像拉斯伯雷一样的共价有机框架-聚合物颗粒的合作合成,具有辐射单晶颗粒方向
Pauline Salaün1, Alexandre Fadel2, Mario Pelaez-Fernandez1
1UMR 8207 - UMET - Unité Matériaux Et Transformations, CNRS, INRAE, University of Lille, Ecole Centrale, Lille, F-59000, France.
Small (Weinheim an der Bergstrasse, Germany)
|August 24, 2023
概括
本研究介绍了混合共价有机框架-聚合物颗粒,证明聚合物可以控制2D COF生长和颗粒形状. 这项创新解决了COF纳米结构合成和可加工性方面的挑战.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 聚合物化学 聚合物化学
背景情况:
- 联有机框架 (COFs) 的设计往往忽视了纳米规模的组织和可处理性.
- 合成非聚合COF纳米结构仍然是实际应用的重大挑战.
- 控制超出框架水平的COF形态对于先进的材料特性至关重要.
研究的目的:
- 报告首个混合COF-聚合物颗粒用于控制的2DCOF生长的例子.
- 为了研究聚合物特性如何影响二维酸 Ester-linked COF-聚合物颗粒的成型.
- 探索这些混合结构对COF可处理性和形态学的影响.
主要方法:
- 合成混合COF-聚合物颗粒使用catechol功能化聚合物.
- 使用扫描电子显微镜 (SEM),传输电子显微镜 (TEM) 和4D-STEM-ACOM进行表征.
- 动力学研究以了解聚合物在COF形成中的作用.
主要成果:
- 聚合物成功地操纵2D COF的生长,导致定义的粒子形态.
- 甲基聚 (Catechol-poly ((N-butyl acrylate)) 产生准球形结构,而甲基聚 (Catechol-poly ((N-isopropylacrylamide)) 则形成具有辐射粒度的树状颗粒.
- 混合颗粒表现出单晶性质,而PNIPAm的存在使其能够在没有共同结晶的情况下干燥和再悬浮.
结论:
- 聚合物可以作为调节器或模板,在COF颗粒中引入超分子自我组装.
- 这种方法创造了新的COF形态,其结构复杂性超出了框架水平.
- 开发的混合COF-聚合物颗粒提供了改进的可加工性,克服了COF应用中的关键限制.
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