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1.
New type of triazolium Gemini surfactants were synthesized by reaction of epichlorohydrine with long-chain fatty alcohols namely cetyl alcohol and oleyl alcohol furnishing product 2-(alkoxymethyl)oxirane followed by the their subsequent treatment with triazole resulting in the formation of 1-(1,2,4-triazole)-3-alokoxypropane-2-ol which on reaction with 1,6-dibromohexane resulted in the formation of triazolium-based cationic Gemini surfactant. Their formation was confirmed by IR spectroscopy. Surface tension values were used to determine the critical micelle concentration (CMC), minimum area per molecule (Amin) at air?water interface, Gibbs free energy of adsorption (ΔGads), the maximum surface excess concentration (Γmax), and other parameters. The inhibition behavior of dimeric surfactant on the corrosion of carbon steel (CS) in 1 N H2SO4 aqueous medium was studied at 30°C. Performance tests like dispersion capability, foaming power and stability, emulsifying power, and wetting ability were determined. The obtained results show that dispersion capability, foaming power, foaming stability, and emulsifying ability are very good. The wetting power of synthesized surfactants is quite better.  相似文献   

2.
以苯胺、环氧氯丙烷和十四烷基二甲基叔胺为原料,合成了含有苯环的阳离子Gemini型沥青乳化剂3,3'-苯基亚氨基-(二(2-羟基丙基-十四烷基二甲基)氯化铵)(G-T)。 采用傅里叶红外光谱(FT-IR)、质谱(MS)和核磁共振谱(1H NMR)对产物进行了结构表征。 研究了其Krafft点、乳化性能和乳化沥青时的相关性能,并测定了25~40 ℃的临界胶束浓度(cmc)、平衡表面张力(γcmc)及计算了相应的热力学函数。 结果表明,G-T的Krafft点低于0 ℃,乳化分水时间为309 s。 25 ℃时,cmc为1.269×10-3 mol/L,γcmc为38.33 mN/m。 随着温度的升高,cmc增大、γcmc减小、饱和吸附量(Γmax)减小、极限占有面积(Amin)增大。 乳化沥青测试表明,G-T拌和时间为255 s,是慢裂型沥青乳化剂。 所制备的乳化沥青满足微表处技术规范。  相似文献   

3.
The synthesis of surfactants derivatives of new two series of cationic gemini surfactants containing ethane or benzene as a spacer are described. The prepared compounds were analyzed using standard tools of analysis, elemental analysis, FTIR measurements, and H1 NMR spectra. The influence of dimerization and of the spacer group were examined in order to establish structure-property relationships. The critical micelle concentration (CMC) of each series has been determined using equilibrium surface tension measurements. Furthermore, air/water interface parameter including effectiveness (Πcmc), efficiency (P20), maximum surface excess (τmax), and minimum surface area (Amin) have been also derived using Gibbs adsorption equation at 25°C. Standard free energies of micelleization were calculated and biological activities were examined. The results revealed that the dimeric surfactants have a good effect on the biological activities.  相似文献   

4.
Four gemini cationic surfactants {N,N‘-di[2-(lauryldimethylamino)acetyl]polymethylenediamine dichloride, LAA-s-LAA, s = 2,3,4,6 } were synthesized by using four bis (a-chloroacetamide)s and N, N-dimethyl-laurylamine, respectively. The molecular structures were characterized by means of IR, ^1H NMR. ^13C NMR and MS, and the behavior of their aqueous solutions was studied. The critical micell concentrations (CMC) of LAA-s-LAA were one order of magnitude lower than that of dodecyltrimethyl ammonium chloride (DTAC). With the change of the length of spacer chain(s), their CMC values change, and CMC reaches the top value at s=4.  相似文献   

5.
通过对Gemini表面活性剂12-s-12 (Et)(s=4, 6, 8, 10, 12)体系在乙醇/水混合溶剂中的表面张力曲线的测定, 对该体系的表面性质进行了研究. 发现随乙醇/水比例变化, Gemini各种表面化学性质, 如临界胶束浓度(cmc)、表面张力(γcmc)、饱和吸附量(Γmax)和最小分子占有面积(Amin)等的变化规律. 拓展了Gemini表面活性剂在混合溶剂中表面吸附的研究.  相似文献   

6.
A series of Gemini borate surfactants were synthesized based on glucose molecule. Their chemical structures were confirmed using 1H-NMR,13C nuclear magnetic resonance (NMR), and mass spectroscopy. The surface activities of these Gemini amphiphiles were measured, including surface tension (γ), critical micelle concentration (CMC), effectiveness (IIcmc), efficiency (pC20), maximum surface excess (Γmax), and minimum surface area (Amin) at different temperatures 25, 35, and 45°C either in pure water or in water–ethanol mixture (10%). Also, thermodynamic data including free energy, entropy, and enthalpy changes (ΔS, TΔS, ΔH) for adsorption at the air–water interface and also for micellization in surfactant solutions were calculated.  相似文献   

7.
以N,N-二甲基-1,3-丙二胺、固体光气、溴代烷为原料合成了三种新型含脲基双子表面活性剂(LY-12、LY-14、LY-16),并通过1H NMR、ESI-MS和FT-IR表征了结构。测定了其Krafft点、乳化性能、起泡性能;通过测定表面张力γcmc以及不同温度下的临界胶束浓度(CMC)计算表面活性参数(Γmax、Amin、pc20)与热力学参数(ΔGmθ、ΔHmθ、ΔSmθ)。结果表明,LY-12、LY-14的Krafft点低于0℃,LY-16的Krafft点低于10℃;LY-12、LY-14、LY-16的乳化时间分别为173、275和338 s;LY-12的起泡性显著优于LY-14和LY-16;三种表面活性剂的表面张力γcmc分别为38. 77、37. 42和36. 59 m N/m;298. 15K条件下,其CMC值分别为0. 19、0. 15、0. 13 mmol/L。表面活性参数与热力学参数计算表明,三种表面活性剂均具有高的表面活性且胶束的形成是熵驱动的自发放热过程。  相似文献   

8.
Gemini surfactants, which contain two hydrophilic groups and two hydrophobic groups in the molecule, are considered as a new generation of surfactants. These surfactants are about 3 orders of magnitude more efficient at reducing surface tension and more than 2 orders of magnitude more efficient at forming micelles than conventional surfactants1. During recent years, many gemini surfactants have been synthesized, and a considerable number of investigations have been reported on their unusua…  相似文献   

9.
New pyridinium gemini surfactants have been synthesized by esterification of renewable fatty acids with mercaptoethanol furnishing respective esters (mercaptomethyl decanoate, mercaptomethyl dodecanoate, mercaptomethyl tetradecanoate, mercaptomethyl hexadecanoate) followed by their subsequent treatment with 4-dimethyl amino pyridine resulting in the formation of title gemini surfactants: 1-(5-(decanoyloxy)-2-hydroxypentyl)-4-((5-(decanoyloxy)-2-hydroxypentyl)dimethyl ammonio)pyridin-1-ium chloride (9), 1-(5-(dodecanoyloxy)-2-hydroxypentyl)-4-((5-(dodecanoyloxy)-2-hydroxypentyl)dimethyl ammonio)pyridin-1-ium chloride (10), 1-(5-(tetradecanoyloxy)-2-hydroxypentyl)-4-((5-(tetradecanoyloxy)-2-hydroxypentyl)dimethyl ammonio)pyridin-1-ium chloride (11), and 1-(5-(hexadecanoyloxy)-2-hydroxypentyl)-4-((5-(hexadecanoyloxy)-2-hydroxypentyl)dimethyl ammonio)pyridin-1-ium chloride (12). Their identifications are based on infrared, 1H NMR, 13C NMR, distortionless enhanced polarization transfer, co-relational spectroscopy (COSY), and mass spectral studies. Their surface active properties are also evaluated on the basis of surface tension and conductivity measurements. Thermal stability of these long chain cationic gemini surfactants have been measured by thermal gravimetric analysis under nitrogen atmosphere.  相似文献   

10.
季铵盐阳离子型双子表面活性剂的合成及其表面活性   总被引:2,自引:2,他引:0  
以二甲基长链烷基叔胺和1,5-二溴戊烷为起始原料合成了系列不同疏水烷基长度的阳离子型双子表面活性剂m-5-m(m=8, 12, 16).对其表面活性进行了初步研究,结果表明:所合成的系列产物都具有较好的表面活性,其中16-5-16具有最低的临界胶束浓度(CMC 0.289 mmol·L-1);随着疏水烷基链的增长,表面活性剂的CMC显著降低.对应的表面张力(γCMC)则随m的增加先降低,后增高,当疏水链为12个碳时为最低值;8-5-8的表面活性最差.  相似文献   

11.
A series of novel cationic gemini surfactants, p-[C n H2n+1N+(CH3)2CH2CH(OH)CH2O]2C6H4·2Cl? [A(n = 12), B(n = 14) and C(n = 16)], containing a spacer group with two flexible and hydrophilic groups (2-hydroxy-1,3-propylene) on both sides of a rigid and hydrophobic group (1,4-dioxyphenylene) has been synthesized by the reaction of hydroquinone diglycidyl ether with N,N-dimethylalkylamine and N,N-dimethylalkylamine hydrochloride. Their surface-active properties have been investigated by surface tension measurement. The critical micelle concentration (cmc) values of the synthesized cationic gemini surfactants are one order of magnitude lower than those of their corresponding monomeric surfactants (C n H2n + 1N+(CH3)3·Cl?). Both the cmc and surface tension at the cmc (γcmc) of A are lower than those of p-[C12H25N+(CH3)2CH2]2C6H4·2Cl? (D). The novel cationic gemini surfactants A and B also show good foaming properties.  相似文献   

12.
Gemini surfactants, containing several hydrophilic and hydrophobic groups in the molecules, are considered as a new generation of surfactants. It is extensively used in both material science and biotechnology. Bola-amphiphiles generally contain two ionic …  相似文献   

13.
A novel class of organosilicon quaternary gemini surfactants alkanediyl-α, ω-bis(methyl-dimethoxy-silopropyl-diethyl ammonium bromide) was synthesized with N,N-diethyl-aminopropyl-methyl-dimethoxysilane and α, ω-dibromoalkane as the raw materials, where the N,N-diethyl-aminopropyl-methyl-dimethoxysilane was synthesized by reacting diethylamine with γ-chloropropylmethyldimethoxysilane. The effects of various solvents on the conversion rate of the reaction and on purification of surfactants were investigated. The structures of the organosilicon quaternary ammonium gemini surfactants were determined by means of 1H NMR and elemental analysis. The properties of aqueous solution were measured with electrical conductivity and viscosity methods.  相似文献   

14.
以2,2-双(溴甲基)-1,3-丙二醇为连接基合成了新型的连接基为枝状的Gemini咪唑表面活性剂2,4-二(溴化-3-烷基咪唑)-1,3-丙二醇([Cn-P-Cnim]Br2,n=10,12,14).产物经核磁共振氢谱(1H NMR)、红外(IR)光谱和元素分析等进行了分析,证明所得产物即为目标产物.通过表面张力法和电导法测量其表面活性并计算胶束形成热力学参数(ΔG m—0,ΔH m—0,ΔS m—0).结果表明,25℃时3种表面活性剂均具有很高的表面活性,胶束的形成是自发的熵驱动过程.  相似文献   

15.
A series of novel Gemini surfactants Cn-pi-Cn with piperazine moiety as spacer was synthesized and characterized by IR, 1H NMR, and mass spectra. Their surface activities were evaluated by surface tension, electrical conductivity, and steady-state fluorescence. The obtained results indicated that the synthesized Gemini surfactants exhibited lower critical micelle concentration (cmc) and surface tension (γcmc) compared with traditional surfactants. The steady-state fluorescence measurement and electrical conductivity were recorded to demonstrate the accuracy of cmc values. In addition, the micellization was evaluated using conductivity measurement in the temperature range of 298–308 K. The foamability and foam stability of these Gemini surfactants were also examined. In which, the Gemini surfactant with the shortest chain (C12) showed the best foamability but the poorest foam stability. Hydrophile–lipophile balance and emulsifying ability were studied and a comparatively poor emulsifying ability displayed.  相似文献   

16.
本文合成了含酰胺基团和不含酰胺基团的两类Gemini阳离子表面活性剂,测定了其表面活性参数,研究了酰胺基团对表面活性剂的表面活性和聚集行为的影响。结果表明,酰胺基团提高了Gemini阳离子表面活性剂的临界胶团浓度,降低了胶团聚集数,增强了胶团微极性,增大了表面活性剂的饱和吸附量。  相似文献   

17.
Gemini表面活性剂是一类高效的新型表面活性剂,而醇是工业界和日化领域最常采用的表面活性剂助剂,因此研究不同结构的醇对Gemini表面活性剂表面活性和胶束化行为的影响规律和机理对于促进Gemini表面活性剂的发展和实际应用具有重要意义.利用表面张力、电导、等温滴定微量热,低温透射电镜和核磁共振研究了直链醇1-戊醇和具有相同主链的支链醇2-己醇与3-庚醇对具有不同长度连接基团阳离子季铵盐型Gemini表面活性剂C12CSC12Br2S=2,4,6,8,10,12)的表面活性和胶束化行为的影响,结果发现,支链醇能够显著影响表面活性剂在气/液界面的排布,使得C20 (使溶剂的表面张力降低20 mN/m所需的表面活性剂浓度)和γCMC (CMC时表面张力值)随醇支化度的增加而显著降低,而支链醇对表面活性剂在溶液中的临界胶束浓度以及胶束的尺寸和形貌均没有明显影响,同时这些醇对Gemini表面活性剂的影响与连接基团的长度相关.阐述了上述结果产生的机理,将有助于指导如何选择合适结构的醇助剂去调控Gemini表面活性剂的表面和溶液性质.  相似文献   

18.
Gemini surfactants contain two hydrophilic and two hydrophobic groups connected by a linkage close to the hydrophilic groups. Gemini surfactants have lower critical micelle concentration, higher surface activity, greater efficiency in decreasing the surface tension of water and the interfacial tension between water and oil, and better water solubility than conventional surfactants. Gemini surfactants are widely used as sterilizing, bacteriostatic, anti-foaming, and drug release agents in various enterprises including food production and industrial cleaning. They, therefore, play a very important social, economic, and industrial role. This paper briefly summarizes gemini surfactant development, structure, self-assembly, activity, classification, and characteristics, as well as focuses on the antibacterial mechanisms of these compounds. It is expected that the antibacterial properties of gemini surfactants may help slow the spread of the novel coronavirus (2019-nCoV).  相似文献   

19.
系列阳离子双子表面活性剂的合成及其表面活性的研究   总被引:10,自引:0,他引:10  
孙玉海  董宏伟  冯玉军  陈志 《化学学报》2006,64(18):1925-1928
合成了一系列新型的阳离子双子表面活性剂二溴化-N,N'-二(二甲基烷基)乙二铵(12-2-m', m'=4, 8, 12, 16), 初步研究了其水溶液的表面活性和电导率性质. 结果表明, 此类表面活性剂的表面活性与所含疏水尾基的碳数密切相关.  相似文献   

20.
磺酸盐型Gemini表面活性剂合成研究进展   总被引:1,自引:1,他引:1  
周明  赵金洲  刘建勋  杨燕 《应用化学》2011,28(8):855-863
磺酸盐型Gimini表面活性剂是一类新型的阴离子表面活性剂,它由联结基团通过化学键将2个或多个单体磺酸盐型表面活性剂连接在一起,由此产生高表界面活性,低临界胶束浓度值,增强了洗涤能力,与传统的阴离子表面活性剂有较好的复配性,奇异的流变特性和良好的抗盐性等一系列的性质,从而具有广泛的应用前景。 本文以原料来源不同分类,综述了一系列磺酸盐型Gemini表面活性剂的合成方法,展望了合成磺酸盐型Gemini表面活性剂的研究方向。  相似文献   

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