A Quinoxaline Derivative as a Long Wavelength Photosensitizer for Diaryliodonium Salts

This article reports the use of a quinoxaline derivative as a photosensitizer for diaryliodonium salt photoinitiators. 2,3-bis(3,4-bis(decyloxy)phenyl)-5,8-bis(2,3-dihydrothieno[3,4-b][1,4]-dioxin-5-yl)quinoxaline (DOPEQ), is a highly conjugated compound with strong absorption bands at wavelengths ranging from 300 to 550 nm and is shown to facilitate photoinitiated cationic polymerization of heterocyclic monomers such as oxiranes and oxetanes. The polymerizations are initiated at room temperature by using long wavelength UV light in the presence of diphenyliodonium hexafluorophosphate (Ph2I+PF6-). The polymerizations are monitored by optical pyrometry (OP). It is also possible to initiate photopolymerizations with ambient solar irradiation in the presence of this photosensitizer dye. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 209-213, 2010