从分子到相的奇拉性转移在自组装的奇拉块共聚合物中
Rong-Ming Ho1, Ming-Chia Li, Shih-Chieh Lin
1Department of Chemical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan. rmho@mx.nthu.edu.tw
Journal of the American Chemical Society
|May 25, 2012
概括
状块共聚物 (BCP*) 自组装,将分子性转移到螺旋式纳米结构. 这一过程由微相分离驱动,产生具有可预测的手性同体相.
科学领域:
- 聚合物科学 聚合物科学
- 超分子化学 超分子化学
- 奇拉性研究 奇拉性研究
背景情况:
- 体块共聚物 (BCP*) 为创建有序体纳米结构提供了独特的机会.
- 了解BCP自组装中的性转移机制对于设计先进材料至关重要.
研究的目的:
- 为了阐明在BCP自组装过程中在不同长度尺度上进行奇拉转移的机制.
- 为了证明同基性从分子向相基性在基BCP的进化*.
- 研究微相分离在形成状螺旋相中的作用.
主要方法:
- 循环二元化 (CD) 和振动循环二元化 (VCD) 谱学,以确定分子性和螺旋形状的手性.
- 传输电子显微镜 (TEM) 断层扫描用于螺旋式纳米结构的直接可视化.
- 光谱检测分子相互作用和形状变化.
主要成果:
- 使用CD和VCD确认了分子性,识别了螺旋手性.
- 通过TEM断层扫描可视化了螺旋 (H*) 阶段的形成,并通过TEM断层扫描定义了手性.
- 观测到重要的诱导CD信号和光转移在临界微粒度以上的阿基拉烯部分.
结论:
- 从分子转移到相位的化转移在BCP*自组装中得到了证明.
- 在接口上的微相分离启动了一个扭转和转移的机制,导致H*相形成.
- 这项研究提供了对区块共聚合物中性自我组装的基本原理的见解.
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