乳化物的氧控制的聚合,由铁 bis (氧) 复合物 bis (氧) 和铁 bis (氧) 复合物催化
Ashley B Biernesser1, Bo Li, Jeffery A Byers
1Eugene F. Merkert Chemistry Center, Department of Chemistry, Boston College , 2609 Beacon Street, Chestnut Hill, Massachusetts 02467, United States.
Journal of the American Chemical Society
|October 1, 2013
概括
双胺酸铁催化剂有效聚合乳化物,表现出生活特征. 催化剂活性取决于氧化物捐赠者,并且可以通过氧化还原控制可逆地打开/关闭聚合.
科学领域:
- 有机金属化学 有机金属化学
- 聚合物科学 聚合物科学
背景情况:
- 双胺连接物是过渡金属催化剂的多功能支架.
- 铁复合物为高分子化提供了贵金属催化剂的成本效益和毒性较低的替代品.
研究的目的:
- 合成和研究用于 (rac) - 乳化物聚合的双胺 (pyridine) 铁双氧化物 (alkoxide) 复合物.
- 为了阐明由这些铁复合体启动的乳酸盐聚合的机制.
- 探索催化剂结构和氧化还原状态对聚合活性和控制的影响.
主要方法:
- 二氧化铁二氧化氧化复合物的合成.
- 使用合成的铁催化剂,对 (rac) - 乳化物进行环开聚合.
- 动力学研究和分子量分析 (GPC) 以确定聚合率和聚合物特性.
- 机理学研究,包括连接物交换和氧化还原实验.
主要成果:
- 催化剂活性对氧化的电子特性敏感,电子捐赠组增强了聚合率.
- 聚合物表现出活体过程的特征,包括狭窄的分子量分布和线性分子量转换关系.
- 机理学研究表明,铁二氧化和铁二氧化复合物的启动途径不同.
- 铁催化剂 (Fe ((II) /Fe ((III)) 的氧化还原处理允许可逆切换催化活性.
结论:
- 双胺酸铁双氧化物复合物是 (rac) - 乳化物的活聚合物的有效催化剂.
- 催化剂的性能和机制可以通过连接物修饰和氧化还原控制进行调整.
- 这项工作为开发可切换的铁基催化剂为受控聚合物合成提供了基础.
相关概念视频
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