Cyclopolymerizable Monomers

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.

[1] F. Karasu, C. Dworak, S. Kopeinig, E. Hummer, N. Arsu, R. Liska: "Photoinitiating Monomers Based on Diacrylamides"; Macromolecules, 41 (2008), 21; S. 7953 - 7958.

[2] G. Peer, P. Dorfinger, T. Koch, J. Stampfl, C. Gorsche, R. Liska: "Photopolymerization of Cyclopolymerizable Monomers and Their Application in Hot Lithography"; Macromolecules, 51 (2018), 22; S. 9344 - 9353.

[3] G. Peer, M. Kury, C. Gorsche, Y. Catel, P. Frühwirt, G. Gescheidt, N. Moszner, R. Liska: "Revival of Cyclopolymerizable Monomers as Low-Shrinkage Cross-Linkers"; Macromolecules, 53 (2020), 19; S. 8374 - 8381.

[4] L. Ruppitsch, G. Peer, K. Ehrmann, T. Koch, R. Liska: "Photopolymerization of difunctional cyclopolymerizable monomers with low shrinkage behavior"; Journal of Polymer Science Part A: Polymer Chemistry, 59 (2021), 6; S. 519 - 531.