香豆素基脂环族肟酯可见光引发剂的合成及性能研究

doi:10.7517/issn.1674-0475.220205

摘要/Abstract

摘要： 本文设计并合成了一系列以香豆素为生色团、肟酯为引发基团的可见光引发剂。通过在肟酯末端引入不同结构的脂肪环，探究了脂肪环自由基作为活性种引发光聚合的行为。该类肟酯光引发剂在350～500 nm具有良好的吸收，在LED可见光辐照下迅速发生光解，具有光漂白特性，光解后产生的活性种可有效引发丙烯酸酯类单体和巯-烯体系单体的自由基光聚合，并可进一步应用于DLP 3D打印，构筑精度较高的三维发光结构。

关键词: 可见光引发剂, 脂肪环自由基, 肟酯, 香豆素

Abstract: A series of visible light photoinitiators, containing coumarins as chromophores and oxime-esters as initiating groups, were designed and synthesized. The alicyclic groups with different structures were introduced at the end of the oxime esters to study the behavior of alicyclic radicals as active species. The oxime-ester photoinitiators show strong absorption at 350-500 nm and rapid photolysis occurs under LED visible light irradiation with photobleaching characteristics. The active species generated after photolysis can effectively initiate free radical photopolymerization of acrylate monomers and thiol-ene monomers. The novel photoinitiators can be further applied to DLP 3D printing to construct luminescent 3D structures with high precision.

Key words: visible light photoinitiator, alicyclic free radical, oxime ester, coumarin

李梦琦, 朱俊哲, 胡鹏, 李治全, 刘仁. 香豆素基脂环族肟酯可见光引发剂的合成及性能研究[J]. 影像科学与光化学, 2022, 40(4): 704-713.

LI Mengqi, ZHU Junzhe, HU Peng, LI Zhiquan, LIU Ren. Synthesis and Properties of Coumarin-based Alicyclic Oxime-esters as Visible Light Photoinitiators[J]. IMAGING SCIENCE AND PHOTOCHEMISTRY, 2022, 40(4): 704-713.

参考文献

[1] Yagci Y, Jockusch S, Turro N J. Photoinitiated polymerization:Advances, Challenges, and Opportunities[J]. Macromolecules, 2010,43(15):6245-6260.
[2] Corrigan N, Yeow J, Judzewitsch P, et al. Seeing the light:Advancing materials chemistry through photopolymeriza-tion[J]. Angewandte Chemie International Edition, 2019,58(16):5170-5189.
[3] Batibay G S, Gunkara O T, Ocal N, et al. Thioxanthone attached polyhedral oligomeric silsesquioxane (POSS) Nano-Photoinitiator for Preparation of PMMA Hybrid Networks in Air Atmosphere[J]. Progress in Organic Coatings, 2020,149:105939-105946.
[4] Petko F, Galek M, Hola E, et al. One-Component cationic photoinitiators from tunable benzylidene scaffolds for 3D printing applications[J]. Macromolecules, 2021,54(15):7070-7087.
[5] Dietliker K, Hüsler R, Birbaum J-L, et al. Advancements in photoinitiators-opening up new applications for radiation curing[J]. Progress in Organic Coatings, 2007,58(2-3):146-157.
[6] Groenenboom C J, Hageman H J, Oosterhoff P, et al. Photoinitiators and photoinitiation part 11. the photodecomposition of some O-Acyl 2-Oximinoketones[J]. Journal of Photochemistry and Photobiology A:Chemistry, 1997,107(1-3):261-269.
[7] Mallavia R, Sastre R, Amat-Guerri F. Photofragmentation and photoisomerization of O-acyl-α-oxooximes:Quantum yields and mechanism[J]. Journal of Photochemistry and Photobiology A:Chemistry, 2001,138(3):193-201.
[8] Qiu W W, Hu P, Zhu J Z, et al. Cleavable unimolecular photoinitiators based on oxime-ester chemistry for two-photon three-dimensional printing[J]. ChemPhotoChem, 2019,3(11):1090-1094.
[9] Guo X Y, Wang W J, Wan D C, et al. Substituted stilbene-based d-π-a and a-π-a type oxime esters as photoinitiators for led photopolymerization[J]. European Polymer Journal, 2021,156:110617-110628.
[10] Fast D E, Lauer A, Menzel J P, et al. Wavelength-dependent photochemistry of oxime ester photoinitiators[J]. Macromolecules, 2017,50(5):1815-1823.
[11] Muramatsu Y, Kaji M, Unno A, et al. Terminal group analyses of photopolymerized products using a MALDI-TOFMS for the study on the oxime ester type photoinitiators[J]. Journal of Photopolymer Science and Technology, 2010,23(3):447-450.
[12] Xu J, Ma G P, Wang K M, et al. Synthesis and photopolymerization kinetics of oxime ester photoinitiators[J]. Journal of Applied Polymer Science, 2012,123(2):725-731.
[13] Li Z Q, Zou X C, Zhu G G, et al. Coumarin-based oxime esters:photobleachable and versatile unimolecular initiators for acrylate and thiol-based click photopolymerization under visible light-emitting diode light irradiation[J]. ACS Applied Materials & Interfaces, 2018,10(18):16113-16123.
[14] Eibel A, Fast D E, Sattelkow J, et al. Star-shaped polymers through simple wavelength-selective free-radical photopolymerization[J]. Angewandte Chemie International Edition, 2017,56(45):14306-14309.
[15] Ding Y Y, Jiang S L, Gao Y J, et al. Photochromic polymers based on fluorophenyl oxime ester photoinitiators as photoswitchable molecules[J]. Macromolecules, 2020,53(14):5701-5710.
[16] Qiu W W, Li M Q, Yang Y N, et al. Cleavable coumarin-based oxime esters with terminal heterocyclic moieties:photobleachable initiators for deep photocuring under visible led light irradiation[J]. Polymer Chemistry, 2020,11(7):1356-1363.
[17] Corvaja C, Brustolon M, Giacometti G. ESR spectra and conformations of alicyclic free radicals produced in redox systems[J]. Zeitschrift für Physikalische Chemie, 1969,66(4-6):279-292.
[18] Johnston L J, Scaiano J C, Ingold K U. Kinetics of cyclopropyl radical reactions. 1. absolute rate constants for some addition and abstraction reactions[J]. Journal of the American Chemical Society, 1984,106(17):4877-4881.
[19] Zhao Y, Truhlar D G. The M06 suite of density functionals for main group thermochemistry, thermochemical kinetics, noncovalent interactions, excited states, and transition elements:Two new functionals and systematic testing of four m06-class functionals and 12 other functionals[J]. Theoretical Chemistry Accounts, 2008,120(1-3):215-241.
[20] Pritchard B P, Altarawy D, Didier B, et al. New basis set exchange:An open, Up-to-Date resource for the molecular sciences community[J]. Journal of Chemical Information and Modeling, 2019,59(11):4814-4820.
[21] Dumur F. Recent Advances on Coumarin-Based photoinitiators of polymerization[J]. European Polymer Journal, 2022,163:110962-110996.
[22] Liu M, Han J W, Yan C X, et al. Photocontrollable release with coumarin-based profragrances[J]. ACS Applied Bio Materials, 2019,2(9):4002-4009.
[23] Liu M, Yan C X, Han J W, et al. Engineering photo-controllable fragrance release with flash nanoprecipitation[J]. Green Chemical Engineering, 2021,2(3):301-308.
[24] Hoyle C E, Lowe A B, Bowman C N. Thiol-Click chemistry:A multifaceted toolbox for small molecule and polymer synthesis[J]. Chemical Society Reviews, 2010,39(4):1355-1387.
[25] Zhao Z, Tian X X, Song X Y. Engineering materials with light:recent progress in digital light processing based 3d printing[J]. Journal of Materials Chemistry C, 2020,8(40):13896-13917.
[26] Qiu W W, Zhu J Z, Dietliker K, et al. Polymerizable oxime esters:An efficient photoinitiator with low migration ability for 3d printing to fabricate luminescent devices[J]. ChemPhotoChem, 2020,4(11):5296-5303.