设计,合成和自组合的聚合物与量身定制的移植分布
Alice B Chang1, Tzu-Pin Lin1, Niklas B Thompson1
1Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States.
Journal of the American Chemical Society
|November 9, 2017
概括
这项研究提出了一种新方法,用于合成具有受控结构的聚合物,使用穿透环开通转化聚合物. 这种多功能策略可以精确控制先进材料设计的移植分布和聚合物特性.
科学领域:
- 聚合物化学
- 材料科学
- 有机合成
背景情况:
- 精确控制聚合物接种密度和分布对于定制材料属性至关重要,但仍然是一个合成挑战.
- 现有的方法往往缺乏在移植聚合物中实现特定架构控制的多功能性.
研究的目的:
- 开发一种用于合成精确控制结构的移植聚合物的多功能策略.
- 研究可预测序列控制的共聚变的动力学和机制.
主要方法:
- 通过单共聚化宏和稀释剂采用接种透过环开放的转化聚合物 (ROMP).
- 研究各种稀释剂的同聚化动力学,以了解结构-反应性关系.
- 应用梅奥-易斯终端模型来确定交叉传播速率常数和反应率.
- 使用小角度X射线散射 (SAXS) 来分析自组装结构并与移植分布相关.
主要成果:
- 通过稀释剂修改证明可调整的同聚合率 (0.3682 M-1 s-1).
- 实现了广泛的宏观分子/稀释剂反应率 (0.0820),从而实现块状,梯度或随机的骨干序列.
- 合成的AB移植双块聚合物具有控制的分子形状 (形,均,反形).
- 通过SAXS展示了植入物分配对自组装结构的影响.
结论:
- 开发的ROMP策略为设计和合成具有任意架构的移植聚合物提供了一种一般方法.
- 对ROMP动力学和单体设计的洞察力扩大了分子和材料设计的可能性.
- 通过精确的结构控制来定制聚合物的特性, 控制的共聚化提供了一个强大的工具.
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