类似树突体的聚乙烯氧化物的pH响应
Xiaoshuang Feng1, Daniel Taton, Redouane Borsali
1Laboratoire de Chimie des Polymères Organiques, Ecole Nationale Supérieure de Chimie et Physique de Bordeaux-Université Bordeaux-1-CNRS 16, Avenue Pey Berland, 33607 Pessac Cedex, France.
Journal of the American Chemical Society
|August 31, 2006
概括
研究人员使用类似树突体的聚乙烯氧化物支架与内部聚烯酸链创建了响应pH的单分子系统. 这些结构随着pH值的变化而可逆缩小和扩大,避免通过分子内复合形成聚合.
科学领域:
- 聚合物化学 聚合物化学
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
背景情况:
- 聚乙烯氧化物 (PEO) 和聚烯酸 (PAA) 已知通过非共价相互作用对pH敏感聚合.
- 控制聚合物架构是设计响应性材料和避免宏观聚合的关键.
研究的目的:
- 通过组装PEO和PAA在特定的树突状结构中,合成具有pH响应的单分子系统.
- 为了利用PAA和PEO单元之间的分子内复合,用于pH诱导的可逆尺寸变化.
- 为了避免分子间复杂化和宏观聚合.
主要方法:
- 使用阳离子环开放聚合 (AROP) 和一种新型AB(2) C分枝剂合成第五代树脂体样PEO支架.
- 通过原子转移激素聚合 (ATRP) 启动站点,使 PEO 支架的内部乙烯基组功能化为聚烯酸 (PAA) 链.
- 使用动态光散射 (DLS) 来评估pH依赖的尺寸变化,对带有PAA的树枝状PEOs进行表征.
主要成果:
- 成功合成了具有21个内部,连接连接的PAA块的水友性,树枝状PEOs.
- 证明了pH响应性行为,其中单分子系统在水中可逆收缩和膨胀.
- 证实了特定的架构防止了分子间复杂化,有利于分子内相互作用.
结论:
- 设计的树突状PEO架构有效地控制了PEO和PAA链的自组装.
- 这些单分子系统由于分子内PAA-EO复杂化而表现出可调节,可逆的pH响应性行为.
- 这种方法为创建先进的响应性聚合物材料提供了一种新的策略.
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