Microwave-assisted polymerizations: From discovery to upscaling

The cationic ring-opening polymn. of 2-oxazolines is a versatile method for the synthesis of well-defined polymers, but it is generally a very slow polymn. method. In this contribution, we will discuss the use of microwave irradn. to accelerate the polymn. of 2-ethyl-2-oxazoline. Ref. expts. were performed with thermal heating to address and understand the obsd. acceleration under microwave irradn. In addn., the scale-up of the microwave-assisted polymn. procedure will be discussed in detail using both monomode and multimode microwave synthesizers. The first part will deal with the scale-up in batch mode from 1 mL via 50 mL to 250 mL. The second upscaling part will address the use of continuous flow microwave reactors to scale up the microwave-assisted cationic ring-opening polymn. of 2-ethyl-2-oxazoline. In addn., the residence time distributions were detd. to understand the continuous flow processes in more detail. [on SciFinder (R)]