由冲击波触发的聚合物混合物中的超快速质子转移
Yi Ren1, Alexandr A Banishev1, Kenneth S Suslick1
1Department of Chemistry and ‡Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|March 3, 2017
概括
冲击波引发了聚合物中的超快速质子转移. 这种使用尼罗河红色染料观察到的现象导致特定聚合物混合物的离子对形成和明显的光谱变化.
科学领域:
- 物理化学
- 材料科学
- 化学动力学
背景情况:
- 超快的质子转移在化学反应中至关重要.
- 冲击波提供一种独特的方法来诱导快速的化学变化.
- 在极端条件下探测分子动力学需要敏感的技术.
研究的目的:
- 在聚合物混合物中研究冲击诱导的超快质子转移.
- 使用尼罗河红色染料作为冲击压缩效应的探测器.
- 了解聚合物极性和密度在质子转移中的作用.
主要方法:
- 通过高速冲击产生冲击波 (≥0.8 km·s-1).
- 使用尼罗河红色 (NR) 作为聚合物极性和密度变化的光谱探针.
- 在含有质子捐赠者和受体的聚合物混合物中分析NR的光谱红移.
主要成果:
- 尼罗河红色 (NR) 呈现出由于密度和极性增加而引起的聚合物红色偏移.
- 聚4-乙烯 (PVP) 和的混合物显示出异常的NR红移.
- 这种多余的红移,在约10纳秒内出现,表明从到PVP的冲击触发的质子转移.
结论:
- 超快速的质子转移可以通过地面电子状态的冲击波来启动.
- 通过冲击触发的质子转移形成的离子对可以通过光谱检测.
- 这项研究展示了一种用于研究缩相中的快速化学动态的新方法.
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