Continuous flow cationic polymerizations

As the typical highly exothermic polymerization, cationic polymerization suffers from harsh reaction conditions and poor control of polymerizations. The combination of microreactor and cation pool method or carbocation stabilization achieves improved living cationic polymerizations under mild conditions. In this review, not only cationic addition polymerizations of vinyl monomers (vinyl ether, isobutene, and diisopropenylbenzen) but also cationic ring-opening polymerizations of cyclic monomer (oxazoline) will be highlighted in the context of microreactor-based flow chemistry. Challenges and opportunities are proposed with the aim to promote the development of cationic polymerization in both academia and industry.