Gao Tong, Zhang Yijun, Morlet-Savary Fabrice, Graff Bernadette, Zhang Jing, Xiao Pu, Dumur Frédéric, Lalevée Jacques
Université de Haute-Alsace, CNRS, IS2M UMR7361, Mulhouse, F-68100, France.
Université de Strasbourg, France.
Small. 2024 Jul;20(29):e2400234. doi: 10.1002/smll.202400234. Epub 2024 Mar 1.
Investigations concerning the glyoxylate moiety as a photocleavable functional group for visible light photoinitiators, particularly in the initiation of free radical photopolymerization remain limited. This study introduces nine innovative carbazole-based ethyl glyoxylate derivatives (CEGs), which are synthesized and found to exhibit excellent photoinitiation abilities as monocomponent photoinitiating systems. Notably, these structures demonstrate robust absorption in the near-UV/visible range, surpassing the commercial photoinitiators. Moreover, the newly developed glyoxylate derivatives show higher acrylate function conversions compared to a benchmark photoinitiator (MBF) in free radical photopolymerization. Elucidation of the photoinitiation mechanism of CEGs is achieved through a comprehensive analysis involving the decarboxylation reaction and electron spin resonance spin trapping. Furthermore, their practical utility is confirmed during direct laser writing and 3D printing processes, enabling the successful fabrication of 3D printed objects. This study introduces pioneering concepts and effective strategies in the molecular design of novel photoinitiators, showcasing their potential for highly advantageous applications in 3D printing.
关于乙醛酸部分作为可见光光引发剂的可光裂解官能团的研究，特别是在自由基光聚合引发方面仍然有限。本研究介绍了九种创新的基于咔唑的乙醛酸乙酯衍生物（CEG），它们被合成并发现作为单组分光引发体系表现出优异的光引发能力。值得注意的是，这些结构在近紫外/可见光范围内表现出强烈的吸收，超过了商业光引发剂。此外，新开发的乙醛酸衍生物在自由基光聚合中比基准光引发剂（MBF）表现出更高的丙烯酸酯官能团转化率。通过涉及脱羧反应和电子自旋共振自旋捕获的综合分析，阐明了CEG的光引发机理。此外，它们在直接激光写入和3D打印过程中的实际效用得到了证实，能够成功制造3D打印物体。本研究在新型光引发剂的分子设计中引入了开创性的概念和有效策略，展示了它们在3D打印中极具优势的应用潜力。
