Synthesis and Photochemical Properties of One-component Visible-light Photoinitiator Based on Photodecarboxylation

doi:10.7517/j.issn.1674-0475.2018.03.003

Abstract

Abstract: One-component visible-light photoinitiators receive more attention recently. A novel photoinitiator-tetraphenylphosphonium 2-(9-oxo-9H-thioxanthen-2-yl)acetate(TXP) was synthesized and contained thioxanthone as the chromophore, which generate radicals via photodecarboxylation reaction. The structure was characterized by ¹HNMR, ¹³CNMR and HR-MS. The study on photolysis confirmed the photoinduced decarboxylation mechanism. The novel photoinitiator showed high activity in initiating thiol-ene click polymerization under visible-light LED sources, which makes the photoinitiator promising candidates for one-component visible-light photoinitiator.

Key words: photoinitiator, one-component, photodecarboxylation, photopolymerization, tetraphenylphosphonium 2-(9-oxo-9H-thioxanthen-2-yl)acetate(TXP)

DONG Xiaoqing, LI Zhiquan, LIU Ren, LIU Xiaoya. Synthesis and Photochemical Properties of One-component Visible-light Photoinitiator Based on Photodecarboxylation[J]. Imaging Science and Photochemistry, 2018, 36(3): 226-235.

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