Long wavelength photosensitizers in photoinitiated cationic polymerization: The effect of quinoxaline derivatives on photopolymerization

This article describes the use of functionalized quinoxaline derivatives as photosensitizers for diaryliodonium salt photoinitiators. Highly conjugated compounds with good absorption bands in long wavelength UV and visible region are presented. These versatile intermediates facilitate photoinitiated cationic polymerization of commercially important monomers such as cyclic ethers and vinyl epoxides. Polymerizations were carried out using long wavelength UV light in the presence of diphenyliodonium hexafluorophosphate (Ph2I+PF6-). The polymerizations were monitored by optical pyrometry (OP). In addition, we also demonstrate that it was also possible to initiate photopolymerizations under solar irradiation in the presence of these photosensitizers. (c) 2013 Elsevier Ltd. All rights reserved.