序列控制的聚合物通过输入驱动的环开放转化聚合物:理论,分子重量控制和单体设计
Jamie A Nowalk1, Cheng Fang1,2, Amy L Short1
1Department of Chemistry , University of Pittsburgh , Pittsburgh , Pennsylvania 15260 , United States.
Journal of the American Chemical Society
|February 5, 2019
概括
通过选择性增强的环开放转化聚合物 (SEED-ROMP) 合成测序聚合物现在是可扩展和可控制的. 这种方法可以精确控制分子量和聚合物特性,克服以前的局限性.
科学领域:
- 聚合物化学
- 材料科学
背景情况:
- 单体序列极大地影响共聚物特性,但对序列共聚物的控制合成具有挑战性.
- 之前的分步生长方法对测序的多糖乳糖酸缺乏分子量控制,可扩展性和产量可预测性.
研究的目的:
- 开发一种高效,可扩展和可控制的合成序列聚合物的方法.
- 使用一种新的聚合技术研究单体序列对聚合物的影响.
主要方法:
- 通过循环宏观素的开环转化聚合 (ED-ROMP) 合成测序聚合物.
- 在ED-ROMP中加入乙烯糖醇和转化链接剂.
- 使用闭环转化和大小微生物化制备周期性大小微生物.
- 在选择性增强 (SEED-ROMP) 的转化活性部分使用cis-olefins.
主要成果:
- 测序聚合物的多克尺度合成与受控的分子重量.
- 在SEED-ROMP中显示出第一阶段的动力学和狭窄的分散性,表明生活特征得到了增强.
- 成功制备了块共聚物,进一步证实了聚合物的生命性质.
- 计算分析显示,由于形状偏好,西斯宏环烯增强了聚合动力学.
结论:
- SEED-ROMP提供了一种通用和有效的策略,用于生产精确集成的测序段的分子重量控制的聚合物.
- 这种进步克服了先前方法的局限性,使得在聚合物科学中得到更广泛的应用.
- 这些发现为通过受控测序设计具有量身定制的散装性质的聚合物铺平了道路.
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