基于单个单体添加的活交替环开放转化聚合物
1Department of Chemistry, Stanford University, Stanford, California 94305, United States.
Journal of the American Chemical Society
|July 17, 2015
概括
通过环开放转基因,可通过循环烯进行受控的活交替聚合. 这种方法可以产生具有精确分子量和微观结构的聚合物,避免副作用.
科学领域:
- 聚合物化学
- 有机合成
- 材料科学
背景情况:
- 环开转化聚合 (ROMP) 是一种多功能聚合物合成技术.
- 对某些单体来说,实现受控的活聚合和交替的共聚化仍然是一个挑战.
研究的目的:
- 开发用于控制ROMP的新型环单体.
- 用低压力循环烯来实现生态交替开环转化聚合 (ROMP).
- 在聚合过程中研究异位环的动态行为.
主要方法:
- 专门设计的异位环烯的合成.
- 用各种低应变周期性烯酸进行环开通转化聚合 (ROMP).
- 使用NMR光谱 (1H和13C) 和MALDI-TOFMS进行了表征.
主要成果:
- 在ROMP中选择性添加单个单体.
- 实现了与低应变周期性烯酸相交替的ROMP,产生具有受控分子量和低分散性的聚合物.
- 显示出高的微观结构规律性和由此产生的共聚物中的严格交替序列.
- 观察到异位环烯的零级动力学,表明初始添加速度快.
结论:
- 在环中精心调节环应变和固体是控制ROMP的关键.
- 这种方法为合成明确的交替共聚物提供了一个强大的新途径.
- 开发的方法可以精确地控制聚合物结构和特性.
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