通过侧链分支模式调节两性多块共聚物的分子几何和溶液自组
Liying Kang1, Albert Chao2, Meng Zhang2
1School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Journal of the American Chemical Society
|April 6, 2021
概括
卷状晶体双块共聚体的N替代物结构显著影响它们的自我组装. 线性侧链形成微花,而分支链形成六角纳米板,使可调节的纳米材料架构成为可能.
科学领域:
- 聚合物化学
- 材料科学
- 超分子化学
背景情况:
- 通过溶液自组装提供可调节的等级纳米结构.
- 在决定这种自我组装的过程中,N替代物结构的作用仍然不完全理解.
- 了解N替代物效应对于设计功能性多类纳米材料至关重要.
研究的目的:
- 调查N替代物结构如何影响双块共聚体的晶体包装和等级自组.
- 为了比较多类与线性与分支形N替代物的自我组装行为.
- 阐明不同纳米结构形成的机制.
主要方法:
- 两个双块共聚的设计和合成:聚甲基-b-聚甲基 (PNMG-b-PNOG) 和聚甲基-b-聚甲基 (PNMG-b-PNEHG).
- 使用依赖时间的小/广角X射线散射 (SAXS/WAXS) 分析晶体包装和自组装.
- 使用微观成像技术对产生的纳米结构进行表征.
主要成果:
- PNMG-b-PNOG与线性N-octylglycine形成了高度有序的晶体块,导致由纳米丝带组成的微花形态.
- PNMG-b-PNEHG,与分支N-2-乙基-1-糖,表现为柱状六角液晶半相,导致六角纳米片.
- 基于N替代物架构的微花和六角纳米板形成的独特自组装机制被确定.
结论:
- N-替代物架构 (线性与分支) 深刻影响了双块共聚的晶体包装和层次溶液自组装.
- 定制N替代物为控制聚基纳米材料的几何和层次结构提供了有效的策略.
- 这项研究推进了用于各种应用的复杂多纳米结构的设计原理.
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