Novel polymeric photoinitiators comprising of side-chain benzophenone and coinitiator amine: Photochemical and photopolymerization behaviors

Three kinds of macrophotoinitiators, PBP-P, PBP-E and PBP-B, were synthesized by step-polymerization of benzophenone and different coinitiator amino monomers. The low molecular weight analogue, 2,4-di(3-(diethyl amino)-2-hydroxypropoxy)-benzophenone (DAHBP), was also synthesized as a low molecular weight model compound. The UV-vis spectra of PBP-P, PBP-E, PBP-B and DAHBP are similar with large red-shifted maximum absorption comparing with BP. ESR spectra of PBP-P and DAHBP possess the same initiation mechanism with DEBP/TEA systems. The photopolymerization of two monomers with different functionality poly(propylene glycol)diacrylate (PPGDA) and trimethylolpropane triacrylate (TMPTA), initiated by macrophotoinitiators and low molecular weight analogs, was studied through photo-DSC. The results show that different efficiency of photoinitiators towards monomers: first, polymeric photoinitiators are more efficient than low molecular weight analogs; then PBP-E is the most efficient for PPGDA; lastly, PBP-B is the most efficient for TMPTA. The efficiency of the photopolymerization is mainly affected by structure of amine in macrophotoinitiator.     

吸光度与光聚合动力学

光聚合中许多动力学“反常”现象可以用吸光度的影响来解释。体系吸光度受引发剂浓度、消光系数、体系厚度和入射光波长的影响,因此,这四个因素都会影响光聚合动力学。体系低吸光度时光聚合动力学与热聚合时类似,而在高吸光度时完全不同。     

Photoinitiating Characteristics of Benzophenone Derivatives as Type II Macromolecular Photoinitiators Used for UV Curable Resins

Dodecyl-benzophenone(DBP) and hexadecoxyl-benzophenone(HDBP) as type II photoinitiators used for radical photopolymerization systems were synthesized by Friedel-Crafts reaction, and characterized by 1H NMR and FTIR spectroscopy. The UV-Vis absorption spectra of DBP and HDBP, propitious to photopolymerization under a commercial mercury UV bulb are centered at 345 and 335 nm, respectively. HDBP has higher extinction coefficient than DBP, but lower photoinitiating efficiency. Their photoinitiating performances...     

大分子量二苯甲酮光引发剂的合成及动力学研究

以4-羟基二苯甲酮(HBP)、甲苯-2,4-二异氰酸酯(TDI)、4,4′-二羟基二苯甲酮(DHBP)为原料,通过两步反应,合成了一种大分子量二苯甲酮光引发剂:HBP-TDI-DHBP-TDI-HBP(HTDTH).通过实时红外研究了HTDTH的光聚合动力学.结果表明,HTDTH是一种有效的光引发剂.采用HTDTH/胺光引发体系引发二缩三丙二醇二丙烯酸酯(TPGDA)聚合时,随着胺和引发剂浓度的增大,反应速率(R_p)和单体最终转化率(P)同时增大.     

One‐component photoinitiator based on benzophenone and sesamol

A new benzodioxole derivative, 4‐(1,3‐benzodioxol‐5‐yloxy) benzophenone (BPBDO), based on benzophenone and sesamol was precisely synthesized, and it can be used as a 1‐component type II photoinitiator. Elementary analysis, atmospheric pressure chemical ionization mass spectrometry, ¹H nuclear magnetic resonance, and ¹³C nuclear magnetic resonance studies revealed that the molecular structure of BPBDO consisted of both benzophenone (BP) and benzodioxole (BDO) structures. The laser flash photolysis experiments and electron spin resonance test indicated that the process of radicals generated from BPBDO after irradiation was similar to 3 processes of ethyl 4‐dimethylaminobenzoate and BP. The kinetics of photopolymerization of the photoinitiator was also studied by real‐time infrared spectroscopy. The oxygen content, light intensity, and viscosity of the monomer affected the decomposition (R_d) and polymerization rate, and the final double bond conversion was also studied. All the results suggest that BPBDO is a 1‐component photoinitiator that is an efficient photoinitiator for free radical polymerization. In contrast to typical dual‐component photoinitiators, eg, BP/ethyl 4‐dimethylaminobenzoate or BP/BDO, BPBDO does not require an additional amine coinitiator for the initiation and is applicable in nonamine resin systems.     

Novel,highly efficient polymeric benzophenone photoinitiator containing coinitiator moieties for photopolymerization

A novel polymeric photoinitiator P(MPBP‐co‐DMAEMA), bearing side‐chain benzophenone (BP) and coinitiator amine, was synthesized through free radical copolymerization of a polymerizable photoinitiator, 4‐[(4‐maleimido)phenoxy]benzophenone (MPBP), and a polymerizable coinitiator amine, N, N‐dimethylaminoethyl methacrylate (DMAEMA). In order to find out the influences of coinitiator amine on photopolymerization, a polymeric coinitiator amine, P(DMAEMA), was also synthesized for comparison. FT‐IR, ¹H NMR, and GPC analyses confirm the structures of polymers. The UV‐Vis spectra of polymeric photoinitiator P(MPBP‐co‐DMAEMA) and polymerizable photoinitiator MPBP are similar, and both exhibit high red‐shifted maximal absorption as compared with BP. The photopolymerization of 1,6‐hexanediol diacrylate (HDDA) and trimethylolpropane triacrylate (TMPTA), initiated by MPBP/DMAEMA, MPBP/P(DMAEMA), and P(MPBP‐co‐DMAEMA) systems, was studied by photo‐DSC. The results indicate that P(MPBP‐co‐DMAEMA) is most efficient for the polymerization of both HDDA and TMPTA, and MPBP/P(DMAEMA) is the least efficient of the three photoinitiating systems. Copyright © 2009 John Wiley & Sons, Ltd.     

Photopolymerization of maleimide perfluoropolyalkylethers without a photoinitiator

Perfluoropolyalkylethers derived from hexafluoropropylene oxide were functionalized with maleimide groups. Irradiated by UV‐light, the new maleimide macromonomers demonstrated very fast polymerization kinetics with a curing time as fast as 8 s. The effect on photopolymerization of different features such as the molecular weight of the fluorinated chain and the chain length of the hydrogenated spacer were studied, as well as the influence of the type of photoinitiator and the presence of air. Thermal and surface properties of the UV‐cured polymers were examined and were typical to fluoropolymers in view of water–oil repellent coatings. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 699–707     

含氧光敏引发体系的研究——Ⅵ.二苯酮/三乙胺体系引发光聚合过程中的再次引发效应

过去,作者曾发表了多种光敏引发体系引发烯类单体光聚合的工作,在研究2,2-二甲氧基苯乙酮在氧存在下引发甲基丙烯酸甲酯光聚合时,结合在聚合物链端的引发剂碎片具有光化学活性,在光聚合反应中产生高分子自由基,发生再次聚合,出现高分子量     

光聚合法快速制备甲基丙烯酸酯类毛细管整体柱

采用甲基丙烯酸正丁酯(BMA)为功能单体, 乙二醇二甲基丙烯酸酯(EDMA)为交联剂, 正丙醇、1,4-丁二醇和水为致孔剂, Irgacure 1800为引发剂, 在毛细管内采用光引发原位聚合150 s快速制备了有机聚合物整体柱. 分别采用电色谱(CEC)、加压电色谱(p-CEC)和低压色谱(LPLC)模式对所制备的整体柱进行了性能评价, 基线分离了硫脲、甲苯、萘和联苯, 在加压电色谱(p-CEC)模式下硫脲的最低理论塔板高度达到了8.0 μm. 扫描电镜结果表明, 整体材料在毛细管柱中形成并与毛细管内壁结合紧密.     

气相色谱-质谱法同时测定食品包装葵花籽油模拟液中二苯甲酮和4-甲基二苯甲酮

建立了气相色谱-质谱法同时测定食品包装葵花籽油模拟液中二苯甲酮和4-甲基二苯甲酮迁移量的分析方法.食品包装样品经葵花籽油浸泡后,采用乙腈旋涡提取.提取液经GC-MS测定,采用选择离子监测(SIM)模式进行定性定量分析,外标法定量.两种目标物的检测限分别为0.02mg/kg和0.03mg/kg.在0.2～10mg/kg的...     

A novel alkenoic acid ester and a new benzophenone from Ranunculus ternatus

A novel alkenoic acid ester,(E)-4-hydroxy-dodec-2-enedioic acid-12-O-methyl ester and a new benzophenone,ethyl (S)-3-[2- (3,4-dihydroxybenzoyl)-4,5-dihydroxyphenyl]-2-hydroxypropanoate,together with a known compound,(E)-4-hydroxy-dodec-2- enedioic acids were isolated from the roots of Ranunculus ternatus.Their structures were elucidated by spectroscopic methods.     

UV-induced graft polymerization of acrylamide on cellulose by using immobilized benzophenone as a photo-initiator

Photo-active moiety, benzophenone, was incorporated onto cotton fabrics by using butyl tetracarboxylic acids (BTCA). Then, grafting of polyacrylamide on the cotton fabrics was performed by exposing the fabrics to longer UV wavelength irradiation. The chemical structure and thermal properties of the polyacrylamide grafted cotton fabrics were investigated by SEM, FTIR, XRD, and TGA, and the results verified the successful grafting of polyacrylamide on cotton fabrics. Also, it was observed that active chlorine contents were created on the polyacrylamide grafted cotton fabrics through simple chlorination process, and the chlorine treated cotton fabrics showed excellent antibacterial abilities like the powerful cyclic amide halamines.     

Controlled Radical Photopolymerization of n-Butyl Methacrylate in Bluk Mediated by HTEMPO

Recently, controlled free-radical polymerization (CRP) has been a technique for the preparation of polymers of tailored architectures using experimentally simple techniques1. The CRP methods were nitroxide-mediated free radical polymerization (NMP), atom …     

Stereoselective intramolecular hydrogen abstraction by a chiral benzophenone derivative

An unprecedented stereoselective photoreduction of a chiral BZP is observed in steady state as well as in time-resolved studies.     

Novel PU‐type polymeric photoinitiator comprising side‐chain benzophenone and coinitiator amine for photopolymerization of PU acrylate

A novel diamine 3,5‐diamino‐4′‐phenoxylbenzophenone (DAPBP) was synthesized from the reaction of 3,5‐diamino‐4′‐chlorobenzophenone (DACBP) and phenol. Then through the polycondensation of DAPBP, toluene‐2,4‐diisocyanate (TDI), and N‐methyldiethanolamine (MDEA), we obtained a PU‐type polymeric photoinitiator containing side‐chain benzophenone (BP) and tertiary amine in the same macromolecule (PUSOA). Another polymeric photoinitiator without coinitiator amine in polymer chain (PUSO) was also synthesized for comparison. FT‐IR, ¹H NMR, and GPC analyses confirmed the structures of monomer and polymeric photoinitiators. The UV–Vis spectra of PUSOA, PUSO, and DAPBP are similar, and all exhibit the maximal absorption near 290 nm. ESR spectra indicate that PUSOA can generate active species most efficiently. The photopolymerization of PU acrylate, initiated by PUSOA, PUSO/MDEA, DAPBP/MDEA, and BP/MDEA, was studied by differential scanning photocalorimetry (photo‐DSC). The results show that the in‐chain coinitiator amine can significantly improve the photoefficiency of the polymeric photoinitiator and the PUSOA is more efficient for the polymerization of PU acrylate than its low‐molecular‐weight counterpart. Copyright © 2008 John Wiley & Sons, Ltd.     

甲基丙烯酸基质的毛细管电色谱整体柱的制备与应用

以甲基丙烯酸(MAA)为功能单体,同时又作电渗流改性剂, 乙二醇二甲基丙烯酸酯(EDMA)为交联剂,甲苯和异辛烷为致孔剂,Irgacure 1800为光引发剂,采用紫外光引发原位聚合反应制备出毛细管电色谱整体柱.对影响电渗流的因素如pH、乙腈含量及离子强度等进行了讨论.使用制备的整体柱在3种模式(加压电色谱、气压驱动和电色谱)下对7种中性物质(硫脲、苯、甲苯、乙苯、萘、联苯和菲)的混合物实现基线分离,同时还可实现酸性物质(邻羟基苯甲酸、苯甲酸、苯乳酸、扁桃酸)和碱性物质(苯胺、甲苯胺、乙酰基苯胺和N-甲基苯胺)的快速分离.     

利用电子自旋共振技术捕捉烯类单体双光子聚合反应的自由基信号

<正>自1999年烯类单体的双光子聚合方法被发现以来[1],其产物在光开关制备[2]、光子晶体[3]、微机械[4]及三维微加工[5]等领域得到了广泛的应用.由此,烯类双光子聚合机理也成为人们研究的焦点[6].到目前为止,研究者们普遍认为烯类单体的双光子聚合反应属于自由基历程,各种利用双光子     

Reductive coupling of 1,3-dimethyluracils with benzophenone by low-valent titanium: unusual two-to-one coupling

The reductive coupling of 1,3-dimethyluracil with benzophenone by Zn-TiCl₄ in THF gave unusual two-to-one adduct and its further reduced product. The reductive coupling of 1,3-dimethyl-5-fluorouracil with benzophenone by Zn-TiCl₄ also gave two-to-one adduct. 1,3-Dimethylthymine was, however, completely inert under the same conditions.     

The Photopolymerization Kinetics of Acryl amide Sensitized with Toluidine Blue-Alcoholamine Induced by He-Ne Laser

Toluidine blue(TB) is a good sensitizer for the polymerization of acrylnmide(AM) induced by He-Ne laser. With TB as a sensitizer and various alcoholamine as donors, the photoredox of TB and the polymerization kinetics of AM induced by He-Ne laser were investigated. It was found that either for the photoredox of TB or for the polymerization of AM, the activity of alcoholamine increases in the order of EOA相似文献   

Direct ether formation of semibenzopinacol moieties in a photopolymerization system featured constant intensity of absorbed light

In a special photopolymerization reaction system, the reactivity of semibenzopinacol moieties was examined. Structural analysis by 1D/2D NMR showed that the hydroxyl groups of the semibenzopinacol moieties after hydrogen abstraction reaction have reacted directly to form a new ether structure instead of the cleavage of a C-C bond in a photopolymerization system featured constant intensity of absorbed light when there is only vinyl acetate added. In order to clarify this new reaction, comparative experiments and several characterization methods were applied. Results revealed that poly(vinyl acetate) radicals initiated by UV irradiation or benzophenone/triethanolamine system, and UV irradiation under or above 300 nm, were two necessary factors for the formation of the new ether structure from hydroxyl groups of semibenzopinacol moieties.