Cyclopolymerizable monomers (CPMs) were discovered about 70 years ago by Butler et al., but are rarely described in the field of photopolymerization up to now. We have developed tertiary amine-based CPMs that undergo complete cyclopolymerization, forming linear polymer chains with cyclic structures in the backbone. Compared to similar monofunctional methacrylates, they show significantly improved reactivity and high double-bond conversions. The higher reactivity could be assigned to the formation of a radical on a secondary carbon atom. Furthermore, significantly reduced shrinkage has been observed.

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