PaintSquare.com
      | Connect Follow us on Twitter Like us on Facebook
About | Subscribe | Advertise
  

 

Paint and Coatings Industry News

Main News Page


UV Heals New Polymer Repeatedly

Friday, January 21, 2011

Comment | More

U.S. and Japanese scientists have developed a polymer that can heal itself over and over again when irradiated with UV light.

This is the first material in which capped covalent bonds reattach repeatedly, even allowing fully separated pieces to be fused back together, the team reports in Angewandte Chemie, the peer-reviewed journal of the German Chemical Society.

In "Repeatable Photoinduced Self-Healing of Covalently Cross-Linked Polymers through Reshuffling of Trithiocarbonate Units", the research team explains how the new polymeric material repairs itself repeatedly.

shredded polymer samples

The technology could have significant implications for protective coatings and other functional materials subject to damage and weathering.

Restructuring Under UV Light

Previous materials have been able to repair themselves once. Typically, these contain tiny capsules that tear open to release a chemical agent when the material is damaged, explains journal publisher Wiley. Other materials “can repair themselves repeatedly but lack the covalent bonds that increase materials strength and stability.”

The new polymer, however, is cross-linked through trithiocarbonate units, Wiley explains. These carbon atoms are bonded to three sulfur atoms, two of which use their second bonding position to attach to another carbon atom.

“These groups have a special property: They can restructure under UV light,” according to Wiley. “The light breaks one carbon–sulfur bond in the trithiocarbonate groups. This produces two radicals—molecules with a free, unpaired electron.

“The radicals are very reactive and attack other trithiocarbonate groups to form new carbon–sulfur bonds while breaking others to form more free radicals. The chain reaction stops when two radicals react with each other.”

Healing Cut Fragments

The material was developed by Krzysztof Matyjaszewski and colleagues at Carnegie Mellon University in Pittsburgh, PA, and Kyushu University in Japan.

“The researchers were able to heal cut polymer fragments with irradiation—either immersed in liquid or in bulk,” the journal reported. “They only had to firmly press the cut edges together and irradiate them” to cause the edges to grow back together.

Even shredded polymer samples could simply be pressed together and irradiated to be fused into a continuous piece, the publisher said.

“The resulting object was in the shape of the cylindrical tube in which the procedure was carried out. This self-healing process can be carried out repeatedly on the same sample. The material is thus also interesting as a new recyclable product.”

   

Tagged categories: Polymers; Research

Comment Join the Conversation:

Sign in to our community to add your comments.

Axxiom Manufacturing
The Undisputed
Industry Leader.

Proven Innovation. Job Performance. Industry Training. Workplace Safety. Only Schmidt® abrasive blast equipment by Axxiom Manufacturing delivers it all!


Modern Safety Techniques
Modern Safety Techniques

With our unique LTCat, we can help to provide clean, safe breathing air to your workers. Take a look at our Breathing Air Systems, we supply at least twice as much charcoal as our competitors! Modern


KTA-Tator, Inc. - Corporate Office
KTA Analyzes
Coating Failures

• Field Diagnosis
• Lab Diagnosis
• Determination of Cause
• Recommendations
www.kta.com
800-245-6379


SAFE Systems, Inc.
Portable Dust Collectors for Tough Environments

Trailer and skid-mounted models in numerous sizes, powered by electric and/or diesel. Sloped roofs, multiple dust inlets, high static, dampered fans. Lockable power & drive compartments.


Atlantic Design, Inc.
GOING PLACES YOU ONLY DREAM ABOUT!

We custom design.
We sell new & used.
We upgrade.
We retrofit.
We rent.
What are your equipment needs?
Cleverly simple. Clearly ADI. 866.Call.ADI


HoldTight Solutions Inc.
NO FLASH RUST -
NO CONTAMINANTS

Our HoldTight®102 salt remover & flash rush inhibitor prevents flash rust by removing surface contaminants.
Contact us for your nearest distributor. (800) 319.8802 sales@holdtight.com


CS Unitec
Surface Prep & Material Removal

CS Unitec’s Floor Planers remove coatings & corrosion from concrete & metal surfaces. Produce keyed profiles for waterproofing applications. info@csunitec.com


Absolute Equipment/Grand Rental Station
Portable Power from Absolute Equipment

•Compressors
•Lighting Systems
•Generators
•Light Compaction
Sales • Rental • Service
Call 1-866-931-6655
Over a century of
providing excellence.

 
 
 
Technology Publishing

The Technology Publishing Network

The Journal of Protective Coatings & Linings (JPCL) PaintSquare
Durability + Design Paint BidTracker

 
EXPLORE:      JPCL   |   PaintSquare News   |   Interact   |   Buying Guides   |   Webinars   |   Resources   |   Classifieds
REGISTER AND SUBSCRIBE:      Free PaintSquare Registration   |   Subscribe to JPCL   |   Subscribe to PaintSquare News
MORE:      About PaintSquare.com   |   Privacy policy   |   Terms & conditions   |   Site Map   |   Search   |   Contact Us
 

© Copyright 2000-2015, Technology Publishing / PaintSquare, All rights reserved
2100 Wharton Street, Suite 310, Pittsburgh PA 15203-1951; Tel 1-412-431-8300; Fax 1-412-431-5428; E-mail webmaster@paintsquare.com