聚合物分子重量通过光确定 生命周期
Antonio Garcia1, Suzanne A Blum1
1Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States.
Journal of the American Chemical Society
|December 2, 2022
概括
这项研究引入了一种新的光终身成像显微镜 (FLIM) 方法,用于在环开通转化聚合 (ROMP) 过程中实时监测聚合物分子量 (Mw). 这种技术提供了快速的,空间分辨的Mw分析,无需样本移除或溶解性问题.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 分析化学 分析化学
背景情况:
- 精确控制聚合物分子量 (Mw) 对于调整材料性能至关重要.
- 传统的Mw表征方法缺乏实时,现场和空间分辨能力,特别是对于不溶性聚合物.
- 环开放转化聚合 (ROMP) 是聚合物合成的多功能技术,但对Mw的现场监测仍然具有挑战性.
研究的目的:
- 开发一种新的光终身成像显微镜 (FLIM) 方法,用于实时的聚合物Mw确定.
- 克服监测聚合物的传统技术的局限性.
- 允许在现场进行空间分辨的Mw分析聚合物,包括不溶性聚合物.
主要方法:
- 开发一种基于FLIM的方法,使用光标记的单体 (BODIPY-norbornene) 以低度 (1在107).
- 在聚合物Mw (通过凝透色谱法确定,35570 kg/mol) 和光寿命之间建立了定量相关性.
- 该方法应用于聚甲基和聚cyclopentadiene的催化ROMP.
主要成果:
- 证明了光寿命和聚合物Mw.之间的定量关系.
- 在正在进行的ROMP期间,启用时间分辨率Mw测量在1秒内每45μm × 45μm面积.
- 通过Mw的确定实现了聚合物形态的同时表征,无论聚合物溶解度如何.
结论:
- 开发的FLIM方法为现场聚合物Mw监测提供了一种快速且非侵入性的方法.
- 这种技术克服了传统表征的关键局限性,提供空间分辨率和适用于不溶性聚合物.
- FLIM可视化是一个强大的实时理解和控制聚合过程和聚合物结构的工具.
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