Photophysical/Photochemical, Kinetic, and Migration Stability Studies of One‐Component Polymerizable Thioxanthone‐Based Photoinitiators

Abstract

Herein, N‐benzyl‐N‐(9‐oxo‐9H‐thioxanthen‐2‐yl)acrylamide (TXNBA) is designed and synthesized as one‐component polymerizable photoinitiator (PI). It is investigated in terms of its photophysical/photochemical, kinetic, and migration stability properties by ultraviolet‐visible spectrophotometer, Fourier transform infrared spectrometer, and EPR spin trapping experiments. In conjunction with the experimental studies, series of density functional theory calculations are performed and various photophysical and photochemical properties are computationally calculated and visualized. The photolysis and photoinitiation mechanism of TXNBA is clarified. Comparison of the results of 2‐isopropylthioxanthone (ITX) system has shown that TXNBA is an efficient one‐component polymerizable PI with excellent migration stability. The photoinitiator's migration ratio of TXNBA system to ITX system is 8.52%.

N‐(9‐Oxo‐9H‐thioxanthen‐2‐yl) acrylamide as a Versatile Photoinitiator for Photopolymerization

“…Kreutzer et al [16] reported two Schiff base PIs (TX-EDA and TX-DETA) could initiate FRP. In our previous work, the polymerizable PIs, such as 4-((methyl(9-oxo-9H-thioxanthen-2yl)amino)methyl)phenyl acrylate (TX-PA), [17] ((4-((methyl(9-oxo-9H-thioxanthen-2-yl)amino)methyl)benzyl)-azanediyl) bis(ethane-2,1-diyl) diacrylate (TX-BDA), [18] and N-benzyl-N-(9oxo-9H-thioxanthen-2-yl)acrylamide (TXNBA) [19] were studied with efficient photoinitiated properties and high migration stability. We are dedicated to looking for efficient PIs that are simpler to synthesize and have better storage stability.…”