具有乙烯链接的动态共价宏分子恒星
Abhijeet P Bapat1, Debashish Roy, Jacob G Ray
1Department of Chemistry, Southern Methodist University, 3215 Daniel Avenue, Dallas, Texas 75275-0314, USA.
Journal of the American Chemical Society
|November 23, 2011
概括
研究人员使用可逆的乙烯键制造了动态的星形聚合物. 这些宏观分子恒星可以反复形成和分解,为先进材料提供了潜在的潜力.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
背景情况:
- 动态共价化学可以创建自我愈合和适应性的材料.
- 乙烯 Ester 是对外部刺激有反应的关键动态共价连接.
- 像恒星聚合物这样的宏分子架构为先进的应用提供了独特的特性.
研究的目的:
- 为了合成新的宏分子恒星,利用可逆的乙烯结.
- 研究这些恒星聚合物的形成,组装和解离.
- 为了证明恒星形成-解离周期的可重复性.
主要方法:
- 具有酸功能的块共聚物质的第一臂合成.
- 块共聚合物的交联与多功能二醇形成星聚合物.
- 利用与单一功能二醇的竞争性交换反应来诱导恒星解离.
主要成果:
- 成功地制备了纳米尺寸多臂恒星,其中包含乙烯核和多,N,N-二甲基胺 (PDMA) 冠状.
- 证明,通过动态共价玻乙烯结,可以控制恒星形成和解离.
- 在多个周期中确认可重复的恒星形成和解离.
结论:
- 具有可逆玻色乙链接的宏分子恒星可以被可控地形成和分离.
- 酸乙烯的动态性质允许对聚合物结构进行刺激响应的重新配置.
- 这些发现为设计可适应和可回收的聚合物材料打开了道路.
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