title: Fluorescent Brighteners as Visible LED-Light Sensitive Photoinitiators for Free Radical Photopolymerizations.
abstract: The photochemical and electrochemical investigations of commercially available, safe, and cheap fluorescent brighteners, namely, triazinylstilbene (commercial name: fluorescent brightener 28) and 2,5-bis(5-tert-butyl-benzoxazol-2-yl)thiophene, as well as their original use as photoinitiators of polymerization upon light emitting diode (LED) irradiation are reported. Remarkably, their excellent near-UV-visible absorption properties combined with outstanding fluorescent properties allow them to act as high-performance photoinitiators when used in combination with diaryliodonium salt. These two-component photoinitiating systems can be employed for free radical polymerizations of acrylate. In addition, this brightener-initiated photopolymerization is able to overcome oxygen inhibition even upon irradiation with low LED light intensity. The underlying photochemical mechanisms are investigated by electron-spin resonance-spin trapping, fluorescence, cyclic voltammetry, and steady-state photolysis techniques.
authors.affiliation: Institut de Science des Materiaux de Mulhouse IS2M, UMR CNRS 7361, UHA, 15, Rue Jean Starcky, 68057, Mulhouse Cedex, France.|Laboratoire de Chimie Organique et Bioorganique, EA4566, UHA, ENSCMu, 3 rue Alfred Werner, 68093, Mulhouse Cedex, France.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Zuo
authors.affiliation: Institut de Science des Materiaux de Mulhouse IS2M, UMR CNRS 7361, UHA, 15, Rue Jean Starcky, 68057, Mulhouse Cedex, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Morlet-Savary
authors.affiliation: Institut de Science des Materiaux de Mulhouse IS2M, UMR CNRS 7361, UHA, 15, Rue Jean Starcky, 68057, Mulhouse Cedex, France.
authors.forename: Bernadette
authors.initials: B
authors.lastname: Graff
authors.affiliation: Laboratoire de Chimie Moléculaire, Université de Strasbourg, UMR CNRS 7509, ECPM, 25 rue Becquerel, 67087, Strasbourg, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Blanchard
authors.affiliation: Laboratoire de Chimie Organique et Bioorganique, EA4566, UHA, ENSCMu, 3 rue Alfred Werner, 68093, Mulhouse Cedex, France.
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Goddard
authors.affiliation: Institut de Science des Materiaux de Mulhouse IS2M, UMR CNRS 7361, UHA, 15, Rue Jean Starcky, 68057, Mulhouse Cedex, France.
authors.forename: Jacques
authors.initials: J
authors.lastname: Lalevée
mesh_terms: D001557:Benzenesulfonates / Q000737:chemistry; D001583:Benzoxazoles / Q000737:chemistry; D005453:Fluorescence; D005609:Free Radicals / Q000737:chemistry*; D008027:Light; D010777:Photochemistry; D058105:Polymerization; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D013876:Thiophenes / Q000737:chemistry
chemical_list: C000614082:2,5-bis(5-tert-butylbenzoxazol-2-yl)thiophene; D001557:Benzenesulfonates; D001583:Benzoxazoles; D005609:Free Radicals; D011108:Polymers; D013876:Thiophenes; C007061:C.I. Fluorescent Brightening Agent 28
keywords: fluorescent brighteners; free radical photopolymerization; light emitting diode (LED); photoinitiator