Akademik Veri Yönetim Sistemi
7th European Symposium of Photopolymer Science, İstanbul, Türkiye, 19 - 22 Eylül 2022, ss.60
The design of new photoinitiators for photoinitiated free radical, cationic and free radical promoted cationic reactions has received a considerable attention over the past decade due to their curicial role in the polymerization process. New developments in photopolymerization systems contribute to economic and environmental factors, offering advantages such as rapid recovery, low energy requirements and solvent-free formulations [1, 2]. Therefore, the photoinitiators which are able to initiate to the photoinitiated polymerization reaction under visible light are especially importance for everyday. In this way, many researchers focuse on (i) the design of new structures and (ii) modification of excisting structures to develop new photoinitiaters operating using UV or visible light. It is known that the structural changes in excisting classes of photoinitiators allow a real red-shift of the absorption and/ or an icrease of the molar absorption efficiency [3, 4]. In this study, we introduce to the literature thioxanthone-coumarin (TX-Coum) as a new photoinitiator molecule by revealing a bifunctional structure involving both thioxanthone and coumarin molecules. With the appropriate molecular design of the thioxantone molecule with chemically containing coumarin structure, it would be provided to the promient light absorption properties near and/ or in the visible spectral region in order to develop a new visible photoinitiator for polymer science. Then, the photophysical and photochemical properties of TX-Coum in the singlet and the triplet excited states were investigated by using fluorescence and phosphorescence spectroscopies.
Keywords: photoinitiator, photopolymerization, thioxanthone, coumarin