在氨酸吊聚烯 (L-氨酸) 染料中的超灭:依赖分子量,溶剂和聚合
Liangde Lu1, Roger Helgeson, Robert M Jones
1Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287, USA.
Journal of the American Chemical Society
|January 17, 2002
概括
聚合物长度显著影响光火. 较长的聚L-氨酸 (聚合物) 显示出对火的敏感性增加,而J-聚合物形成增强了对先进材料应用的这种效果.
科学领域:
- 聚合物化学 聚合物化学
- 光物理学的光学物理学
- 材料科学 材料科学 材料科学
背景情况:
- 具有可调节光物理性质的聚合物材料对于先进的应用至关重要.
- 了解多电解质中的光灭机制是控制其光学行为的关键.
- 聚 (L-氨酸) 提供了一个多功能平台,用于研究带电聚合物的结构性质关系.
研究的目的:
- 合成一系列具有不同重复单位数 (N(PRU)) 的聚L-氨酸.
- 为了研究这些多分子 (L-lysines) 和一种单体氨酸染料的光物理性质,特别是光火性.
- 分析聚合物长度,J聚合和火效率之间的关系.
主要方法:
- 聚L-氨酸的合成) 与NPRU) 范围从6到900.
- 在水性二甲基硫氧化物溶液中进行光物理研究.
- 光火实验使用9,10-二二二二硫酸盐作为电子受体火器.
- 灭常数 (K(SV)) 的确定和吸收和光谱的分析.
主要成果:
- 灭常数 (K(SV)) 与N(PRU单调增加,从单体的630 M(-1) 增加到聚合物中的1.2 x 10(9) M(-1) 与N(PRU) ~900.
- 具有N (PRU) > 100的聚L-氨酸表现出J-聚合物的吸收和光,增强火易感性.
- 通过单个火器灭的有效刺激子域在强烈J聚合的聚合物中达到大约100个重复单位.
结论:
- 聚合物长度是一个关键因素控制光火在聚L-lysines).
- 在较长的多 (L-lysines) 中的J聚合显著提高了火效率.
- 这项研究提供了对光聚电解质中超级灭机制的见解,使响应材料的合理设计成为可能.
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