Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
Faculty of Chemistry and Pharmacy, Univeristy of Regensburg, Universitätsstraßze 31, 93053 Regensburg, Germany.
J Am Chem Soc. 2022 Aug 3;144(30):13938-13945. doi: 10.1021/jacs.2c05944. Epub 2022 Jul 19.
The comprehensive real-time in situ monitoring of chemical processes is a crucial requirement for the in-depth understanding of these processes. This monitoring facilitates an efficient design of chemicals and materials with the precise properties that are desired. This work presents the simultaneous utilization and synergy of two novel time-resolved NMR methods, i.e., time-resolved diffusion NMR and time-resolved nonuniform sampling. The first method allows the average diffusion coefficient of the products to be followed, while the second method enables the particular products to be monitored. Additionally, the average mass of the system is calculated with excellent resolution using both techniques. Employing both methods at the same time and comparing their results leads to the unequivocal validation of the assignment in the second method. Importantly, such validation is possible only via the simultaneous combination of both approaches. While the presented methodology was utilized for photopolymerization, it can also be employed for any other polymerization process, complexation, or, in general, chemical reactions in which the evolution of mass in time is of importance.
全面的实时原位监测化学过程是深入理解这些过程的关键要求。这种监测有助于高效设计具有所需精确特性的化学品和材料。本工作同时利用了两种新颖的时间分辨 NMR 方法，即时间分辨扩散 NMR 和时间分辨非均匀采样。第一种方法可以跟踪产物的平均扩散系数，而第二种方法可以监测特定的产物。此外，这两种技术都可以极好的分辨率计算体系的平均质量。同时使用这两种方法并比较它们的结果，可以明确验证第二种方法中的分配。重要的是，只有通过同时结合这两种方法才有可能进行这种验证。虽然所提出的方法学用于光聚合，但它也可以用于任何其他聚合过程、络合或一般化学反应，其中随时间推移的质量演化是重要的。
