系列磺丁基甜菜碱的表征及表面活性

用FT-IR、1H NMR和元素分析对自制的3种磺丁基甜菜碱(SBm-4)的结构进行了表征,研究了它们的表面性能、泡沫性能和乳化性能。 获得SB12-4的cmc为2.20×10-3 mol/L,γcmc为31.48 mN/m;SB14-4的cmc为2.80×10-4 mol/L,γcmc为29.68 mN/m;SB16-4的cmc为2.30×10-5 mol/L,γcmc为32.06 mN/m。 3种磺丁基甜菜碱的cmc值随着烷基链长增加逐渐减小,γcmc先减小后增加,三者的起泡性随浓度增加而增加,到一定值后保持不变;泡沫稳定性随浓度增加逐渐增强,起泡性随着温度的增加有缓慢增加趋势,泡沫稳定性随温度增加逐渐降低。 3种表面活性剂的乳化能力随浓度增加先增加后降低。     

十五烷基芳基磺酸钠溶液表面性质的影响因素研究

测定了自制的四种高纯度十五烷基间二甲苯磺酸钠在纯水溶液和0.0393 mol/L异丙醇溶液中的表面性质,结果表明,随芳基向碳链中间位置的移动,临界胶束浓度cmc增大,分子极限占有面积Amin增大,标准吸附自由能 变得更负,降低表面张力的效率pc20增强,饱和吸附量Γ_max降低,临界胶束浓度时的表面张力γ_cmc降低;且异丙醇的加入使磺酸钠溶液的临界胶束浓度显著降低。从分子结构的特点探讨了分子支化程度对表面性能的影响。     

乙醇/水混合溶剂中Gemini表面活性剂的表面性质

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.     

稳态荧光探针法测定三聚季铵盐表面活性剂的胶束聚集数

以芘为荧光探针, 十六烷基氯化吡啶(CPC)为猝灭剂, 以芘的饱和水溶液为溶剂配制表面活性剂溶液, 根据芘的荧光强度之比I1/I3随表面活性剂水溶液浓度的变化, 测定了三聚季铵盐表面活性剂CTTTA的cmc值, 测定值与表面张力法测定的cmc值一致；当猝灭剂CPC的浓度取0.1~0.3 mmol·L-1范围时, 用稳态荧光探针法测定了CTTTA的胶束聚集数. 实验数据表明, 表面活性剂溶液浓度为6~10倍cmc时, 胶束聚集数N随表面活性剂浓度增大而线性增大, 并用外推法得到CTTTA的临界胶束聚集数.     

阳离子和两性表面活性剂对石英表面润湿性的影响

利用座滴法研究了阳离子表面活性剂十六烷基醚羟丙基季铵盐(C16PC)和两性离子表面活性剂十六烷基醚羟丙基羧酸甜菜碱(C16PB)溶液在石英表面上的润湿性质, 考察了表面活性剂类型及浓度对接触角的影响趋势, 讨论了黏附张力和黏附功的变化规律. 研究发现, 两种表面活性剂在高能的石英表面的吸附造成石英-水的界面自由能(γsl)增大. C16PB通过弱相互作用随机吸附到石英表面, 其增大γsl的能力与降低表面张力(γ1g)的能力相当, 接触角(θ)随浓度变化不大. C16PC 随体相浓度增大能够在石英表面通过静电作用形成定向排列的单分子层, 而后在临界胶束浓度(cmc)附近形成双层结构, 接触角随浓度变化的趋势可分为4个区域, 并通过一个极大值.     

新型磺基甜菜碱/聚丙烯酰胺体系表面及界面性能

采用自制的新型磺基甜菜碱两性表面活性剂与相对分子质量2500万的聚丙烯酰胺进行复配,考察了不同温度和矿化度条件下,聚合物对复配溶液表面、界面性能的影响。 采用滴体积法测定了溶液的表面张力,结果表明,加入聚合物使溶液的临界胶束浓度增大,且复配溶液的表面张力大于单独表面活性剂溶液的表面张力。 当聚合物浓度一定,增大溶液矿化度时,体系表面张力增大。 用旋滴型界面张力仪测定了溶液的界面张力,结果表明,增大聚合物浓度,油水界面张力增大,增大溶液矿化度,油水界面张力有所升高。 聚合物质量浓度为1.5 g/L,表面活性剂质量浓度为0.3 g/L时,可使胜利油田孤岛原油和孤东原油的油水界面张力达到超低数量级（10-3 mN/m）。 用分水时间法测定了溶液的乳化性能,结果表明,聚合物浓度增大,分水时间延长,并考察了75、85和95 ℃条件下体系的乳化性能,温度越高,分水时间越短。     

多支链烷基苯磺酸钠水溶液的表面性质

用自制的四种高纯度多支链烷基苯磺酸钠,研究了支链结构对其表面性质的影响.结果表明,随支链烷基碳数增加,临界胶束浓度降低,标准吸附自由能DGadӨ更负;但是,饱和吸附量Γmax却随支链烷基碳数增加而减小,且临界胶束浓度时的表面张力γcmc随吸附量减小而降低,表现出与一般表面活性剂不同的变化趋势.从多支链烷基苯磺酸钠的分子结构特点,解释了随支链烷基碳数增加Γmax和γcmc的变化规律,探讨了分子的独占面积(as)对Γmax及γcmc的影响.     

N-酰基-L-丝氨酸钠表面活性剂的合成和胶束化热力学性质

以L-丝氨酸和长链酰氯为原料,合成了3种不同碳链长度（n=8,12,14）的N-酰基-L-丝氨酸。 并以1H NMR、ESI-MS和元素分析对3种目标产物进行了表征。 采用表面张力法研究了N-酰基-L-丝氨酸钠在298、308、318和328 K时水溶液中的聚集行为,确定了临界胶束浓度（cmc）、临界胶束浓度下的最低表面张力（γcmc）、表面饱和吸附量Γmax。 由cmc和温度的关系,应用相分离模型计算了胶束化热力学参数ΔGom、ΔHom和ΔSom。 结果表明,ΔGom＜0,ΔHom的绝对值比-TΔSom绝对值小的多,说明胶束化过程为熵驱动过程,随着温度的升高,胶束化过程是熵-焓补偿的过程。     

表面活性剂浓度对泡沫堆积高度的影响及参数分析

基于实验方法,研究了表面活性剂浓度及相关参数对泡沫堆积高度的影响.实验结果表明:减小表面张力,增大气体表观速率有利于提高泡沫堆积高度;在一定范围内增大黏度有利于提高泡沫堆积高度,但黏度过大时泡沫堆积高度反而减小;当表面活性剂浓度超过临界胶束浓度(cmc)后,胶团稳定泡沫的作用不明显;当表面活性剂浓度超过"临界作用浓度"后,泡沫堆积高度迅速增大.通过回归试验数据,分别获得不同表面活性剂浓度范围内的泡沫堆积高度公式.     

临界胶束浓度cmc与饱和吸附Γ′2∞的关系

关于临界胶束浓度cmc(critical micelle concentration)与饱和吸附Г’_(2∞)的关系,一般物理化学教材中描述为:“当表面活性剂(SAA)的浓度足够大时,溶液表面吸附达饱和,表面张力σ不再下降,此时溶液表面层内的表面活性剂分子定向排列而形成单分子膜,若再增     

Novel Cationic Gemini Surfactants Based on Piperazine: Synthesis,Surface Activity,and Foam Ability

A series of novel Gemini surfactants C_n-pi-C_n 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 (γ_cmc) 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.     

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。     

Comparative Analysis of the Properties of Tween‐20, Tween‐60, Tween‐80, Arlacel‐60, and Arlacel‐80

Foamability and foam stability, emulsifying power, surface tension, and interfacial tension were investigated for Tween‐20 (polyoxyethylene sorbitan monolaurate), Tween‐60 (polyoxyethylene sorbitan monostearate), Tween‐80 (polyoxyethylene sorbitan monooleate), Arlacel‐60 (Sorbitan stearate), and Arlacel‐80 (Sorbitan oleate). Among all the surfactants tested for their foaming power and foamabilty, Arlacel‐60 and Arlacel‐80 showed the best results; the foaming power and foamability was found to be 100%. The surfactants having foam stability more than 50% can be considered as metastable and those less than 50% are considered as low‐stability foams. In case of surface tension and interfacial tension property measurements, Arlacel‐80 showed the best results. At 1% surfactant concentration, the surface tension and interfacial tension of Arlacel‐80 was found to be 29.9 dynes/cm and 1.1 dynes/cm at 30°C ambient temperature. Also, Arlacel‐60 was found to exhibit the best emulsifying power among all the surfactants tested. At 30°C, the emulsifying property of Arlacel‐60 was 6 hours.     

Gemini型磺基琥珀酸酯钠表面活性剂的结构与性能的关系

以不同的醇为原料,合成了不同的Gemini型磺基琥珀酸酯钠阴离子表面活性剂,对它们的表面化学性能和应用性能进行了测定,并将其性质与其结构的关系进行关联。结果表明:其活性高于相应单基表面活性剂,且联结基、憎水链长度对其活性有影响。联结基长度增加,产物的临界胶束浓度(CMC)降低,对应的表面张力增加,其乳化性、起泡性、稳泡性、渗透力降低,增溶性提高;憎水链长度增加,CMC降低,对应的表面张力先减后增,其乳化性、稳泡性、增溶性提高,起泡性先增后减,渗透力减弱。     

Surface adsorption and micelle formation of surface active ionic liquids in aqueous solution

Aqueous solutions of three kinds of surface active ionic liquids composed of the 1-alkyl-3-methylimidazolium cation have been investigated by means of surface tension and electrical conductivity measurements at room temperature (298 K). The surface tension measurements provided a series of parameters, including critical micelle concentration (cmc), surface tension at the cmc (gammacmc), adsorption efficiency (pC20), and effectiveness of surface tension reduction (Picmc). In addition, with application of the Gibbs adsorption isotherm, maximum surface excess concentration (Gammamax) and minimum surface area/molecule (Amin) at the air-water interface were estimated. The effect of sodium halides, NaCl, NaBr, and NaI, on the surface activity was also investigated. It was found that both the pC20 and the Picmc were rather larger than those reported for traditional ionic surfactants and the cmc values were somewhat lower than those for typical cationic surfactants, alkyltrimethylammonium bromides, and comparable to typical anionic surfactants, sodium alkyl sulfates. These results demonstrate that the surface activity of long-chained imidazolium IL is somewhat superior to that of conventional ionic surfactants.     

评价表面活性剂溶液泡沫性能的方法—真球气泡法北大核心CSCD

通过真球气泡法测定了不同价数和浓度的无机盐体系下十二烷基硫酸钠(SDS)表面活性剂溶液的表面张力和表面扩展黏度;通过Ross-Miles法测定了相应同一溶液的发泡力和泡沫稳定性;结果表明:SDS溶液的表面张力值随着各种无机盐浓度的增加而减小至不变,此时的无机盐浓度作为相对浓度100%来考察时,发现临界胶束浓度(CMC)值与添加盐的种类无关,只随无机盐的相对浓度的增加而减少;即CMC值随着无机盐的相对浓度的增加从不含无机盐时的8.3 mmol/L均收敛至最小值3.0 mmol/L;表面张力值和对应的发泡力值呈负线性关系,由此推断表面张力值可以评价发泡力;表面扩展黏度值和对应的泡沫稳定性值呈正线性关系,由此推断表面扩展黏度可以评价泡沫稳定性;无机盐种类对SDS表面活性剂发泡力和泡沫稳定性的影响力随阳离子价数(Na^(+)、Cu^(2+)、Fe^(3+))增加而增加。     

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.     

Adsorption and Micellization Properties of Novel Heterodouble‐Chained N‐Acyltaurate Surfactants

A set of heterodouble‐chained N‐acyltaurate surfactants (abbreviated as m+nP‐T, where m and n were carbon numbers of alkyl chain; P was phenyl; T was taurate) were synthesized. The novel amphiphiles contained sodium taurine as hydrophilic moiety and two different hydrocarbon chains as hydrophobic moiety. One was a long alkyl chain, and the other had an aromatic residue. Their surface properties were determined by Wilhelmy‐plate method, and micellization properties were investigated by fluorescence spectra of extrinsic probe and intrinsic probe. It was found that these surfactants showed some aberrant properties. It was difficult to obtain the equilibrium surface tension and critical micelle concentration (cmc) for the surfactants with two long chains. Pyrene was solubilized in micelle at concentration above cmc, and the fluorescent intensity ratio of the first vibronic peak (373 nm) to the third vibronic peak (383 nm) of pyrene decreased gradually. The aggregation number N, characterized by quenching the phenoxyl residue with methyl viologen (MV²⁺) as the extrinsic quencher, gradually increased with increasing surfactant concentration. These indicated that more and more molecules packed in a micelle with increasing concentration.