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1.
通过3步反应合成了一种新型杂化单体4-(1-丙烯基)氧丁基缩水甘油醚(POBGE)。使用傅立叶红外光谱和核磁共振仪对相应产物结构进行了表征。同时使用傅立叶实时红外(FT-RTIR)对该杂化单体的光聚合性能进行了研究。考察了引发剂种类,不同浓度光引发剂,不同光照强度对杂化单体的光聚合性能的影响。结果表明,光引发剂硫鎓盐的引发性能要优于碘鎓盐,随着光引发剂浓度以及光照强度的增大杂化单体双键及环氧基团的转化率都相应提高。  相似文献   

2.
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.  相似文献   

3.
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   

4.
以2-硝基噻吩,甲基磺酰氯及苯乙腈为原料合成了一种紫外光产酸剂(5-甲磺酸酯亚胺-5H-噻吩-2-亚基)-苯基-乙腈(MTPA),通过傅里叶红外光谱仪、核磁共振仪和紫外吸收光谱仪及热重分析对所合成的产物的结构和性能进行了表征,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、产酸剂浓度对引发速率及单体转化率的影响。结果表明,在一定浓度范围内,随着引发剂浓度增大,聚合速率加快,最终的双键转化率也增高。  相似文献   

5.
二苯基六氟砷酸碘鎓盐引发四氢呋喃的正离子光聚合   总被引:1,自引:0,他引:1  
以二苯基六氟砷酸碘钅翁盐为引发剂,吖啶黄和安息香二甲醚为增感剂,在紫外光光照情况下,引发四氢呋喃(THF)进行了正离子聚合,讨论了吖啶黄和安息香二甲醚的增感机理,研究了二苯基六氟砷酸碘钅翁盐引发THF的后聚合反应。结果表明,在紫外光光照的情况下,二苯基六氟砷酸碘钅翁盐可以引发THF聚合,证明二苯基六氟砷酸碘钅翁盐是一种正离子光聚合引发剂;吖啶黄及安息香二甲醚对二苯基六氟砷酸碘钅翁盐引发THF聚合具有显著的增感作用;安息香二甲醚增感的二苯基六氟砷酸碘钅翁盐引发的THF后聚合具有明显的活性聚合趋势,转化率与特性黏数呈线性增长关系;通过紫外光引发聚合的方式可以制备相对分子质量分布为1·028、数均相对分子质量为1·004×104、转化率大于85%的聚四氢呋喃。  相似文献   

6.
为了延长二苯甲酮光引发剂的吸收波长,使其与LED光源更好的匹配,本研究将苄氨基基团引入二苯甲酮结构,合成了3种4-双苄胺基二苯甲酮衍生物,其吸收波长延长至400 nm,与不同波长(365~405 nm)的LED光源能较好的匹配。利用实时红外对其光聚合动力学进行测试,通过电化学测试以及光降解测试等对其作用机理进行研究。结果表明:双苄胺基二苯甲酮衍生物是一类高效的LED光引发剂,其可作为单组分光引发剂引发1,6-己二醇二丙烯酸酯发生自由基聚合,双键转化率可达80%~83%。与碘鎓盐复配,引发阳离子聚合时环氧单体转化率可达45%,引发自由基-阳离子混杂光固化时双键转化率为69%~71%,环氧单体转化率为58%~61%,在自由基聚合及互穿网络聚合物结构光固化材料制备方面存在潜在应用价值。  相似文献   

7.
采用两步法合成了可紫外光固化的异氰酸酯改性的环氧丙烯酸酯树脂,并利用元素分析、傅里叶变换红外光谱、核磁共振氢谱对此树脂的结构进行了表征。对树脂及其固化后涂膜的性能测试表明,合成的树脂具有较低的黏度,为4500mPa-s/60℃,固化膜柔韧性能优,低于3mm。采用红外光谱法对此改性树脂的光固化动力学行为进行了分析,结果表明:光引发剂Irgacure1000作为Darocur1173和Irgacure184以质量比1:1构成的复合型光引发剂,比单一的光引发剂具有更优异的引发效果;随着光引发剂Irgacure1000用量的增加,树脂体系光固化反应的聚合速率和树脂中双键的最终转化率都明显增加,但当其用量超过树脂质量的3%时,光固化反应速率和双键的最终转化率又趋于下降;活性单体对树脂光固化行为的影响为:单体的官能度越低、活性单体的用量越大,越有利于树脂的光固化,固化速率和双键的最终转化率都明显提高;此外,增大入射光的光照射强度也有利于树脂的光固化。  相似文献   

8.
采用实时红外光谱技术(RTIR)研究了邻羟基环己基丙烯酸酯(HCA)光聚合反应动力学,探讨了光照强度、光引发剂种类和浓度对其光聚合动力学的影响,并与脂肪族羟基丙烯酸酯单体丙烯酸羟乙酯(HEA)进行了对比。结果表明,最终双键转化率和相对反应速率随光强增大而增加;光引发剂浓度对最终双键转化率和反应速率的影响随引发剂不同呈现不同规律;与HEA相比,HCA具有更高的反应活性,但最终双键转化率较低。  相似文献   

9.
合成了一种全新的自引发纯丙烯酸酯,利用实时红外光谱技术研究了自引发感光高分子的光聚合过程,比较了不同引发剂浓度下的聚合速率和转化率;结果表明,引入到高分子侧链的自由基引发剂仍具有较高的引发活性,双键基团也具有很好的光聚合反应活性。  相似文献   

10.
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   

11.
Three new bisglycidyl monomers; 1,4‐bis((2‐hydroxy‐3‐methacryloxypropoxy) methyl)benzene (MB‐Phe‐OH), 1,4‐bis(2‐hydroxy‐3‐methacryloxypropoxy)2‐cis‐butene (MB‐Cis‐OH), and 1,7‐bis(2‐hydroxy‐3‐methacryloxypropoxy)heptane (MB‐1,7‐OH); were synthesized and used as Bis‐GMA/TEGDMA (bisphenolglycidyl methacrylate/triethylene glycol dimethacrylate) composite resin additives. Flexural properties and double bond conversion of the dental resins composed of silanizated inorganic filler and organic matrices containing new monomers were evaluated. The composite resins formulated, using the monomers MB‐Cis‐OH and MB‐1,7‐OH, have mechanical properties and double bond conversion comparable with those of Bis‐GMA/TEGDMA composite resin used as control. The composite containing the new monomer MB‐Phe‐OH has better flexural properties (flexural strength 65.01 MPa and flexural modulus 5675.91 MPa) than the control composite resin (flexural strength 52.85 MPa and flexural modulus 4879.72 MPa); this could be attributed to the molecular structure of the monomer and its high double bond conversion level of 74.19%. The new bisglycidyl methacrylate monomer MB‐Phe‐OH could be potentially useful in the development of new organic matrices for dental composite resins with high double bond conversion and enhanced mechanical properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40971.  相似文献   

12.
牛莹  王雪萍  聂俊  何勇 《涂料工业》2020,50(3):8-14
选用 6种不同结构的小分子二元羟基化合物、异佛尔酮二异氰酸酯和丙烯酸羟乙酯或季戊四醇三丙烯酸酯为原料,合成了 12种不同结构的低相对分子质量氨基甲酸酯丙烯酸酯( UA)与 2种已商业化应用的不添加二元羟基化合物的无间隔结构 UA对比样品。采用红外光谱进行结构表征,通过实时红外光谱研究了各样品的光聚合动力学,并进行了体积收缩率、力学性能与常规表面性能测试,研究了链长和链段结构类型对 UA综合性能的影响。结果表明:带有小分子二元羟基化合物结构的低相对分子质量 UA样品具有柔韧性好、硬度高、刚性高、体积收缩率低、双键转化率高等优点,并且样品对 PET膜和 ABS基材有较高的附着力。  相似文献   

13.
Ebru Oral  Nicholas A. Peppas 《Polymer》2004,45(18):6163-6173
Mechanisms of interaction of a three-dimensional polymer with solutes are of interest in the development and function of synthetic biomimetic polymers. We have investigated the effects of template/monomer interactions and template concentration on conversion and polymerization rates of a molecularly imprinted polymer. Copolymers of 2-hydroxyethyl methacrylate (HEMA) and poly(ethylene glycol) dimethacrylate (PEG600DMA) were prepared in the presence of glucose. The polymerization reaction kinetics of non-imprinted networks as well as those imprinted with glucose at concentration ratios of [HEMA]/[Glucose] between 11 and 1 were monitored in situ by ATR-FTIR spectroscopy and differential photocalorimetry (DPC). The rates of polymerization for imprinted polymers showed an early lag period followed by a late autoacceleration, indicative of the complexation between monomer and template. Hydrogen-bonding was also observed using FTIR through the CO (carbonyl) bond of the monomers by FTIR. A significant effect of the template on conversion and polymerization rate of imprinted polymers was observed compared to non-imprinted ones. These values provide guidelines for kinetic models of interacting systems.  相似文献   

14.
采取两步法合成了高官能度聚氨酯丙烯酸酯,用实时红外光谱研究了多官能度聚氨酯丙烯酸酯的光聚合动力学,并研究了多官能度聚氨酯丙烯酸酯与其它单体配方的机械性能。研究发现随着丙烯酸官能度的增多,双键转化率也随之降低;官能度的增加会提高漆膜的硬度。  相似文献   

15.
Summary The polymerizability of micelle-forming quaternary ammonium monomers, which were derived from a methacrylic ester and styrene, carrying a polymerizable double bond close to the head group (Type H) or at the alkyl chain end (Type T) including a new monomer, 5-(p-vinylphenyl)pentyltrimethylammonium bromide, has been investigated above their critical micelle concentrations in water. The results are explained on the basis of the structure of the obtained polymers as well as the micelle structure of the monomers in water. The Type H monomers were able to thermally polymerize, while the Type T monomers could not.  相似文献   

16.
The development of a detailed kinetic model describing some of the unusual effects observed in catalyzed olefin polymerization is presented. Based on the method of moments, the model describes the rate effects of hydrogen and comonomers, as well as the ability of certain systems to incorporate long chain branches via internal and/or terminal double bond polymerization. Examples are provided demonstrating the model's ability to predict rates and degrees of polymerization with ethylene, propylene, and 1-hexene monomers. In the case of propylene, multiple insertion mechanisms are modeled and compared with experimental sequence length and end group data. In other examples the model is used to simulate an oscillating metallocene catalyst and a metallocene catalyst capable of branch addition via terminal double bond polymerization. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:1053–1080, 1997  相似文献   

17.
To prepare antibacterial dental resin, a series of novel urethane dimethacrylates quaternary ammonium methacrylate monomers (UDMQAs) with different substituted alkyl chain length were synthesized, and their structures were confirmed by FTIR and 1H‐NMR spectra. The obtained UDMQAs were used to replace 2,2‐Bis[4‐(2‐hydroxy‐3‐methacryloyloxypropyl)‐phenyl]propane (Bis‐GMA) totally as base monomers of dental resin and mixed with Tri‐ethyleneglycol dimethacrylate (TEGDMA) at the mass ratio of 50/50. The properties of these prepared resins like antibacterial activity, double bond conversion (DC), polymerization shrinkage, flexural strength (FS), and modulus (FM), water sorption and sol fraction were investigated. The most commonly used dental resin Bis‐GMA/TEGDMA (50wt/50wt) was chosen as a reference. The results showed that UDMQAs could endow dental resin with antibacterial activity. Compared with Bis‐GMA‐based dental resin, UDMQAs‐based resin had the same or higher DC, lower polymerization shrinkage, lower flexural strength and modulus, and higher water sorption and sol fraction. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

18.
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