A novel bifunctional photoinitiator (named as TX-EG-IPDI-2959) with thioxanthone and hydroxyalkylphenone moieties was synthesized by the reaction of isophorone diisocyanate with Irgacure 2959 and 2-(2-hydroxyethoxy) thioxanthone. The molecular structure of TX-EG-IPDI-2959 was characterized by ¹H NMR, high-resolution mass spectroscopy, UV–vis and FT-IR. The photochemical behavior of TX-EG-IPDI-2959 was investigated through the photolysis and polymerization of butyl acrylate by UV–vis and HRMS. Compared with the combination of Irgacure 2959 and 2-(2-hydroxyethoxy) thioxanthone, the CC bond cleavage of hydroxyalkylphenone to produce free radical fragments was effectively done under the irradiation of visible LED light. The obvious intramolecular synergistic effect between the hydroxyalkylphenone and thioxanthone moieties has been confirmed based on HRMS analysis of photobleach and photopolymerization. In addition, the photopolymerization kinetic of an UV gel and trimethylolpropane triacrylate initiated by TX-EG-IPDI-2959 were also investigated. The plausible photochemical reaction mechanism of TX-EG-IPDI-2959 was proposed.

通过异佛尔酮二异氰酸酯与Irgacure 2959和2-（2-羟基乙氧基）噻吨酮的反应，合成了具有噻吨酮和羟烷基苯酮部分的新型双功能光引发剂（命名为TX-EG-IPDI-2959）。TX-EG-IPDI-2959的分子结构通过¹ H NMR，高分辨率质谱，UV-vis和FT-IR进行表征。通过UV-vis和HRMS对丙烯酸丁酯的光解和聚合反应，研究了TX-EG-IPDI-2959的光化学行为。与Irgacure 2959和2-（2-羟基乙氧基）噻吨酮的组合相比，C在可见光的照射下有效地完成了羟烷基苯甲酮的C键裂解以产生自由基片段。基于光漂白和光聚合的HRMS分析，已经证实了羟烷基苯酮和噻吨酮部分之间的明显的分子内协同作用。另外，还研究了由TX-EG-IPDI-2959引发的UV凝胶和三羟甲基丙烷三丙烯酸酯的光聚合动力学。提出了TX-EG-IPDI-2959可能的光化学反应机理。