Cationic Photopolymerization Kinetics of a Cycloaliphatic Diepoxide Using a Ferrocenium System Under UV-LED Exposure

doi:10.7517/issn.1674-0475.190922

Abstract

Abstract: Cationic photopolymerization kinetics of cycloaliphatic diepoxide (CE) has been investigated by real-time Fourier transform infrared spectroscopy (real time FTIR) under UV-LED light (405 nm),using cyclopentadien-Fe-cymene hexafluorophosphate (I-261) as an initiator and using 2-isopropyl-9H-thioxanthen-9-one (ITX), curcumin (CC), and 1-[4-(phenylazo)phenyl]azo]-2-naphthaleno (Sudan Ⅲ) as the photosensitizers. The enhancing monomer conversion rate and polymerization rate of CE was achieved by complex initiator with photosensitizers. All photosensitizers were effective in initiating the photopolymerization while ITX and CC exhibited higher efficiency during the photopolymerization. As a result, with 8.0%(mass fraction) I-261 and 0.5% ITX, the monomer conversion of CE has reached to more than 89% from 74.4%,the maximum polymerization rate increased to 1.9 times. Moreover, using 8.0% (mass fraction) I-261 and 1.0% CC, the monomer conversion of CE has reached to more than 88% from 74.4%,the maximum polymerization rate increased to 1.7 times for the epoxy system.

Key words: cationic photopolymerization, UV-LED, cycloaliphatic epoxy monomer

GAO Yang, SU Jiahui, LIU Xiaoxuan. Cationic Photopolymerization Kinetics of a Cycloaliphatic Diepoxide Using a Ferrocenium System Under UV-LED Exposure[J]. Imaging Science and Photochemistry, 2020, 38(2): 190-199.

References

[1] Xiao P, Zhang J, Dumur F, et al. Visible light sensitive photoinitiating systems:recent progress in cationic and radical photopolymerization reactions under soft conditions[J]. Progress in Polymer Science, 2015,41:32-66.
[2] Dadashi-Silab S, Doran S, Yagci Y. Photoinduced electron transfer reactions for macromolecular syntheses[J]. Chemical Reviews, 2016,116(17):10212-10275.
[3] Yeow J, Boyer C. Photoinitiated polymerization-induced self-assembly (photo-PISA):new insights and opportunities[J]. Advanced Science, 2017,4(7):1700137.
[4] Lalevée J, Mokbel H, Fouassier J P. Recent developments of versatile photoinitiating systems for cationic ring opening polymerization operating at any wavelengths and under low light intensity sources[J]. Molecules, 2015,20(4):7201-7221.
[5] Sun X, Jin M, Wu X Y, et al. Bis-substituted thiophene-containing oxime sulfonates photoacid generators for cationic polymerization under UV-visible LED irradiation[J]. Journal of Polymer Science Part A:Polymer Chemistry, 2018,56(7):776-782.
[6] Schissel S M, Jessop J L P. Controlling shadow cure in cationic photopolymerizations using physical cues and processing variables[J]. Journal of Applied Polymer Science, 2019:48290.
[7] Li B, Hou W, Sun J, et al. Tunable functionalization of graphene oxide sheets through surface-initiated cationic polymerization[J]. Macromolecules, 2015,48(4):994-1001.
[8] Crivello J V, Lam J H W. Diaryliodonium salts. A new class of photoinitiators for cationic polymerization[J]. Macromolecules, 1977,10(6):1307-1315.
[9] Crivello J V, Lam J H W. Photoinitiated cationic polymerization by dialkyl-4-hydroxyphenylsulfonium salts[J]. Journal of Polymer Science:Polymer Chemistry Edition, 1980,18(3):1021-1034.
[10] Jin M, Zhou R, Yu M, et al. D-π-a-type oxime sulfonate photoacid generators for cationic polymerization under UV-visible LED irradiation[J]. Journal of Polymer Science Part A:Polymer Chemistry, 2018,56(11):1146-1154.
[11] Li M, Chen Y, Zhang H Q, et al. A novel ferrocenium salt as visible light photoinitiator for cationic and radical photopolymerization[J]. Progress in Organic Coatings, 2010,68(3):234-239.
[12] Xiao P, Zhang J, Campolo D, et al. Copper and iron complexes as visible-light-sensitive photoinitiators of polymerization[J]. Journal of Polymer Science Part A:Polymer Chemistry, 2015,53(23):2673-2684.
[13] Ciftci M, Kork S, Xu G, et al. Polyethylene-g-poly (cyclohexene oxide) by mechanistic transformation from romp to visible light-induced free radical promoted cationic polymerization[J]. Macromolecules, 2015,48(6):1658-1663.
[14] Zhang J, Dumur F, Xiao P, et al. Structure design of naphthalimide derivatives:Toward versatile photoinitiators for near-UV/visible LEDs, 3D printing, and water-soluble photoinitiating systems[J]. Macromolecules, 2015,48(7):2054-2063.
[15] Shi S Q, Croutxe-Barghorn C, Allonas X. Photoinitiating systems for cationic photopolymerization:ongoing push toward long wavelengths and low light intensities[J]. Progress in Polymer Science, 2017,65:1-41.
[16] Wang T, Chen J W, Li Z Q, et al. Several ferrocenium salts as efficient photoinitiators and thermal initiators for cationic epoxy polymerization[J].Journal of Photochemistry & Photobiology A:Chemistry, 2007,187(2):389-394.
[17] Zhang J, Campolo D, Dumur F, et al. The carbazole-bound ferrocenium salt as a specific cationic photoinitiator upon near-UV and visible LEDs (365-405 nm)[J]. Polymer Bulletin, 2016,73(2):493-507.
[18] Chen Y, Jia X Q, Wang M Q, et al. A synergistic effect of a ferrocenium salt on the diaryliodonium salt-induced visible-light curing of bisphenol-A epoxy resin[J]. RSC Advances, 2015,5(42):33171-33176.
[19] Li M, Chen Y, Zhang H Q, et al. A novel ferrocenium salt as visible light photoinitiator for cationic and radical photopolymerization[J]. Progress in Organic Coatings, 2010,68(3):234-239.
[20] Li Z Q, Li M, Li G L, et al. Naphthoxy bounded ferrocenium salts as cationic photoinitiators for epoxy photopolymerization[J]. International Journal of Photoenergy, 2009,2009:981065.
[21] Chen Y, Jin S, Liu J Q, et al. Photo-Fenton reaction of supported cationic cyclopentadienyl iron complexes of arene and application as heterogeneous catalysts in photodegradation of dyes under visible light[J]. Inorganica Chimica Acta, 2013,406:37-43.
[22] Fouassier J P, Lalevée J. Three-component photoinitiating systems:towards innovative tailor made high performance combinations[J]. RSC Advances, 2012,2(7):2621-2629.
[23] Corcione C E, Malucelli G, Frigione M, et al. UV-curable epoxy systems containing hyperbranched polymers:Kinetics investigation by photo-DSC and real-time FT-IR experiments[J]. Polymer Testing, 2009,28(2):157-164.
[24] Sangermano M, Malucelli G, Bongiovanni R, et al. Coatings obtained through cationic UV curing of epoxide systems in the presence of epoxy functionalized polybutadiene[J].Journal of Materials Science, 2002,37(22):4753-4757.
[25] Zheng K, Zhu X Q, Qian X C, et al. Cationic photopolymerization of 3-benzyloxymethyl-3-ethyl-oxetane[J]. Polymer International, 2016,65(12):1486-1492.
[26] 刘晓暄,廖正福,崔艳艳,等.高分子光化学原理与光固化技术[M]. 北京:科学出版社, 2019.215-216. Liu X X, Liao Z F, Cui Y Y, et al. Polymer Photochemical Principle and Photocuring Technology[M]. Beijing:Science Press, 2019. 215-216.