单元催化剂/启动器用于乳的有机催化环开放聚合
Szilárd Csihony1, Darcy A Culkin, Alan C Sentman
1Center for Polymeric Interfaces and Macromolecular Assemblies, Department of Chemistry, Stanford University, Stanford, California 94305, USA.
Journal of the American Chemical Society
|June 23, 2005
概括
1,3-dimesitylimidazolin-2-ylidene的新酒精添加物是稳定的固体,在溶液中释放碳. 这些添加物有效催化乳化物的环开聚合,产生具有受控性质和复杂结构的聚合物.
科学领域:
- 有机金属化学 有机金属化学
- 聚合物化学 聚合物化学
背景情况:
- N-异环碳 (NHCs) 是多功能联体和催化剂.
- 控制的聚合需要稳定和高效的启动器.
研究的目的:
- 为了合成和描述1,3-dimesitylimidazolin-2-ylidene的新型酒精添加物.
- 为了评估它们作为乳化物聚合的单元催化剂的性能.
主要方法:
- 主要和次要酒精添加物的合成.
- 使用光谱技术进行表征.
- 乳化物的环开聚合.
主要成果:
- 得到了稳定的固体 adducts.
- 吸管很容易在溶液中释放自由碳素.
- 在温和条件下有效催化乳化物聚合.
- 实现了受控的分子重量和狭窄的多分散性.
- 使用多功能 adducts 准备复杂的多分子 (乳酸) 架构.
结论:
- 1,3-dimesitylimidazolin-2-ylidene的酒精添加物是有效的单组分启动剂.
- 它们使得具有可调节性质的聚乳酸的受控合成成为可能.
- 创造先进的聚合物架构的潜力.
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