Researchers at Eindhoven University of Technology (TU/e) have developed an entirely new method for starting chemical reactions. For the first time they used mechanical forces to control catalytic activity one of the most fundamental concepts in chemistry. This allowed them to initiate chemical reactions with mechanical force. This discovery paves the way to developing materials capable of repairing themselves under the influence of mechanical tension. The results of their research will be published online on 6 April 2009 in the new international journal Nature Chemistry.
The research team (Dr. Alessio Piermattei, Dr. Karthik Sivasubramanian and Dr. Rint Sijbesma) of the Institute for Complex Molecular Systems (ICMS) and the Department of Chemical Engineering and Chemistry, both at TU/e, is the first to have demonstrated that a catalyst can be switched from a dormant to an active state (see illustration) by pulling on a polymer chain, a "molecular ripcord." The researchers were able to use this catalyst to initiate a variety of chemical reactions, including polymerizations (formation of polymer chains from small molecular building blocks called monomers).
This discovery paves the way to creating self-repairing materials that strengthen under the influence of mechanical stress. If a material were to tear, for example, this would simultaneously break the metal complex in half, thereby activating the catalyst, and the material would be instantly repaired.
This work will also lead to research into other applications in which it should be possible to turn chemical reactions on and off as desired. Potential applications include the injection molding of plastic objects, where the technique could be used to simplify processing, or microscale chemical synthesis.
How does it work; weakest link
The researchers packed a catalytically active metal ion
|Contact: Dr. Rint Sijbesma|
Eindhoven University of Technology