聚合物侧链尺寸和脊柱长度对超分子聚合物瓶刷的自组装的影响
Hans F Ulrich1,2, Franka V Gruschwitz1,2, Tobias Klein1,2
1Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743, Jena, Germany.
Chemistry (Weinheim an der Bergstrasse, Germany)
|March 6, 2024
概括
研究人员探索了聚合物结构如何影响水中的自我组装. 主链长度是控制纤维形成的主要因素,较长的链导致球形.
科学领域:
- 超分子化学 超分子化学
- 聚合物科学 聚合物科学
- 材料科学 是一种材料科学.
背景情况:
- 键使得有纤维的,类似瓶的聚合物组件可以产生.
- 固体排斥和超分子力之间的平衡控制了组装行为.
研究的目的:
- 调查聚合物结构参数如何影响三 (BTU) 和三 (氨) (BTP) 合物在水中的组合.
- 了解主链长度和侧链大小在形态过渡中的作用.
主要方法:
- 合成的聚合物具有不同的主链长度和侧链大小,使用可逆添加-碎片化链转移 (RAFT) 聚合.
- 使用小角度X射线散射 (SAXS) 和传输电子显微镜 (TEM) 分析组装结构.
主要成果:
- 无论是BTU还是BTP,都与聚乙烯酸 (PHEA) 形成了纤维,但在70及以上的聚合度 (DP) 时转变为球形形态.
- 主链长度是形态过渡的主要驱动因素.
- 增加的侧链大小通常促进球形形态,并阻碍聚合,尽管由于更强的相互作用,三 (氨) (BTP) 仍然形成纤维.
结论:
- 聚合物主链长度是BTU和BTP自组装中的形态学的关键决定因素.
- 侧链的大小调节了组装,更大的侧链有利于球形结构.
- 较强的分子间相互作用,如在BTP中所见,可以部分克服固体排斥,以保持纤维组合.
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