Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > 'Molecular levers' may make materials better

Abstract:
In a forced game of molecular tug-of war, some strings of atoms can act like a lever, accelerating reactions 1000 times faster than other molecules. The discovery suggests that scientists could use these molecular levers to drive chemical and mechanical reactivity among atoms and ultimately engineer more efficient materials.

'Molecular levers' may make materials better

Durham, NC | Posted on December 23rd, 2012

"We are interested in designing new, stress-responsive materials, so we are trying to develop reactions that are very slow normally but that can be accelerated efficiently by force," said Duke chemist Steve Craig, who headed the research.

In recent experiments, Craig and his team found that a molecule made with a polynorbornene backbone can act as a lever to open a ring embedded within the molecule 1000 times faster than a similar ring being tugged at on a polybutadiene scaffold. The results, which appear Dec. 23 in Nature Chemistry, suggest that a simple change in the backbone may affect the how fast mechanically assisted reactions occur.

Scientists are interested in this type of molecular tug-of-war because many materials break down after repeated cycles of tugging, stress and other forces. "If we can channel usually destructive forces into constructive pathways, we could trigger reactions that make the material stronger when and where it is most useful," Craig said. Researchers might then be able to extend the material's lifetime, which might in the long term have applications ranging from composites for airplane frames to biomedical implants.

In the experiment, Craig, who is a professor and chair of the chemistry department, and his team used the equivalent of microscopic tweezers to grab onto two parts of atomic chains and pulled them so that they would break open, or react, in certain spots. The team predicted that one molecule would react more efficiently than the other but was surprised to find that the force-induced rates differed by three orders of magnitude, an amount that suggests that the polynorbornene backbone can actually accelerate forced reactions the way a crowbar quickens pulling a nail from a wall.

Craig said changes to the molecular group undergoing the reaction may have a much smaller effect than changes to nearby, unreactive molecules like those on the backbone. It is also a good starting point to identify other molecular backbones that are easy to make and have the largest response to changes in nearby reactions, features Craig said might help in developing even better, more responsive materials.

The research was supported by the U.S. Army Research Laboratory, the Army Research Office and National Science Foundation.

Citation: "A Backbone Lever Arm Effect Enhances Polymer Mechanochemistry." (2012) Klukovich, H. et al. Nature Chemistry. AOP. DOI: 10.1038/NCHEM.1540

####

For more information, please click here

Contacts:
Ashley Yeager

919-681-8057

Copyright © Duke University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Feynman Prize Winners Announced! April 26th, 2015

New ASTM Standards Will Help Educate Present and Future Nanotechnology Workforces April 26th, 2015

Heat makes electrons’ spin in magnetic superconductors April 26th, 2015

QD Vision Wins 2015 Bronze Edison Award for Color IQ™ Quantum Dot Technology April 26th, 2015

Chemistry

Scientists Use Nanoscale Building Blocks and DNA 'Glue' to Shape 3D Superlattices: New approach to designing ordered composite materials for possible energy applications April 23rd, 2015

New class of 3D-printed aerogels improve energy storage April 22nd, 2015

Expanding the reach of metallic glass April 22nd, 2015

Protein Building Blocks for Nanosystems: Scientists develop method for producing bio-based materials with new properties April 17th, 2015

Govt.-Legislation/Regulation/Funding/Policy

SEFCU, SUNY Poly CNSE Announce Winning Student-Led Teams in the 6th Annual $500,000 New York Business Plan Competition April 25th, 2015

Northwestern scientists develop first liquid nanolaser: Technology could lead to new way of doing 'lab on a chip' medical diagnostics April 25th, 2015

ORNL reports method that takes quantum sensing to new level April 23rd, 2015

Electron spin brings order to high entropy alloys April 23rd, 2015

Discoveries

Heat makes electrons’ spin in magnetic superconductors April 26th, 2015

SEFCU, SUNY Poly CNSE Announce Winning Student-Led Teams in the 6th Annual $500,000 New York Business Plan Competition April 25th, 2015

Northwestern scientists develop first liquid nanolaser: Technology could lead to new way of doing 'lab on a chip' medical diagnostics April 25th, 2015

Fast and accurate 3-D imaging technique to track optically trapped particles April 24th, 2015

Materials/Metamaterials

Electron spin brings order to high entropy alloys April 23rd, 2015

Scientists Use Nanoscale Building Blocks and DNA 'Glue' to Shape 3D Superlattices: New approach to designing ordered composite materials for possible energy applications April 23rd, 2015

Surface matters: Huge reduction of heat conduction observed in flat silicon channels April 23rd, 2015

Nanoparticles Used to Improve Mechanical, Thermal Properties of Cellulose Fibers April 23rd, 2015

Announcements

Feynman Prize Winners Announced! April 26th, 2015

New ASTM Standards Will Help Educate Present and Future Nanotechnology Workforces April 26th, 2015

Heat makes electrons’ spin in magnetic superconductors April 26th, 2015

QD Vision Wins 2015 Bronze Edison Award for Color IQ™ Quantum Dot Technology April 26th, 2015

Military

Electron spin brings order to high entropy alloys April 23rd, 2015

Engineer improves rechargeable batteries with MoS2 nano 'sandwich' April 18th, 2015

Cobalt film a clean-fuel find: Rice University discovery is efficient, robust at drawing hydrogen and oxygen from water April 15th, 2015

MIT sensor detects spoiled meat: Tiny device could be incorporated into 'smart packaging' to improve food safety April 15th, 2015

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project