Design of novel photobase generators upon violet LEDs and use in photopolymerization reactions

Publication date: 25 August 2017
Source:Polymer, Volume 124
Author(s): Mariem Bouzrati-Zerelli, Michel Frigoli, Frédéric Dumur, Bernadette Graff, Jean Pierre Fouassier, Jacques Lalevée
Two new near-UV and visible-light-sensitive photobase generators (PBGs) are synthesized and investigated. They are built on a near-UV and visible light sensitive (E)-3-(2,2′-bithiophen-5-yl)-2-cyanoacrylic acid chromophore and a latent strong base such as 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD). Upon irradiation, decarboxylation occurs and the base is released. The anionic curing of epoxy/thiol as well as thiol/divinylsulfone formulations in the presence of these PBGs under LEDs at 385 and 405 nm is studied. More than 60% of conversion of the thiol and epoxy functions is achieved upon LED@385 nm without any post baking.

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