催化,在融中的聚烯的特定区域功能化
Yuichiro Kondo1, Domingo García-Cuadrado, John F Hartwig
1Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, USA.
Journal of the American Chemical Society
|February 14, 2002
概括
催化玻利化通过向聚合物侧链添加玻利基组来修改聚烯. 随后的氧化引入基团,增强聚合物的特性,如玻璃过渡温度.
科学领域:
- 聚合物化学 聚合物化学
- 有机金属化学 有机金属化学
- 材料科学 材料科学 材料科学
背景情况:
- 多聚烯是多功能聚合物,但它们的功能化可能具有挑战性.
- 选择性修改聚合物侧链对于定制材料特性至关重要.
- 基玻利化为聚合物功能化提供了一个潜在的途径.
研究的目的:
- 为了研究聚乙烯 (PEE) 的催化终端选择性化.
- 为了使PEE与基具有功能性,并随后将其转化为基.
- 评估这种修改对聚合物特性的影响,例如分子量和玻璃过渡温度.
主要方法:
- 使用 bis-pinacoldiboron 和 [Cp*RhCl2]2 催化剂的 PEE 的催化玻利化.
- 氧化玻里化PEE以引入基组.
- 使用NMR光谱,MALDI-MS,GPC和Tg测量的表征.
主要成果:
- 成功实现了PEE的终端选择性玻里化.
- 基聚合物的基化产生了具有终端基组的聚合物.
- 聚合物分子重量和聚分散性基本保持不变.
- 观察到玻璃过渡温度 (Tg) 升高至50°C.
结论:
- 同质,催化和选择性基功能化对于修改多聚烯是有效的.
- 氧化后的终端化是一种可行的方法,用于将基组引入多聚烯.
- 这种修改策略可以显著提高聚合物热性能.
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