在动力控制下通过活体结晶驱动的块共聚合物自我组装来分支的微粒
Huibin Qiu1, Yang Gao, Van An Du
1School of Chemistry, University of Bristol , Bristol BS8 1TS, United Kingdom.
Journal of the American Chemical Society
|January 14, 2015
概括
研究人员通过调整聚合物长度和溶剂条件来控制聚烯二甲基 (PFDMS) 微粒的形状和结构. 这允许通过结晶驱动自组装 (CDSA) 实现可调节的纳米结构.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
背景情况:
- 类似纤维的细胞从双块共聚合物中自组装.
- 聚烯二甲基 (PFDMS) 在这些微粒中形成晶核.
- 控制菌形态对于先进的材料应用至关重要.
研究的目的:
- 调查聚合物特性和溶剂条件对菌形态学的影响.
- 探索活体结晶驱动自组装 (CDSA) 的机制.
- 为了实现可调节的纳米结构与不同的冠状化学.
主要方法:
- 合成的聚烯二甲基 (PFDMS) 双块共聚合物,具有不同的PFDMS块长度.
- 利用活体结晶驱动的自我组装 (CDSA) 通过向种子微粒添加unimers.
- 改变溶剂的极性和温度,以研究小胞形成和形态.
- 使用对形态学和化学敏感的技术分析了微粒结构.
主要成果:
- 微粒芯宽度和形状 (矩形到圆形) 可通过PFDMS聚合度和冠状元块化学调节.
- 微细胞形态 (线性与分支) 高度依赖于溶剂极性和温度.
- 线性微粒在较少的极性溶剂/较高的温度下形成;分支微粒在较多的极性溶剂/较低的温度下形成.
- 形成了有分支的微粒和具有独特的冠状化学的块,包括两性纳米结构.
- 在非平衡条件下,分支结构似乎是动态捕获的形态学.
结论:
- 该研究表明通过CDSA精确控制PFDMS菌根形态.
- 可以实现具有复杂架构和功能的可调节纳米结构.
- 了解溶剂和温度的作用是指导自组装途径的关键.
- 这项工作为设计具有定制性质的先进纳米材料提供了一条途径.
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