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.

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


CHLOR*RID International Inc.
Free Webinar

Learn about soluble salts, along with a discussion on allowable levels.
More information at
www.chlor-rid.com,

800-422-3217


Harsco
BLACK BEAUTY® App

Download the free app for BLACK BEAUTY® Abrasives. Explore all the features from the palm of your hand.
Toll Free: 1-888-733-3646


KTA-Tator, Inc. - Corporate Office
KTA-TATOR LABORATORY SERVICES

• Coating failure analysis
• Independent
  comparative testing
• Accelerated
  weathering testing
• Toxic metals testing
• A2LA Accredited
800-245-6379


Fischer Technology Inc.
MP0R with rotating display screen

Automatic rotating display screen just like your smart phone. Click for Video
Call 800-243-8417


Clemco Industries Corp.
Global engineering-trusted solutions

For more than 70 years, Clemco has provided the highest quality blast equipment with a total commitment to comfort and safety.


WINOA Group
W Abrasives : Bullets for cost killers

WA COST is the right solution for cost killers who want to reduce their blasting costs. Visit us during the GIFA (Hall15 - D14).


Chicago Corrosion Group
Vendor-neutral corrosion consulting

What you don’t know about painting is costing you a fortune. Call today to see how CCG’s vendor-neutral, owner’s advocacy saves our clients millions.


Wasser High-Tech Coatings Inc.
Wasser Coatings Protect

Wasser Coatings offer a complete range of Moisture Cure Urethane (NEPCOAT approved) systems in addition to Polyurea membranes and linings(NSF).
www.wassercoatings.com

 
 
 
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