香豆素肟酯类双光子引发剂的合成及性能研究

doi:10.7517/issn.1674-0475.190603

摘要/Abstract

摘要： 开发高效的双光子引发剂是提升双光子聚合速度的关键。本文基于光致脱羧机制，设计并合成了两种以共轭香豆素作为生色团、肟酯作为引发基团的双光子引发剂，并通过实验测试结合模拟计算对该类引发剂的光物理和光化学行为进行了研究。结果表明，该类引发剂在400~500 nm区域具有较强吸收，在LED可见光辐照下发生分解，具有光漂白特性，光解后释放的活性种可引发丙烯酸酯类单体聚合。利用双光子三维微纳成型技术，该类香豆素肟酯化合物可有效用于构建高分辨率的三维微纳结构。并通过量子化学计算，对该类引发剂的引发机理进行了探讨。

关键词: 光引发剂, 双光子聚合, 光致脱羧, 肟酯, 香豆素

Abstract: Development of efficient two-photon initiators (2PIs) are critical to promote two-photon 3D printing speeds. On the basis of photodecarboxylation, two unimolecular 2PIs that contain coumarin moieties (as two-photon absorption chromophores) and oxime-ester groups (as initiation functional groups) were synthesized. The investigation of the photophysical and photochemical behaviors of the oxime-esters were conducted via quantum-chemical calculations and experimental tests. The results indicated that the 2PIs exhibits a broad absorption band ranging from 400 to 500 nm. Under visible LED light irradiation, the investigated oxime-esters decomposed and formed active free radicals to effectively induce polymerization of acrylates. Interestingly, the photoinitiators exhibit a good photobleaching property. In two-photon polymerization tests with acrylate formulations, the oxime-ester derivatives can be used to build complex 3D microstructures with high spatial resolution. The possible photopolymerization mechanism was proposed according to the quantum chemical calculation results.

Key words: photoinitiators, two-photon polymerization, photodecarboxylation, oxime-esters, coumarin

李梦琦, 邱婉婉, 胡鹏, 朱俊哲, 刘仁, 李治全. 香豆素肟酯类双光子引发剂的合成及性能研究[J]. 影像科学与光化学, 2019, 37(5): 415-427.

LI Mengqi, QIU Wanwan, HU Peng, ZHU Junzhe, LIU Ren, LI Zhiquan. Synthesis and Structure-activity Relationship of Coumarin-based Oxime-esters as Two-photon Photoinitiators[J]. Imaging Science and Photochemistry, 2019, 37(5): 415-427.

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