对大型单晶共价有机框架进行超快超临界溶液热聚合
Jiang Sun1,2, Xuejun Wang1,2, Qiankun Wang1,2
1State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, China.
Nature protocols
|November 24, 2023
概括
研究人员开发了一种使用超临界二氧化碳 (sc-CO2) 的超临界溶热方法,以快速合成高质量的晶体聚合物材料. 这种高效的聚合技术可以产生具有各种应用所需的特性的单晶.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 像共价有机框架 (COF) 这样的晶体聚合物材料对于催化,电子和分离的应用至关重要.
- 在聚合物中通过聚合实现高晶度和大粒度具有挑战性,通常会产生无形或不良晶体的产品.
- 在聚合过程中精确控制分子组装成单晶,对于结构性质关系研究和实际应用至关重要.
研究的目的:
- 开发一种高效和快速的聚合策略,用于合成高或单晶聚合物材料.
- 克服传统聚合方法的局限性,即产生无形或小粒度的晶体产品.
- 通过聚合,展示一种用于精确组装有机分子成单晶的新方法.
主要方法:
- 一种使用超临界二氧化碳 (sc-CO2) 作为聚合物的反应介质的超临界溶热方法.
- 与传统有机溶剂相比,采用sc-CO2,它具有高扩散性和低粘度,以加速晶体生长.
- 详细的逐步程序为单体分散制备,在sc-CO2中的聚合,以及随后的单晶的净化和表征.
主要成果:
- 通过sc-CO2方法成功合成了六种具有多种拓,链接和晶体结构的共价有机框架.
- 合成的单晶体表现出极化光发光和第二和生成,证实了它们高质量的晶体性质.
- 在聚合后1-5分钟内实现了亚毫米尺寸单晶的快速生长,整个过程大约在4小时内完成.
结论:
- 超临界溶热法为合成高质量的晶体聚合物材料提供了一种高效,快速和环保的方法.
- 这种技术具有优势,包括高生产率,工业兼容性和易于访问,使其适用于研究和潜在的工业应用.
- 通过聚合快速生产单晶的能力为先进材料开发和结构性质研究开辟了新的途径.
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