Photopolymerization, Cationic

Abstract This paper reviews the main principles of cationic photopolymerization. Photoinitiators and monomers reactivity is discussed with special focus paid to iodonium salts as photoinitiators and epoxides, oxetanes, and vinylethers as monomers. The effect of water or alcohol on the structure of the polymer network and the reactivity is depicted. The so‐called kick‐starting effect of mixtures of epoxides, oxetane, and vinyl ether is described. Finally, the emerging process of photoinduced cationic frontal polymerization for the curing of thick samples is introduced.