通过阳离子结合催化控制和区域选择性环开聚合物
Tianyi Du1, Boming Shen2, Jieyu Dai1
1Beijing National Laboratory for Molecular Sciences, Center for Soft Matter Science and Engineering, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Journal of the American Chemical Society
|November 21, 2023
概括
研究人员开发了一种新的离子结合方法来控制聚二硫化物的合成.这种方法可以快速,高精度的活环开放聚合1,2-二硫.
科学领域:
- 聚合物化学
- 材料科学
- 有机合成
背景情况:
- 聚硫化物是多用途的含硫聚合物,在医学,能源和功能材料方面具有显著的潜力.
- 聚化物中的动态共价二硫化物 (S-S) 键对硫化物 (RS-) 离子具有高度反应性,阻碍了受控的聚合.
- 现有的方法难以管理硫化物链末端的反应性,这对合成线性多硫化物构成了挑战.
研究的目的:
- 通过解决硫化离子的反应性,开发一种控制线性多硫化物合成的新方法.
- 实现 1,2-dithiolanes 的快速,活环开放聚合,对分子重量分布和区域选择性的高度控制.
- 阐明聚合的机制和催化剂在控制链传播和单体添加中的作用.
主要方法:
- 使用氨基基基催化剂与硫化物链端复合的离子结合方法.
- 1,2-dithiolanes的环开放聚合
- 涉及三元复合体形成的机制研究和催化模型的理论分析.
- 聚合物的特性,包括分散性和区域选择性.
主要成果:
- 通过阴离子结合策略成功控制聚二硫化物合成,阻止硫化物链末端的反应性.
- 实现了 1,2-dithiolanes 的快速活环开放聚合,产生具有狭窄分散度 (Mw/Mn ≈ 1.1) 和高区域选择性 (Ps ≈ 0.85) 的聚合物.
- 通过机理学和理论研究确定了一种尿基硫化物三元复合物为活性催化物种.
- 证明了催化系统与各种功能组的兼容性及其从脂酸衍生物中产生半晶体聚合物的能力.
结论:
- 开发的离子结合方法通过控制硫化离子的反应性来有效控制聚合物.
- 涉及三元复合物的协同催化模型为实现高区域选择性和受控聚合提供了一个新范式.
- 这种方法为合成具有适合各种应用的先进聚硫化物材料开辟了道路.
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