环开放聚合N-硫酸以产生线性聚三甲胺和封闭系统块共聚物
Louis Reisman1, Elizabeth A Rowe1, Enrique M Jackson2
1Department of Chemistry and Biochemistry , The University of Alabama , Tuscaloosa , Alabama 35487-0336 , United States.
Journal of the American Chemical Society
|November 9, 2018
概括
通过活离子环开放聚合物实现了多乙烯和线性多乙烯的受控合成. 这种方法可以精确控制新型聚合物结构的分子量和分散性.
科学领域:
- 聚合物化学
- 有机合成
- 材料科学
背景情况:
- 控制的聚合技术对于开发先进的聚合物材料至关重要.
- 亚二烯为环开放聚合提供了一个独特的单体类.
- 之前的方法缺乏对聚乙和线性聚乙烯胺合成的精确控制.
研究的目的:
- 研究N-p-托利硫酸丁 (pTsAzet) 和N-o-托利硫酸丁 (oTsAzet) 的活离子环开放共聚变.
- 开发一种可控的线性聚三甲胺 (LPTMI) 途径.
- 探索使用硫酸和N-p-toluenesulfonyl-2-methylaziridine (pTsMAz) 的块共聚物的合成.
主要方法:
- 对 pTsAzet 和 oTsAzet 的离子环开放共聚.
- 用于动态监测和反应率的H NMR光谱.
- 减少托西尔组的去除以产生LPTMI.
- 对 pTsMAz 进行序列聚合,然后对 pTsAzet/oTsAzet 进行区块聚合.
主要成果:
- 合成了pTsAzet和oTsAzet的统计共聚物,其分子重量和分散度受到控制.
- 在180°C时的单体反应率为oTsAzet的1.66和pTsAzet的0.60.
- 实现了LPTMI的第一个可控合成.
- 通过利用差异化聚合温度,成功合成了一个块共聚合物,p(pTsMAz) -b-p(pTsAzet-co-oTsAzet).
结论:
- 活离子环开放共聚化提供了对多硫胺合成的良好控制.
- 降低基分裂是一种有效的方法来产生受控的分子量LPTMI.
- 硫酸和N-p-toluenesulfonyl-2-methylaziridine的不同聚合动力学使其能够轻松地合成区块共聚物.
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