在螺旋式Si-Si键聚合物聚合物聚合物中进行手术逆转
Nozomu Suzuki1, Michiya Fujiki, Ruth Kimpinde-Kalunga
1Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara, 630-0192, Japan.
Journal of the American Chemical Society
|August 8, 2013
概括
螺旋型聚烯聚合物的手术性质受到侧链长度和溶剂的影响. 一个关键的n-propyl侧链长度使得依赖于溶剂的手术逆转成为可能,理论模型可以预测.
科学领域:
- 聚合物化学 聚合物化学
- 超分子化学 超分子化学
- 频谱学是一种光谱学.
背景情况:
- 螺旋型聚合物表现出独特的手术特征.
- 了解控制聚合物聚合物的光学性质的因素对于材料科学至关重要.
- 之前的研究已经探讨了螺旋型多晶体,但缺乏对聚合诱导的手术变化副作用链效应的详细分析.
研究的目的:
- 为了研究状基侧链长度对螺旋型聚烯聚合物的手术性质的影响.
- 确定共溶剂分量的作用在调节手术行为的作用.
- 开发和验证一个理论模型,用于预测这些系统中的手术逆转.
主要方法:
- 合成具有不同阿基拉性基侧链 (乙基至n-基) 的多[基--S) -2-甲基基].
- 循环二重化 (CD) 光谱法用于分析聚合物聚合物的光学特性.
- 理论计算使用胆固醇硬核模型和激子性方法的组合,包括TD-DFT (B3LYP, 6-31G(d)) 在十体模型上.
主要成果:
- 聚烯聚合物的CD光谱中的切罗普学标志取决于achiral侧链长度和辅溶剂分数.
- n-propyl侧链呈现出一个关键的长度,导致聚合时依赖溶剂的手术逆转.
- 理论模型成功地预测了观察到的侧链长度依赖的手术逆转.
结论:
- 状侧链长度是螺旋型聚烯聚合物中手术性质的关键决定因素.
- 溶剂环境在控制聚合诱导的手术逆转方面发挥着重要作用.
- 结合的理论方法为理解和预测螺旋聚合物系统中手术现象提供了强大的工具.
相关概念视频
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