立体复合体形成的立体正规聚乙烯图书馆 通过异构化驱动的阴离子环开放聚合方式实现
Pengjun Yuan1,2, Yongliang Xia2, Xi Zhang2
1Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, College of Chemistry, and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, China.
Angewandte Chemie (International ed. in English)
|June 3, 2025
概括
研究人员使用无金属启动器从奇拉性硫诺中开发出立体正规聚乙烯. 这一突破使新的含硫高点聚合物立体复合物成为可能,推动了可持续的聚合物科学.
科学领域:
- 聚合物化学 聚合物化学
- 可持续的高分子.
- 超分子化学 超分子化学
背景情况:
- 超分子立体复合是可持续聚合物的关键,含氧聚合物得到了充分的研究.
- 含硫聚合物是一种新的可持续材料类别,由于合成立体规律聚合物和低超分子相互作用的挑战,其研究不足.
研究的目的:
- 为了克服合成立体正规含硫聚合物的挑战.
- 为了探索聚乙中的超分子立体复合.
- 开发具有增强性能的新型可持续聚合物.
主要方法:
- 使用一种无金属阴离子启动器,[Et3O]+[B(C6F5)4]-,用于受控异构化驱动的环开聚合物 (IROP).
- 研究了九个例子的奇拉五个成员的thionolactones.
- 采用独特的单体稳定SN2传播机制来控制立体规律性并最大限度地减少种族化.
主要成果:
- 获得了奇拉类硫黄的受控 IROP,产生具有高异性 (80.0%-99.5%) 的立体正规聚乙烯.
- 揭示了两种新的聚乙烯立体复合物,其化温度高 (117.0-161.0°C).
- 揭示了立体复杂形成机制的基本方面以及影响立体复杂化能力的关键因素.
结论:
- 建立了一种合成立体正规聚乙烯的新方法,使人们能够获得一类新的可持续聚合物.
- 证明了高化的聚乙烯立体复合物的形成,扩大了超分子聚合物应用的范围.
- 提供了对结构-立体复合关系和控制聚乙烯中立体复合物的形成的因素的关键见解.
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