Micellization and Effect of Salt Behavior on Meristyl Alcohol Based Bis-Sulfosuccinate Gemini Surfactants in Aqueous Solutions

A series of bis-sulfosuccinate anionic gemini surfactants were synthesized from meristyl alcohol (BSGSMA_1,4; BSGSMA_1,6, and BSGSMA_1,8) containing 4, 6, and 8 methylene chains as different flexible spacer lengths. The chemical structures of synthesized geminis were confirmed by using spectroscopic analytical techniques, viz., elemental analysis, Fourier transform infrared spectroscopy (FTIR), and nuclear magnetic resonance spectroscopy(NMR). Investigations were carried out to examine the effect of different spacer length and different salts (organic and inorganic) on surface and fluorescence properties of prepared gemini surfactants. The results of surface properties shown that surface tension at CMC (?_CMC) and critical micelle concentration (CMC) were reduced and pC₂₀ value was enhanced with increased spacer length. Fluorescence investigations were also revealed the significance of longer spacer with the concluded remarks of higher aggregation number and reduced micropolarity for BSGSMA_1,8 having elongated flexible spacer. The results of salts studies had shown the better results for organic salts as compared to inorganic salts.     

新型孪尾Gemini两性离子表面活性剂应用性能

分别采用改进的Ross-Miles法及分水时间法,对3种新型孪尾Gemini两性离子表面活性剂(C8C8L3Sz、C8C8L4Sz和C10C8L3Sz)的泡沫性能及乳化性能进行了研究,并考察了表面活性剂浓度、分子结构和温度等对其的影响。 结果表明,该系列表面活性剂具有较好的泡沫性能,且随其浓度的增加,泡沫最大高度和半衰期均存在一个稳定值,疏水链越长,其起泡性能越差,泡沫稳定性越好;温度升高,起泡性能变好,泡沫稳定性变差;当表面活性剂浓度一定时,体系中加入低浓度的短链醇及无机盐均能提高泡沫的稳定性;C8C8L3Sz、C8C8L4Sz和C10C8L3Sz作乳化剂的最适宜的用量分别为6×10-4、6×10-4和4×10-4 mol/L,疏水基越长,乳化性能越好,而连接基对其影响较小;温度升高,乳化性能变差;当油相烷烃碳数相同时,环烷烃要比直连烷烃更易达到最佳乳化效果,但二者的乳状液稳定时间相当;对于油相烷烃碳数不同时,烷烃的碳链越长,乳状液的稳定性越差,乳化效果越不好。     

ESR Studies on the Micellization Behaviors of a Series of Novel Asymmetric Gemini Surfactants

ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｒｅｃｅｎｔｙｅａｒｓ ,ｂｉｓ(ｑｕａｔｅｒｎａｒｙａｍｍｏｎｉｕｍ)ｓｕｒｆａｃ ｔａｎｔｓｏｒｇｅｍｉｎｉｓｕｒｆａｃｔａｎｔｓ ,ｉｎｗｈｉｃｈｔｗｏｃａｔｉｏｎｉｃｓｕｒｆａｃ ｔａｎｔｍｏｉｅｔｉｅｓａｒｅｃｏｎｎｅｃｔｅｄｗｉｔｈｔｈｅａｍｍｏｎｉｕｍｈｅａｄｇｒｏｕｐｂｙａｐｌｏｙｍｅｔｈｙｌｅｎｅｃｈａｉｎ ,ｎａｍｅｌｙ ,ａｓｐａｃｅｒｈａｖｅｂｅｃｏｍｅｏｆｉｎｔｅｒｅｓｔｄｕｅｔｏｔｈｅｉｒｅｘｃｅｐｔｉｏｎａｌｓｕｒｆａｃｅａｃｔｉｖｉｔｙａｎｄｒｅｍ…     

羧酸盐二聚表面活性剂的合成

利用α-溴代月桂酸甲酯与二酚通过Williamson醚化得到二酯,再经皂化得羧酸盐二聚表面活性剂,其结构经1^H NMR,IR和元素分析确认。     

Salt Effect,Surface, and Aggregation Properties of Binary Surfactant Mixtures of a Nonionic Gemini Surfactant (HBA(EO)80) with Anionic Surfactants

Nonionic gemini surfactants HBA(EO)₈₀ were synthesized and characterized by means of surface tension measurements. CMCs of two mixed system, nonionic gemini mixed with anionic gemini (HBA(EO)₈₀/C11pPHCNa) and nonionic gemini mixed with anionic monomeric (HBA(EO)₈₀/SL) and the effect of salt on the two mixed system were investigated. Freeze-fracture transmission electron microscopy and scanning electron microscopy were used to investigate the mixed aggregates' morphologies. The results show that large spherical aggregates were formed in the mixed solution, which trend to transfer into micelles with the increases of the salt concentration.     

Mixing Behavior of Conventional and Gemini Cationic Surfactants

Micellization behavior of cationic monomeric surfactants, hexadecyltrimethylammonium bromide (CTAB), cetylpyridinium bromide (CPB), cetylpyridinium chloride (CPC), tetradecyltrimethylammonium bromide (TTAB), and dimeric (gemini) cationic surfactant pentamethylene‐1, 5‐bis(hexadecyldimethylammonium bromide) with formula C₁₆H₃₃(CH₃)₂N⁺(CH₂)₅N⁺(CH₃)₂C₁₆H₃₃ · 2Br^?, abbreviated as 16‐5‐16, in mixed states (binary) have been studied by conductivity. The micellar compositions, activities of the components, and their mutual interactions have been estimated from Rubingh's theory. The mixtures show nonideal behavior with favorable interactions.     

Antimicrobial Activity of Gemini Surfactants with Ether Group in the Spacer Part

Due to their large possibility of the structure modification, alkylammonium gemini surfactants are a rapidly growing class of compounds. They exhibit significant surface, aggregation and antimicrobial properties. Due to the fact that, in order to achieve the desired utility effect, the minimal concentration of compounds are used, they are in line with the principle of greenolution (green evolution) in chemistry. In this study, we present innovative synthesis of the homologous series of gemini surfactants modified at the spacer by the ether group, i.e., 3-oxa-1,5-pentane-bis(N-alkyl-N,N-dimethylammonium bromides). The critical micelle concentrations were determined. The minimal inhibitory concentrations of the synthesized compounds were determined against bacteria Escherichia coli ATCC 10536 and Staphylococcus aureus ATCC 6538; yeast Candida albicans ATCC 10231; and molds Aspergillus niger ATCC 16401 and Penicillium chrysogenum ATCC 60739. We also investigated the relationship between antimicrobial activity and alkyl chain length or the nature of the spacer. The obtained results indicate that the synthesized compounds are effective microbicides with a broad spectrum of biocidal activity.     

Synthesis,Characterization, and Surface Properties of Cationic Gemini Surfactants

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.     

甘氨酸酯衍生物双子季铵盐表面活性剂

双子表面活性剂;合成;甘氨酸酯衍生物双子季铵盐表面活性剂     

Synthesis and Surface Properties Activity of Novel Monoester Triethanolamine-Based Cationic Gemini Surfactants

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 (Π_cmc), efficiency (P20), maximum surface excess (τ_max), and minimum surface area (A_min) 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.     

Synthesis and Applications of Alkylbenzene Sulfonate Gemini Surfactants

A series of anionic Gemini surfactants with the same structure except for the spacer and side chain length of the alkylbenzene sulfonate were synthesized based on dodecyl benzene and toluene. The structures of the compounds were confirmed by infrared and nuclear magnetic resonance spectroscopy, and elemental analyses. The effect of spacer and side chain length on the interfacial tension of Gemini surfactant solution was investigated by comparison of the critical micelle concentration (cmc) of the surfactants in aqueous solution using the drop volume method, and the surface tension at the cmc (γcmc). The Gemini surfactant with the best properties was used as emulsifier in emulsion polymerization of methyl methacrylate, and its foam stability was also determined.     

羧酸盐双子表面活性剂的合成及性能

为筛选环境友好的新型双子表面活性剂,以水杨酸为原料设计合成了5个羧酸盐型双子表面活性剂EODPN1-EODPN5[2,2'-(1,2-CH₂CH₂-二-O-)-二-(4-C_nH_2n+1COPhCOONa),n=5,7,9,11和13],并通过核磁共振波谱仪(NMR)和傅里叶变换红外光谱仪(FT-IR)等对目标产物进行了结构表征。 探究了EODPN作为表面活性剂的性能,并利用Gibbs表面吸附方程,通过理论计算得到相关热力学参数,结果表明,目标分子具有优异的表面活性,临界胶束浓度(CMC)值低(最低达0.4 mmol/L),表面张力性能优良(最低达29.74 mN/m),单位面积表面吸附量(Γ)高(最高达3.37×10^-6 mol/m²)。 通过改变疏水基烷基碳链的长度,优化了EODPN的表面活性和自组装能力,筛选出EODPN4为最佳的表面活性剂。 借助EODPN4能与铜离子稳定结合,实现了表面活性剂含量的检测。     

Synthesis and Evaluation of Surface Activity of Gemini Borate Surfactants Based on Glucose Moiety

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 (II_cmc), efficiency (pC₂₀), maximum surface excess (Γ_max), and minimum surface area (A_min) 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.     

Synthesis and Surface Properties of Novel N-Alkyl Quinoline-Based Cationic Gemini Surfactants

Two series of cationic dimeric (gemini) surfactants are prepared with respect to key surfactants properties, such as surface activity and solubilization. The influence of both the dimerization and the spacer group is examined in order to establish structure-property relationships. The surface tension and critical micelle concentration can be markedly reduced compared to the monomeric surfactants in the pure state. The critical micelle concentration (cmc) of each series has been determined using equilibrium surface tension measurements. Furthermore, air/water interface parameters including effectiveness (π_cmc), efficiency (P_C20), maximum surface excess (Γ _max ), and minimum surface area (A _min ) have been also derived using Gibb's adsorption equation at 25°C. Standard free energies of micellization and adsorption were calculated. Solubilization behaviors of the synthesized surfactants were measured towards paraffin oil as solubilized material using light transmission technique.     

Interaction of Novel Anionic Gemini Surfactants with Dodecyl Sodium Sulfate in Aqueous NaCl Medium and the Performance of Their Mixtures

The interaction in two mixtures of two novel anionic gemini surfactants, sodium 2,2′-(6,6′-(ethane-1,2-diylbis(azanediyl)bis(4-(hexylamino)-1,3,5-triazine-6,2-diyl)bis(azanediyl)diethanesulfonate (C₆-2-C₆) and sodium 2,2′-(6,6′-(ethane-1,2-diylbis(azanediyl)bis(4-(octylamino)-1,3,5-triazine-6,2-diyl) bis(azanediyl) diethanesulfonate (C₈-2-C₈), and conventional anionic surfactants, sodium dodecyl sulfate (SDS), have been investigated in 0.1 M NaCl aqueous solutions. The mixed systems are C₆-2-C₆/SDS and C₈-2-C₈/SDS, and the mole factions (α_G) of geminis are 0.1, 0.3, 0.5, 0.7, and 0.9, respectively. Mixtures of both C₆-2-C₆/SDS and C₈-2-C₈/SDS exhibit synergism in surface tension reduction efficiency and mixed micelle formation. But, all mixtures except C₆-2-C₆/SDS (α_G = 0.7), C₆-2-C₆/SDS (α_G = 0.9), and C₈-2-C₈/SDS (α_G = 0.1) don't exhibit synergism in surface tension reduction effectiveness. The performances, such as wetting, emulsification, and dispersion were measured and the results showed all mixtures posses application properties.     

Novel Piperazine-based Gemini and Bola Surfactants

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 …     

Synthesis and Properties of a Sulfonic Acid-Containing Gemini Surfactant

A novel sulfonic acid-containing gemini surfactant, 6,6′-(butane-1,4-diylbis(oxy)) bis(3-nonylbenzenesulfonic acid), 9BA-4-9BA, was synthesized in high purity and high yield using a facile preparation pathway, and characterized by FTIR, ¹H NMR, and elemental analysis. The content of two sulfonic acid groups was measured by the acid-base titration. DSC and TGA were used to reveal the thermal properties and the product purity. The surface properties of 9BA-4-9BA were evaluated by equilibrium surface tension measurement. It shows that its CMC was 0.65 mmol/L, while the C₂₀ of 0.018 mmol/L was above two orders of magnitude lower than that of traditional monomeric surfactants such as SDS and SDBS, indicating excellent efficiency of micelle formation and reduced surface tension.     

新型脲基双子表面活性剂的合成及其性能

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。     

Promoting Efficacy and Environmental Safety of Pesticide Synergists via Non-Ionic Gemini Surfactants with Short Fluorocarbon Chains

Improving the utilization rate of pesticides is key to achieve a reduction and synergism, and adding appropriate surfactant to pesticide preparation is an effective way to improve pesticide utilization. Fluorinated surfactants have excellent surface activity, thermal and chemical stability, but long-chain linear perfluoroalkyl derivatives are highly toxic, obvious persistence and high bioaccumulation in the environment. Therefore, new strategies for designing fluorinated surfactants which combine excellent surface activity and environmental safety would be useful. In this study, four non-ionic gemini surfactants with short fluorocarbon chains were synthesized. The surface activities of the resulting surfactants were assessed on the basis of equilibrium surface tension, dynamic surface tension, and contact angle. Compared with their monomeric counterparts, the gemini surfactants had markedly lower critical micelle concentrations and higher diffusivities, as well as better wetting abilities. We selected a single-chain surfactant and a gemini surfactant with good surface activities as synergists for the glyphosate water agent. Both surfactants clearly improved the efficacy of the herbicide, but the gemini surfactant had a significantly greater effect than the single-chain surfactant. An acute toxicity test indicated that the gemini surfactant showed slight toxicity to rats.