U.S.-Germany Cooperative Research on Polar Diradicals in Cycloaddition and Polymerization Reactions, using Electron- Spin Resonance

9224127 Hall该奖项支持亚利桑那大学的H. K. Hall教授和两位博士后研究员与德国埃森大学有机化学研究所的H. G. Korth博士和R. Sustmann教授在聚合物化学研究方面的合作。他们对富电子烯烃和贫电子烯烃混合时引发自发聚合的机理很感兴趣。美国小组对聚合物的理论工作和动力学研究表明，存在一种中间形式，可能是双自由基。这反过来又引发键的形成并产生聚合物。证实这一理论的缺失环节是对起始双基的直接观察；利用电子自旋共振（ESR）光谱学，这是可能的。该项目的德国参与者在ESR方面贡献了大量专业知识，这将使观察和识别这些难以捉摸的双基物种成为可能。本研究解决了聚合物研究中的一个基本问题。这位美国研究者在了解是什么引发了某些类型的聚合反应方面做出了重要的开创性贡献。与德国研究人员拟议的合作将提供有关这一复杂过程的新信息，并提高他的生产和创新研究计划。＊＊＊

9224127 Hall This award supports Professor H. K. Hall, Jr. and two postdoctoral research associates from the University of Arizona to collaborate in polymer chemistry research with Dr. H. G. Korth and Professor R. Sustmann of the Institute for Organic Chemistry of the University of Essen, Germany. They are interested in the mechanism of initiation of spontaneous polymerizations that occur when electron-rich and electron-poor olefins are mixed. Theoretical work and kinetic studies on polymers by the U.S. group suggest that there is an intermediate form which may be a diradical. This in turn initiates the formation of bonds and produces the polymer. The missing link to confirm the theory is the direct observation of the initiating diradicals; this would be possible with electron-spin resonance (ESR) spectroscopy. The German participants in the project contribute substantial expertise in ESR that will make it possible to observe and identify these elusive diradical species. This research addresses a fundamental question in polymers research. The U.S. investigator has made important and ground-breaking contributions toward understanding what initiates certain types of polymerization reactions. The proposed collaboration with German investigators will produce new information on this complex process and enhance his productive and innovative research program. ***