienceDaily. www.sciencedaily.com/releases/1998/07/980701082033.htm (accessed September 23, 2014).

Share This



More Matter & Energy News

Tuesday, September 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Will Living Glue Be A Thing?

Will Living Glue Be A Thing?

Newsy (Sep. 23, 2014) Using proteins derived from mussels, engineers at MIT have made a supersticky underwater adhesive. They're now looking to make "living glue." Video provided by Newsy
Powered by NewsLook.com
Company Copies Keys From Photos

Company Copies Keys From Photos

Newsy (Sep. 22, 2014) A new company allows customers to make copies of keys by simply uploading a couple of photos. But could it also be great for thieves? Video provided by Newsy
Powered by NewsLook.com
The Hyped-Up Big Bang Discovery Has A Dust Problem

The Hyped-Up Big Bang Discovery Has A Dust Problem

Newsy (Sep. 22, 2014) An analysis of new satellite data casts serious doubt on a previous study about the Big Bang that was once hailed as revolutionary. Video provided by Newsy
Powered by NewsLook.com
Rockefeller Oil Heirs Switching To Clean Energy

Rockefeller Oil Heirs Switching To Clean Energy

Newsy (Sep. 22, 2014) The Rockefellers — heirs to an oil fortune that made the family name a symbol of American wealth — are switching from fossil fuels to clean energy. Video provided by Newsy
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