POS1-0382
Development of Controlled Ring-Opening Polymerization of Lactams Using Lewis Acid
When and Where
Nov 30, -0001
12:00am - 12:00am
Presenter(s)
Yinan Gao (Nagoya University)
Co-Author(s)
Abstract
Polyamides are important engineering plastics due to their excellent mechanical properties and thermal stability, enabling widespread use in various fields. Among them, polyamide 6 (nylon 6) is a particularly important industrial polymer that is typically produced by the ring-opening polymerization (ROP) of ε-caprolactam (ε-CL). However, precise control of the structure of polyamide 6, such as molecular weight and chain-end groups, remains challenging. Conventionally, the ROP of lactams has been extensively investigated through anionic polymerization using strong bases. However, this process requires harsh reaction conditions, typically at temperatures above 200℃. Furthermore, side reactions frequently occur under these conditions, making precise control of the polymerization difficult. Consequently, the development of a controlled polymerization of lactams under milder conditions remains desirable.
In polymer chemistry, Lewis acid catalysis has found broad utility. Various polymerization reactions have been controlled based on the properties of Lewis acids, which can be tuned through their structures, such as the metal centers and ligands. Nevertheless, the application of Lewis acid catalysts to polyamide synthesis has been limited.
In this study, we investigated the ROP of ε-CL using Lewis acid catalysts by systematically varying the metal center and ligands. In addition, to control the initiation reaction and chain-end groups, we examined various initiators. As a result, appropriate Lewis acids efficiently catalyzed the polymerization of ε-CL in combination with amines as initiators, affording well-defined polyamide 6 with narrow molecular weight distributions. Controlled polymerization of other lactams was also achieved. These findings suggest that Lewis acid-mediated ROP provides a new platform for the precision synthesis of polyamides.
In polymer chemistry, Lewis acid catalysis has found broad utility. Various polymerization reactions have been controlled based on the properties of Lewis acids, which can be tuned through their structures, such as the metal centers and ligands. Nevertheless, the application of Lewis acid catalysts to polyamide synthesis has been limited.
In this study, we investigated the ROP of ε-CL using Lewis acid catalysts by systematically varying the metal center and ligands. In addition, to control the initiation reaction and chain-end groups, we examined various initiators. As a result, appropriate Lewis acids efficiently catalyzed the polymerization of ε-CL in combination with amines as initiators, affording well-defined polyamide 6 with narrow molecular weight distributions. Controlled polymerization of other lactams was also achieved. These findings suggest that Lewis acid-mediated ROP provides a new platform for the precision synthesis of polyamides.
