A glance at violet LED sensitive photoinitiators based on the spiroxanthene scaffold

Haifaa Mokbel (1) , Cyril Poriel (2) , Joëlle Rault-Berthelot (2) , Frédéric Dumur (3) , Didier Gigmes (3) , Joumana Toufaily (4) , Tayssir Hamieh (1, 5) , Daniela Cordella , Christophe Detrembleur (6) , Jean-Pierre Fouassier (1) , Jacques Lalevée (1)

1 IS2M - Institut de Science des Matériaux de Mulhouse
2 ISCR - Institut des Sciences Chimiques de Rennes
3 ICR - Institut de Chimie Radicalaire
4 MCEMA - Laboratoire de Matériaux, Catalyse, Environnement et Méthodes Analytiques
5 MCEMA - Laboratoire de Matériaux, Catalyse, Environnement et Méthodes Analytiques
6 CERM - Centre d'Etude et de Recherche sur les Macromolécules

A novel photoinitiator based on a spiroxanthene scaffold in the presence of an iodonium salt is proposed for the cationic ring-opening polymerization of a diepoxide, as well as for the free-radical polymerization of an acrylate upon violet LED exposure (385 and 405 nm). Good-to-excellent rates of polymerization and final conversions are obtained. These systems are characterized by a higher reactivity compared with that of anthracene/iodonium salt used as reference for cationic near UV polymerization. The addition of a poly(ionic liquid) improves the cationic polymerization profiles. The photochemical mechanisms are studied by steady-state photolysis, fluorescence, and electron spin resonance spin-trapping techniques. Molecular orbital calculations give an insight into the light absorption properties. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43213

Mots clés: Photochemistry; irradiation; radical polymerization; photopolymerization

Domaines: Chimie

Haifaa Mokbel, Cyril Poriel, Joëlle Rault-Berthelot, Frédéric Dumur, Didier Gigmes, et al.. A glance at violet LED sensitive photoinitiators based on the spiroxanthene scaffold. Journal of Applied Polymer Science, 2016, 133 (12), ⟨10.1002/app.43213⟩. ⟨hal-01240653⟩