质子和随后的分子内结合作为一种控制链结构和调整异原子合聚合物中发光的方法
Andrew P Monkman1, Lars-Olof Pålsson, Roger W T Higgins
1Department of Physics and the Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, United Kingdom. a.p.monkman@durham.ac.uk
Journal of the American Chemical Society
|May 23, 2002
概括
在功能性聚合物中基的质子化会诱导平面性,扩展pi-conjugation和红移光学特性. 聚二二烯-co-1,4-[2,5-bis-二甲基基]) 的这种结构变化是调光电子设备的关键.
科学领域:
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
- 频谱学是一种光谱学.
背景情况:
- 质子化显著影响分子和聚合物特性.
- 了解结构变化对于调整光电子材料至关重要.
研究的目的:
- 研究质子化对特定有机分子及其相应聚合物的结构和光谱特性的影响.
- 阐明质子化影响分子平面性和pi结合的机制.
主要方法:
- 对1,4-dimethoxy-2,5-bis(2-pyridyl) benzene的质子和非质子形式的X射线晶体分析.
- 在酸性条件下对分子和聚合物聚 (poly,2,5-pyridylene-co-1,4-[2,5-bis,2-ethylhexyloxy) ]phenylene) 的光谱分析 (光学吸收和辐射).
- 聚合物制成器件的电发光研究.
主要成果:
- 1,4-dimethoxy-2,5-bis(2-pyridyl) 与四甲酸的质子化导致具有显著的分子内键的二离子盐,导致近平面化.
- 平面化分子和质子化聚合物在光学吸收和辐射光谱中表现出巨大的红移.
- 聚合物在溶液和薄膜中的质子化会诱导类似的光谱红移,辐射来自质子化部位和非质子化部位.
结论:
- 质子化,加上分子内结合,将聚合物驱动到接近平面的构造,扩展pi-conjugation.
- 这种机制为调整合聚合物的吸收和排放概况提供了一条新的途径.
- 在聚合物基电解发光器件中也观察到由质子化诱导的光谱红移.
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