ORGN 104 |
| Mechanochemical triggers based on the electrocyclic ring openeing of benzocyclobutenes have been designed and synthesized. These triggers are capable of diverting the mechanical energy stored in a stressed polymer into useful chemical pathways such as healing or toughening reactions. The triggers were incorporated into linear poly(ethylene glycol) polymers and subjected to elongational stress. It was found that the triggers react well below ambient temperature with increasing reaction rate with increasing MW. 13C labeling revealed that stress influences the rotational preference for electric ring opening. While trans benzocyclobutenes undergo contotatory ring opening, elongational stress induces a disrotatory ring opening in cis disubstituted benzocyclobutenes. |
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Materials, Devices, and Switches
1:00 PM-5:00 PM, Sunday, 10 September 2006 Moscone Center -- Room 132, Oral
Division of Organic Chemistry |