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1.
用Photo-DSC(光差热扫描)研究了一种可聚合胺助引发荆乙二醇-3-吗啡啉丙酸酯甲基丙烯酸酯(EGMPM)分别与二苯甲酮(BP)、4-(4-甲苯硫基苯基)苯基甲酮(BMS)、4-氯二苯甲酮(CBP)、4-氯甲基二苯甲酮(CMBP)、4-羟甲基二苯甲酮(HMBP)等二芳酮组成的光引发体系引发以1,6-己二醇二丙烯酸酯(HDDA)为单体的紫外光聚合动力学.考察二芳酮质量分数、聚合温度、光照强度对其光聚合动力学影响,并评价其引发效果;同时计算出了EGMPM/BP引发HDDA聚合体系的活化能.结果表明,二芳酮的质量分数增加时,反应达到最大反应速率的时间减少,单体的转化率也相应增加,单体聚合速率相应增大;相同质量分数(0.1%)的不同二芳酮,BMS体系达到最大反应速率的时间最短,单体转化率也最高;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少.  相似文献   

2.
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.  相似文献   

3.
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.  相似文献   

4.
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.  相似文献   

5.
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。  相似文献   

6.
DPPH引发丙烯酸酯单体光聚合动力学研究   总被引:1,自引:0,他引:1  
徐娟  蒋姗  王克敏  俞强  马贵平  聂俊 《粘接》2011,(3):44-47
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。  相似文献   

7.
吗啡啉基-N-甲酸-丙烯酸乙二醇酯光聚合动力学的研究   总被引:2,自引:0,他引:2  
采用实时红外技术对所合成的活性稀释剂吗啡啉基-N-甲酸-丙烯酸乙二醇酯的聚合动力学进行了测试。研究了光强和引发剂浓度对其光聚合的影响。结果表明随光强增加,聚合速率提高,当光强足够高时继续增加光强聚合速率反而会降低;当引发剂浓度升高时,聚合速率也越快,但当引发剂浓度足够高时继续增加引发剂浓度会使聚合速率下降。  相似文献   

8.
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。  相似文献   

9.
合成了不含氢键的低粘度的吡咯烷基-N-甲酸-丙烯酸乙二醇酯(PLW),并采用实时红外光谱法检测了光强和光引发剂浓度对光聚合动力学的影响。随着光强的增加光聚合的最终转化率基本不变,但是光聚合速率有明显的增加,并且达到最大聚合速率的时间也缩短。随着光引发剂浓度的增加,最终转化率和最大聚合速率都有了显著的增加。所合成单体的转化率在30 s内能达到90%以上。  相似文献   

10.
以多官能度过氧化物3,6,9-三甲基-3,6,9-三乙基-1,4,7-三过氧烷为引发剂,采用本体聚合法制备高抗冲聚苯乙烯,考察了各反应条件对预聚合动力学的影响。结果发现:聚合温度由125℃逐渐升高到145℃和引发剂质量分数由O.0075%增加到0.0200%时,聚合速率逐渐加快;当引发剂质量分数高于0.0200%时,聚合速率变化不大;随着基础胶质量分数由5%增加到15%和乙苯质量分数从10%增加到30%,聚合速率逐渐降低。不同引发剂引发聚合的效果与其官能度、半衰期及聚合温度等因素有关。  相似文献   

11.
Kwame Owusu-Adom 《Polymer》2008,49(11):2636-2643
Photopolymerization kinetics of polymer-clay nanocomposite systems utilizing polymerizable quaternary ammonium surfactants as dispersants were systematically investigated to determine the effects of surfactant type and clay morphology on polymerization behavior. For these studies, either polymerizable surfactants were mixed into a clay-monomer system or the surfactants were ionically anchored to clay surfaces and added to the monomer for in situ photopolymerization. Higher photopolymerization rates are observed with increasing polymerizable surfactant concentration, while no significant change or decreases in polymerization rate occur with incorporation of non-polymerizable surfactants. The higher rates observed for polymerizable surfactant systems are due to lower apparent termination rate parameters stemming from immobilization of the surfactants. For clay that is modified with ionically bonded quaternary ammonium surfactants, polymerization rates decrease in both polymerizable and non-polymerizable organoclay systems with increasing concentration, but this decrease is much smaller when polymerizable organoclays are utilized. For the same organoclay concentration, higher polymerization rates and double bond conversions result with increasing polymerizable surfactant concentration via cation exchange. Significant increases in polymerization rate also occur with increasing degree of clay exfoliation.  相似文献   

12.
Hybrid monomer, 4‐(1‐propenyl)oxybutyl acrylate, with cationic and free radical polymerizable group was synthesized. Real‐time Fourier transform infrared spectroscopy (FTIR) was used to monitor the photopolymerization kinetics of the monomer. Photopolymerization processing conditions, such as light intensity, photoinitiator concentrations have been evaluated. It was found that hybrid monomer showed higher efficiency of photopolymerization in comparison with the blend system. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

13.
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  相似文献   

14.
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  相似文献   

15.
通过麦克尔加成反应合成了不同链长的脂肪胺助引发剂,采用了实时红外技术对其光聚合性能进行研究,考察了不同胺链长、光引发剂浓度,不同单体对光聚合性能的影响。结果表明,随着链长的增加,光聚合反应速率和转化率没有多大的差别,在所研究的浓度范围内,随着助引发剂用量的增加,光聚合反应速率和转化率都相应的增加,对于二苯甲酮的选择有一个最佳用量,而二苯甲酮的结构对光聚合反应速率也有一定的影响,另外随着单体的官能度的增加,光聚合的反应转化率降低。  相似文献   

16.
The kinetics of non‐stationary photopolymerization (post‐polymeryzation) of some diacrylates at the wide range of initial conversions was investigated. All kinetic curves has two regions: quick and short, slow and long. Experimental results were compared with the kinetic model of the photoinitial three‐dimensional photopolymerization. It was determined that kinetic model allows us to describe the process of the post‐polymerization in the whole range of conversions. The rate constants of the linear break of the primary and secondary chains in the interphase layer were estimated. The increasing rate constants in the interphase are the similar for investigated diacrylates and do not depend on the glicol chain. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1892–1895, 2002  相似文献   

17.
A facile and efficient strategy for the preparation of polymer grafts on zirconia particles is developed by means of self‐initiated photografting and photopolymerization. The UV‐induced grafting polymerization is applicable to a variety of polymerizable monomers, allowing the direct formation of homogeneous and stable polymer coatings on zirconia particles without any initiator immobilization. The as‐prepared polymer grafts are proved to be efficient supports for polyoxometalates as H3PW12O40 can be uniformly and stably immobilized on a poly(4‐vinylpyridine) layer through electrostatic interaction. The resulting hybrid catalyst system, associated with high catalytic activity for a series of oxidation reactions such as amines, alkenes, alcohols and sulfides, represents a novel and efficient system with a high catalyst loading capacity and stability upon reuse in further cycles. © 2014 Society of Chemical Industry  相似文献   

18.
Bisbenzo[1,3]dioxol‐5‐ylmethanone (BBDOM), a type of hydrogen‐abstraction photoinitiator, exhibited redshifted maximal absorption in comparison with benzophenone (BP) according to ultraviolet–visible absorption spectroscopy. The kinetics of photopolymerization of the photoinitiator in different systems was studied with real‐time infrared spectroscopy. The concentration of BBDOM, the components of the initiator, and the functionality of the monomer had great effects on the kinetics of photopolymerization. The results show that BBDOM is a more effective photoinitiator than BP. BBDOM consists of cyclic acetals that are widely distributed in nature, and with BBDOM, the use of large numbers of amines can be avoided in the system without the requirement of an additional hydrogen donor. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

19.
The photopolymerization of vinyl monomers was studied by the system of metal-amine complex and carbon tetrachloride. Addition of amines to the initiating system generally accelerates the polymerization. The acceleration by various sorts of amines in different solvents was examined. It was confirmed that the photopolymerization in question is of free radical character. The polymerization mechanism was discussed.  相似文献   

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