二苯酮-可聚合胺引发1，6-己二醇二丙烯酸酯的光聚合研究

以UV-Vis分光光度计法和Photo-DSC法分别研究了合成的3种可聚合胺类助引发剂DMPDA、EGDPM、EGMPM与二苯甲酮（BP）组成的引发体系的光化学初级过程及引发1，6-已二醇二丙烯酸酯（HDDA）的紫外光聚合动力学．考察了助引发剂胺的含量对BP的光化学初级过程和对引发HDDA光聚合动力学的影响，以及光强和温度对聚合动力学的影响．结果表明，随着胺含量的增加，BP的光化学初级反应速率增加，从而使体系的聚合反应速率增加．随着温度和光强的增加，单体最终转化率、最大反应速率增大，达到最大反应速率所需的时间减小．     

可聚合型光引发剂4-丙烯酰氧基二苯甲酮的光聚合性能研究

以实时红外光谱（RT-IR）法研究了合成的4-丙烯酰氧基二苯甲酮（4-ABP）的光聚合动力学性质，考察了不同单体、不同引发剂和助引发剂浓度、不同光强对聚合性能的影响．以萃取法对比研究了4-ABP和二苯甲酮（BP）在固化膜中的的残留量．结果表明，4-ABP是一种非常有效的光引发剂．随着引发剂浓度和光强的增大，单体转化率、最大反应速率都增大，诱导期缩短．萃取实验表明4-ABP在固化膜中的残留量远低于BP．     

樟脑醌／乙二醇-3-吗啡啉基丙酸酯甲基丙烯酸酯引发牙科复合树脂的光聚合动力学研究

采用Photo-DSC研究了樟脑醌（CQ）／乙二醇-3-吗啡啉基丙酸酯甲基丙烯酸酯（EGMPM）可见光引发牙科复合树脂聚合的动力学过程．考察了CQ浓度、EGMPM浓度以及光强对牙科修复复合树脂光聚合动力学的影响．结果表明：增加引发体系的浓度和增加光强都可以增加反应速率和转化率；同时实验结果验证了Rp∝（I0[CQ][EGMPM]）^1／2的动力学关系．     

二苯甲酮环缩醛单组分光引发剂的合成与光聚合性能的研究

本文合成了一种新型二苯甲酮基复合光引发剂5-(4'-苯甲酰基苯甲氧基)-1,3-二氧苯并环戊烷(BPCH2BDO),利用FIR、1HNMR对其结构进行表征。并采用实时红外光谱研究了BPCH2BDO光引发剂引发丙烯酸酯类单体的光聚合行为。结果表明,该引发剂的最大吸收光谱在258 nm,随着紫外光照的进行,BPCH2BDO的最大吸收峰258 nm逐渐减少。当引发剂的浓度不断增大时,单体的反应速率和该体系的反应程度先增大后减小;随着光照强度增大,单体转化率和最大聚合速率都增大。BPCH2BDO与传统的光引发剂二苯甲酮/4-二甲基氨基苯甲酸乙酯(BP/EDAB)引发效率相当。     

基于α-羟烷基苯酮（HAPK）可聚合大分子光引发剂的合成及其引发三丙二醇双丙烯酸酯（TPGDA）光聚合动力学的研究

以α-羟烷基苯酮(HAPK)、甲苯-2,4-二异氰酸酯(TDI)、聚乙二醇600(PEG600)和丙烯酸-β-羟乙酯(HEA)为原料,通过3步反应,合成了一种可聚合大分子光引发剂:HAPK-TDI-PEG600-TDI-HEA(HTPTH).用IR对反应过程进行了监测.通过Photo-DSC研究了HTPTH引发三丙二醇双丙烯酸酯(TPG-DA)光聚合动力学,考察了光强、引发剂浓度对TPGDA光聚合动力学的影响.结果表明,随着引发剂浓度和光强的增大,最大反应速率对应的转化率、单体最终转化率、最大反应速率都增大,达到最大反应速率所需的时间减小.     

铁—芳烃配合物引发环氧化合物的光引发阳离子聚合

以环戊二烯基异丙苯铁六氟磷酸盐为光引发剂，用等温差示扫描量热法（ＤＳＣ）研究了对甲苯基缩水甘油醚（ＣＧＥ）的光引发阳离子聚合的温度效应及聚合反应动力学。研究表明ＣＧＥ聚合时，反应速率及最终转化率随温度变化在５５℃及４５℃左右有一个峰值。ＣＧＥ光聚合反应速率与单体浓度的一次方成比例，其反应机理包括两个基本反应，即：引发剂光解产物与单体的配合反应以及在该配合物中单体的开环反应，而这两个反应具有相反的温     

2-(4-甲氧基苯基)-4,6-双(三氯甲基)-S-三嗪光引发剂的合成及其光聚合动力学性能研究

以对甲氧基苯甲腈和三氯乙腈为原料合成了光引发剂2-(4-甲氧基苯基)-4,6-双(三氯甲基)-S-三嗪(MBTT),通过傅里叶红外光谱仪、核磁共振仪和紫外吸收光谱对所合成的产物结构进行了表征.并利用实时红外(RT-IR)对该引发剂进行了光聚合反应动力学研究,考察了单体、引发剂浓度和光强对引发速率及单体转化率的影响.结果表明,MBTT是一种高效的紫外光引发剂,在引发剂用量为0.1%时光聚合的单体转化率就能达到90%;随着光强的增大,单体的双键转化率和最大反应速率都增大,诱导期缩短;双丙烯酸酯类单体的双键转化率比三丙烯酸酯类单体的双键转化率要高.     

铁－芳烃配合物引发环氧化合物的光引发阳离子聚合

以环戊二烯基异丙苯铁六氟磷酸盐为光引发剂，用等温差示扫描量热法（ＤＳＣ）研究了对甲苯基缩水甘油醚（ＣＧＥ）的光引发阳离子聚合的温度效应及聚合反应动力学。研究表明ＣＧＥ聚合时，反应速率及最终转化率随温度变化在５５０℃及４５０℃左右有一个峰值．ＣＧＥ光聚合反应速率与单体浓度的一次方成比例，其反应机理包括两个基本反应，即：引发剂光解产物与单体的配合反应以及在该配合物中单体的开环反应，而这两个反应具有相反的温度效应，升高温度有利于后者而不利于前者．     

水溶性光引发剂二苯甲酮氯化铵引发三丙二醇双丙烯酸酯光聚合动力学的研究

以4-羟基二苯甲酮、环氧氯丙烷和三甲胺盐酸盐为原料,通过2步反应,合成了一种水溶性光引发剂——氯化[2-羟基-3-(4-苯甲酰基苯氧基)-N,N,N-三甲基-1-丙铵](HBPCl)。其结构通过核磁共振氢谱(1H-NMR)和傅里叶红外光谱(FT-IR)得到了证实。研究了水溶性光引发剂HBPCl的紫外吸收和降解特性,并通过实时红外(RT-IR)研究了氢助剂含量、HBPCl浓度和光强对HBPCl引发的TPGDA光聚合动力学的影响。结果表明,HBPCl在285 nm处有最大紫外吸收峰,能够有效地引发单体聚合;另外,随着氢助剂含量、引发剂浓度和光强的增大,光聚合速率和单体最终转化率随之增大,诱导期被缩短。     

DPPH引发丙烯酸酯单体光聚合动力学研究

采用傅立叶红外光谱仪、核磁共振仪对阳离子光引发剂4-(苯硫基)苯基二苯基硫鎓六氟磷酸盐(DPPH)结构进行了表征,紫外光谱分析表明该引发剂在302nm处有最大紫外吸收。通过实时红外(RT-IR)对DPPH引发丙烯酸酯单体光聚合动力学过程进行了研究,考查了引发剂浓度、光强及不同官能度单体对双键转化率及聚合速率的影响。随引发剂浓度增加,最大转化速率先增大后减小,而光强增加,最大转化速率增加。单体官能度越高,双键转化率与最大转化速率越低,达最大转化速率的时间越长。     

A polymerizable photosensitizer and its photopolymerization kinetics

A previously reported polymerizable benzophenone photosensitizer, 2‐methacryloxyethyl 4‐benzoylbenzoate (MEBB), was synthesized and characterized. The photopolymerization kinetics of methyl α‐hydroxymethylacrylate (MHMA) and 1,6‐hexanediol diacrylate (HDDA) initiated with MEBB or benzophenone (BP) in the presence or absence of amine co‐initiators were determined by photo‐differential scanning calorimetry. The results indicate that benzophenone with a p‐carbonyl substitutent is more efficient in photoinitiation when compared to the non‐substituted benzophenone analogue. The final monomer conversions in the presence of amine co‐initiators are slightly higher than without them. Copyright © 2005 Society of Chemical Industry     

Effect of N‐phenylmaleimide on a novel chemically bonded polymerizable photoinitiator comprising the structure of planar N‐phenylmaleimide and benzophenone for photopolymerization

A novel chemically bonded polymerizable photoinitiator 4‐[(4‐maleimido)phenoxy]benzophenone (MPBP) comprising the structure of planar N‐phenylmaleimide (NPMI) and benzophenone (BP), compared with the physical mixtures of NPMI/BP or NPMI/4‐hydroxybenzophenone, was investigated to disclose the mutual influence between NPMI and BP. A BP derivative, 4‐phenoxylbenzophenone, was selected as the model compound. Electron spin resonance spectra of such photoredox systems indicated MPBP and BP possess the same initiation mechanism. The large red‐shifted π–π* absorption of MPBP should be because of the phenoxyl group in MPBP but not the maleimide group. The photopolymerization of methyl methacrylate (MMA) and 1,6‐hexanediol diacrylate (HDDA) initiated by those systems, using the unsaturated tertiary amine N,N‐dimethylaminoethyl methacrylate (DMAEMA) as the coinitiator (H donor), was studied through dilatometry and photo‐differential scanning calorimetry. The results showed that MPBP was more efficient for the photopolymerization of MMA and HDDA than its physical mixture counterpart. The high efficiency of MPBP may be mainly because of the interaction between NPMI and BP group but not the phenoxyl group alone. A certain amount of NPMI can accelerate the photopolymerization when added to the formulations, but too much NPMI will eventually decrease the photoefficiency. Copyright © 2006 Society of Chemical Industry     

ESR and kinetic study of a novel polymerizable photoinitiator comprising the structure of N‐phenylmaleimide and benzophenone for photopolymerization

A novel polymerizable photoinitiator, 4‐[(4‐maleimido)phenoxy]benzophenone (MPBP) comprising the structure of N‐phenylmaleimide and benzophenone was used for the photopolymerization with N,N‐dimethylaminoethyl methacrylate (DMAEMA) as coinitiator. The ESR spectrum of this photoredox system was studied and compared with BP/DMAEMA; the results showed the same signals of them and verified that N‐phenylmaleimide does not generate radicals. The kinetics for photopolymerization of methyl methacrylate (MMA) using such system was studied by dilatometer. It was found that the polymerization rate was proportional to the 0.3172th power of the MPBP concentration, the 0.7669th power and the 0.1765th power of MMA concentration and DMAEMA concentration respectively; the overall apparent activation energy obtained was 31.88 kJ/mol. The polymerization kinetics of 1,6‐hexanediol diacrylate (HDDA) initiated by such system was studied by photo‐DSC. It showed that the increase in the MPBP concentration, light intensity, and temperature leads to increased polymerization rate and final conversion. The apparent activation energy was 11.25 kJ/mol. This polymerizable photoredox system was significantly favorable for reducing the migration of active species but owning high efficiency. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2347–2354, 2006     

Novel polymerizable N‐aromatic maleimides as free radical initiators for photopolymerization

Four kinds of polymerizable N‐aromatic maleimides (MIs)—4‐[(4‐maleimido)phenoxy]benzophenone (MPBP), 4,4′‐bis[(4‐maleimido)phenoxy]benzophenone (BMPBP), 4‐maleimidobenzophenone (MBP), and 4,4′‐bismaleimidobenzophenone (BMBP)—were synthesized as free radical photoinitiators, by introducing directly N‐phenylmaleimide groups or maleimide groups into the molecule of benzophenone (BP). Compared with BP, their UV‐visible spectra have a significantly red‐shifted maximum absorption. The maximum absorption of MIs containing bifunctional maleimide groups is slightly larger than the corresponding monofunctional ones. Choosing an unsaturated tertiary amine N,N‐dimethylaminoethyl methacrylate (DMAEMA) as coinitiator, the photopolymerization of 1,6‐hexanediol diacrylate (HDDA), initiated by these four MIs, was studied through photo‐DSC. The results show that all the MIs are dramatically more efficient than BP. Among them, MPBP is the most efficient, in which the polymerization rate is almost three times as high as that of the BP system. Photoinitiators containing bifunctional maleimide groups, though having higher final conversion, are less efficient than the corresponding monofunctional ones. These polymerizable photoredox systems significantly reduced the migration of the active species, leading to their higher efficiency. Copyright © 2006 Society of Chemical Industry     

Benzophenone-di-1,3-dioxane as a novel initiator for free radical photopolymerization

Benzophenone-di-1,3-dioxane (BP-DDO), a novel photoinitiator for free radical polymerization, was synthesized and characterized. The photopolymerization kinetics of BP-DDO was studied by real-time infrared spectroscopy (FT-IR). When this photointiator was used to efficiently initiate polymerization of acrylates and methacrylates, there was an optimum cure rate with the increase in BP-DDO concentration. Both the polymerization rate and final conversion increased with the increase in light intensity. The kinetics study of photopolymerization of TMPTA showed that BP-DDO was a more effective photoinitiator than benzophenone and benzophenone/ethyl-4-dimethylaminobenzoate (EDAB).     

Cyclic acetal as coinitiator for bimolecular photoinitiating systems

Cyclic acetals were used to replace the conventional amines in bimolecular photoinitiating systems. The mixtures of benzophenone derivatives and cyclic acetals were used to initiate the UV photopolymerization of 1,6-hexanedioldiacrylate (HDDA). Camphorquinone (CQ)/1,3-benzodioxole (BDO) combinations were used to initiate the visible light photopolymerization of 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]propane (BisGMA)/triethylene glycol dimethacrylate (TEGDMA) (70/30 wt%) for dental application. The kinetics was recorded by real-time infrared spectroscopy (RTIR). Ethyl 4-N,N-dimethylaminobenzoate (EDMAB) was used as control in the same photocuring condition. The results showed that the addition of cyclic acetals greatly increased the rate of polymerization (R_p) and final double bond (DC) of HDDA. Combination of p-chlorobenzophenone (CBP)/BDO had the highest initiating reactivity. BDO also showed an effective coinitiator for camphorquinone-based initiator system. Comparing with EDMAB, CBP/BDO and CQ/BDO indicated comparable initiating reactivity. Moreover, the natural component characteristics of BDO made it a promising alternative to commercial amine in biomolecular photoinitiating system.     

Novel chemical-bonded polymerizable sulfur-containing photoinitiators comprising the structure of planar N-phenylmaleimide and benzophenone for photopolymerization

As a continuation of the research on chemical-bonded photoinitiators comprising the structure of planar N-phenylmaleimide (NPMI) and benzophenone (BP), three novel polymerizable sulfur-containing photoinitiator MTPBP, CMTPBP and BMTPBP were synthesized by introducing NPMI group into benzophenone (BP). BP was selected as the reference to evaluate their photoefficiency. These novel photoinitiators possess greatly red-shifted UV maximal absorption, and their fluorescence emission varies. Three representative types of different functionality monomers, methyl methacrylate (MMA), 1,6-hexanediol diacrylate (HDDA) and trimethylolpropane triacrylate (TMPTA), initiated by the three novel photoinitiators were studied through dilatometer and photo-DSC using unsaturated tertiary amine N,N-dimethylaminoethyl methacrylate (DMAEMA) as the coinitiator. The results show surprising high efficiency of these chemical-bonded photoinitiators towards different monomers in contrast to BP, and they can initiate photopolymerization without the coinitiator because of the photolysis at C-S bond. The results also verify that the higher viscosity of monomers and the larger molecular size of the photoinitiators may restrict the bimolecular H-abstraction reaction.     

Synthesis and photopolymerization kinetics of polymeric one‐component type II photoinitiator containing benzophenone moiety and tertiary amine

A polymeric one‐component type II photoinitiator (PDABPP) based on 4,4′‐dihydroxybenzophenone (DHBP), acryloyl chloride, and piperazine was synthesized, and its structure was confirmed by GPC and ¹H NMR. The photopolymerization kinetics of the photoinitiator was studied by real‐time infrared spectroscopy. It indicated that PDABPP was a more effective photoinitiator than that of benzophenone (BP)/triethylamine (TEA). The rate of polymerization and final conversion increased, and the induction period shortened with increase of PDABPP concentration, light intensity, and amine concentration. The kinetics of photopolymerization for tripropylene glycol diacrylate (TPGDA) incorporating PDABPP in the presence of different tertiary amines as the initiating system indicated that the PDABPP/TEA combination exhibited the highest polymerization rates among the PDABPP/amines combinations. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers     

1,3-dioxane methylcoumarin as a novel photoinitiator for free radical polymerization

1,3-Dioxane methylcoumarin (DOMC), a novel photoinitiator (PI) for free radical polymerization, was synthesized and characterized. UV–vis absorption spectroscopy was used to investigate its photochemical behavior during the photophysical process. The photopolymerization kinetics of DOMC was studied by real-time infrared spectroscopy (FTIR). There was an optimum curing rate with the increase in DOMC concentration. Both the polymerization rate and final conversion increased with the increase in light intensity. DOMC was the most efficient PI for tripropylene glycol diacrylate (TPGDA) in different acrylate monomers. The kinetics study of TPGDA photopolymerization showed that DOMC was a more effective PI than benzophenone/ethyl-4-dimethylaminobenzoate. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Kinetic investigations on the UV‐induced photopolymerization of nanocomposites by FTIR spectroscopy

The kinetics of the photopolymerization for nanocomposites containing nanosilica with 2,2‐dimethoxy‐1,2‐diphenylethan‐1‐one or benzophenone/n‐methyl diethanolamine (BP/MDEA)as photoinitiators were studied by FTIR spectroscopy. It was found that nanocomposites containing nanosilica had higher conversion in comparison with pristine EA. The presence of MPS and ethanol accelerated the photopolymerization of nanocomposites, while the presence of water decelerated it. The photopolymerization of nanocomposites was more sensitive to oxygen than that of pristine EA. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99:1429–1436, 2006