Scale‐Up of Microwave‐Assisted Polymerizations in Continuous‐Flow Mode: Cationic Ring‐Opening Polymerization of 2‐Ethyl‐2‐oxazoline

Microwave‐assisted polymerizations is a growing field of interest because the use of microwave irradiation instead of thermal heating was demonstrated to result in faster, cleaner, and higher yielding reactions. To overcome the one‐at‐a‐time nature of preparing polymerizations in single microwave vials and the possible scale‐up method for microwave‐assisted polymerizations, the use of continuous‐flow reactions under microwave irradiation seems to be ideal. In this contribution, we report for the first time the use of different continuous‐flow microwave reactors for polymerizations, using the cationic ring‐opening polymerizations of 2‐ethyl‐2‐oxazoline as a model system. In addition, the observed broader molecular‐weight distributions were correlated to residence time distributions of the continuous‐flow reactors that were determined using methyl orange as the flow marker. magnified image