Featured Research

from universities, journals, and other organizations

Applied Scientists Create Wrinkled 'Skin' On Polymers

Date:
January 18, 2007
Source:
Harvard University
Summary:
Applied scientists demonstrated a new method for developing wrinkled hard skins on the surface areas of polymers using a focused ion beam. The technique has potential use for biological sensors and microfluidic devices and may offer new ways to build custom-made cell templates for tissue engineering.

Wrinkled hard skin on polymer surface induced by focused ion beam. The wrinkles are hierarchical with the primary wavelength of 465 nm.
Credit: Photo graph courtesy of Moon et al.

Applied scientists demonstrated a new method for developing wrinkled hard skins on the surface areas of polymers using a focused ion beam. By controlling the direction and intensity of the ion beam, the researchers literally sculpted patterns on flat areas of polydimethylsiloxane, a silicon-based organic polymer (more commonly known as the primary ingredient in Silly Putty). The technique has potential use for biological sensors and microfluidic devices and may offer new ways to build custom-made cell templates for tissue engineering.

The work is a collaboration among researchers at Harvard University and Seoul National University. The Harvard group consisted of John W. Hutchinson, Abbott and James Lawrence Professor of Engineering, Myoung-Woon Moon, Post-doctoral Fellow, and Ashkan Vaziri, Lecturer on Engineering and Research Associate in Applied Mechanics, all of Harvard Engineering and Applied Sciences. Their findings were published in the Proceedings of the National Academy of Sciences. The researchers have also filed for a U.S. patent covering the discovery.

"This technique is a one-step process for creating wrinkled skins," explains Vaziri. "The method is more robust compared with traditional techniques. The patterns can be generated along desired paths by simply controlling the relative movement of the ion beam and polymeric substrate. It's almost like using an airbrush on fabric. At a smaller scale the desired morphology of wrinkles can be achieved by controlling the ion beam intensity."

Because only the areas exposed to the beam are affected, the method enabled the scientists to create a variety of patterns--from simple one-dimensional wrinkles to peculiar and complex hierarchical nested wrinkles--along desired paths. Specific examples to date include "S" shapes, circular patterns, and long horizontal channels akin to the repeating tines of a closed zipper.

"Irradiation by the ion beam alters the chemical composition of the polymer close to its surface and forms a thin stiff skin which wants to expand," explains Vaziri. "The consequent mismatch between the mechanical strain of the generated stiff skin and the underlying polymeric substrate, almost like a tug-of-war, buckles the skin and forms the wrinkle patterns."

Such patterns can be used in the construction of microfluidic devices for particle separation and mixture and also have potential use in designing biosenors. The researchers have also started a close collaboration with scientists at the Harvard-MIT Division of Health Sciences and Technology aimed at exploring the behavior of living cells on these patterned substrates. Such research may lead to the development of an effective and robust method to build custom templates for engineering and growing tissues.

"We are approaching this field of research from various directions," says Vaziri. "At the moment we are looking at the effect of ion beam energy and have been able to reduce the wavelength of the wrinkles to 50 nanometers. Manipulation at such a small scale makes this method even more attractive. We are also building multifunctional microfluidic devices for the mixing of flow at very small scales and stretching of proteins and DNA. These new efforts, while at early stages of development, are very promising."

Vaziri, Moon and Hutchinson's co-authors are Sang Hoon Lee, Jeong-Yun Sun, and Kyu Hwan Oh, all from the School of Materials Science and Engineering at Seoul National University. The research was supported in part by the Korea Research Foundation, the Center for Advanced Materials Processing of the 21st Century Frontier R&D Program, the Office of Naval Research, and Harvard Engineering and Applied Sciences.


Story Source:

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


Cite This Page:

Harvard University. "Applied Scientists Create Wrinkled 'Skin' On Polymers." ScienceDaily. ScienceDaily, 18 January 2007. <www.sciencedaily.com/releases/2007/01/070116204944.htm>.
Harvard University. (2007, January 18). Applied Scientists Create Wrinkled 'Skin' On Polymers. ScienceDaily. Retrieved September 21, 2014 from www.sciencedaily.com/releases/2007/01/070116204944.htm
Harvard University. "Applied Scientists Create Wrinkled 'Skin' On Polymers." ScienceDaily. www.sciencedaily.com/releases/2007/01/070116204944.htm (accessed September 21, 2014).

Share This



More Matter & Energy News

Sunday, September 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

What This MIT Sensor Could Mean For The Future Of Robotics

What This MIT Sensor Could Mean For The Future Of Robotics

Newsy (Sep. 20, 2014) MIT researchers developed a light-based sensor that gives robots 100 times the sensitivity of a human finger, allowing for "unprecedented dexterity." Video provided by Newsy
Powered by NewsLook.com
MIT BioSuit A New Take On Traditional Spacesuits

MIT BioSuit A New Take On Traditional Spacesuits

Newsy (Sep. 19, 2014) The MIT BioSuit could be an alternative to big, bulky traditional spacesuits, but the concept needs some work. Video provided by Newsy
Powered by NewsLook.com
New Music With Recycled Instruments at Colombia Fest

New Music With Recycled Instruments at Colombia Fest

AFP (Sep. 19, 2014) Jars, bottles, caps and even a pizza box, recovered from the trash, were the elements used by four musical groups at the "RSFEST2014 Sonorities Recycling Festival", in Colombian city of Cali. Duration: 00:49 Video provided by AFP
Powered by NewsLook.com
Virtual Reality Headsets Unveiled at Tokyo Game Show

Virtual Reality Headsets Unveiled at Tokyo Game Show

AFP (Sep. 18, 2014) Several companies unveiled virtual reality headsets at the Tokyo Game Show, Asia's largest digital entertainment exhibition. Duration: 00:48 Video provided by AFP
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:
from the past week

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