用于二氧化和二氧化碳交替共聚的催化剂:结合了高活性和选择性
Claire T Cohen1, Tony Chu, Geoffrey W Coates
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, NY 14853-1301, USA.
Journal of the American Chemical Society
|August 4, 2005
概括
高活性催化剂使氧化物和二氧化碳的高效,活体共聚化能够产生具有受控微观结构的聚碳酸. 这些催化剂提供了增强的活性和选择性,即使在低二氧化碳压力下.
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
- 催化剂是一种催化剂.
背景情况:
- 开发有效的催化剂来利用二氧化碳对于可持续化学至关重要.
- 聚烯碳酸 (PPC) 是一种具有潜在应用的可生物降解聚合物.
- 活体共聚合提供了对聚合物性质的精确控制.
研究的目的:
- 为了合成和表征新的盐复合物作为催化剂.
- 为了研究活的,交替的氧化物 (PO) 和CO2的共聚化.
- 探索催化剂结构和共催化剂对PPC特性的影响.
主要方法:
- (盐酸) CoX 复合物的合成 (X = 化物或碳酸盐).
- 使用各种催化剂和催化剂 ([PPN]Cl,[PPN][OBzF(5)) 的共聚化反应.
- 分析聚合物微结构,分子量分布 (MWD) 和催化活性.
主要成果:
- 盐复合物是生命的高度活性催化剂,PO和CO2的交替共聚化.
- PPC生产的产品具有很高的区域规律性 (高达99%的碳酸链接) 和狭窄的MWD.
- 催化剂显著增强了催化活性,立体选择性和区域选择性,实现了高周转频率 (高达1100小时-1).
- 单体和催化剂立体化学极大地影响PPC微结构,使控制区域规律性和联合丰富成为可能.
结论:
- 新型盐催化剂和共催化剂系统在PO/CO2共聚合中提供了前所未有的效率和控制.
- 这项工作推进了功能性聚乙烯碳酸盐与定制微观结构的合成.
- 这些发现为二氧化碳提升为有价值的聚合物提供了一个有希望的途径.
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