通过"移植"方法合成分子刷子:ATRP和点击反应的组合
Haifeng Gao1, Krzysztof Matyjaszewski
1Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, USA.
Journal of the American Chemical Society
|May 1, 2007
概括
研究人员使用原子转移激素聚合 (ATRP) 和点击化学合成了密集的分子刷. 他们通过优化侧链特性和反应条件来实现高接种密度,创造了先进的聚合物架构.
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
- 宏观分子工程 宏观分子工程
背景情况:
- 分子刷,也称为瓶刷大分子,是具有密集接种侧链的聚合物.
- 这些复杂的架构提供了独特的特性,但需要控制的合成方法.
- "接种"方法允许创建明确的聚合物结构.
研究的目的:
- 通过ATRP和点击化学的组合,合成具有高移植密度的分子刷.
- 为了研究侧链特征和反应静脉测量对接种密度的影响.
- 创建具有可调节属性的高级聚合物架构.
主要方法:
- 通过ATRP合成线性聚二乙基甲酸 (PHEMA).
- 通过化对PHEMA与基基组的功能化.
- 亚齐多终结的聚合物侧链 (包括PEO,聚烯,聚乙烯,聚乙烯酸) 与PHEMA-alkyne骨干的点击合.
主要成果:
- 在3小时内成功合成了高达88%的移植密度的分子刷.
- 高种植密度与使用较低的分子量,较薄的侧链 (例如,PEO-N3,Mn = 775 g/mol) 和高比相关.
- 由此产生的刷共聚合物平均每分子约有186个侧链,分子重量约为190公斤/mol.
结论:
- 与ATRP和点击化学相结合的"移植"方法对于合成密集的分子刷子是有效的.
- 移植密度可以通过调整侧链分子量,化学结构和反应固化度来控制.
- 这项研究为先进的聚合物架构提供了一条途径,在各种领域都有潜在的应用.
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