Synthesis and Photochemical Properties of Photobase Generators Containing Thioxanthone

doi:10.7517/j.issn.1674-0475.2017.01.070

Abstract

Abstract:

A novel photobase generator (PBG) was synthesized in two steps using thiosalicylic acid and (phenylthio)acetic acid as starting materials. The structure of the PBG was characterized by ¹HNMR, ¹³CNMR and high-resolution mass spectrometer. The photolysis mechanism was systematically studied via steady photolysis and electron spin resonance tests. The PBG showed a strong absorption at around 400 nm. Under the 365~500 nm irradiation, the PBG could efficiently induce thiol-epoxy photopolymerization. The initiation efficiency of the PBG was higher than that of the reported efficient PBG initiation system in the literature.

Key words: photobase generator, photoinduced decarboxylation, thiol-epoxy photopolymerization, photocuring

SHEN Weizhen, LIU Xiaoya, LIU Ren, LI Zhiquan. Synthesis and Photochemical Properties of Photobase Generators Containing Thioxanthone[J]. Imaging Science and Photochemistry, 2017, 35(1): 70-79.

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