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1.
通过全氟壬烯氧基苯磺酸钠(C9F17OC6H4SO3Na,OBS)与四丁基溴化铵(TBAB)的复配,研究了OBS与TBAB复配体系的表面性能和润湿性能。在不同摩尔比下碳氟表面活性剂与季铵盐复配体系的临界胶束浓度(cmc)、最低表面张力(γcmc)、复配体系的总饱和吸附量(Γtm)和极限分子面积(Amin)的研究结果表明,在最佳等摩尔比时,体系的cmc和γcmc被降到最低,获得了最大总饱和吸附量(Γtm)(5.27 mol.cm-2)和最小的极限分子面积(Amin)(0.32 nm2),使其在水溶液中的表面性能增强。同时等摩尔比的复配体系,在大于0.10mmol.L-1的浓度区复配体系接触角较小,显示比较好的润湿性。  相似文献   

2.
全氟丁基磺酸钠与辛基三乙基溴化铵的相互作用   总被引:1,自引:0,他引:1  
通过测定辛基三乙基溴化铵(C8H17N(CH2CH3)3Br,C8NE)与全氟丁基磺酸钠(C4F9SO3Na,C4F)组成的不同混合比的碳氢-碳氟正负离子表面活性剂混合体系的表面张力,得到不同摩尔比时C8NEC4F体系的临界胶束浓度(cmc)、cmc处的表面张力(γcmc)、总饱和吸附量、不同表面张力时表面吸附层的组成,利用Gibbs-Duhem方程求得cmc处的胶团组成。 采用规则溶液理论计算了胶团中分子间相互作用参数(βm),并求得cmc以上的胶团组成。 实验表明,C8NEC4F复配体系的cmc远远小于单体系的cmc,这也体现在该体系的βm负值很大,胶团内分子相互作用很强。 但是C4F与C8NE复配后γcmc较C4F单体系的变化幅度不是特别大(γcmc降低2~4 mN/m),这是由于C8NEC4F碳链的不对称性导致部分C8NE的碳链在溶液表面弯曲而覆盖了C4F端基CF3基团。 表面吸附层中氟表面活性剂相对于本体溶液是富集的,即使对于C8NE大大过量的体系,表面吸附层组成也在等摩尔附近;对于C4F过量的体系,C4F在表面吸附层中的比例比溶液中的略高。 随着表面张力的降低,表面吸附层的组成相对更偏向于氟表面活性剂。 cmc处的胶团组成随着体系中C4F含量的增大偏向于形成显著富含C4F的胶团,对于C8NE大大过量的体系,胶团组成接近等摩尔。 cmc之后的胶团组成接近等摩尔,主要归因于此时静电相互作用占主导,这和溶液配制过程中发现复配体系超过cmc一定浓度后就易生成沉淀的现象是相符的。  相似文献   

3.
糖苷基季铵盐与十二烷基硫酸钠复配性能的研究   总被引:3,自引:0,他引:3  
研究了糖苷基季铵盐(CAPG)与十二烷基硫酸钠(K12)复配体系的稳定性、表面活性、泡沫性能和润湿性能.结果表明:CAPG与K12复配体系的稳定性好,并表现出很好的协同增效作用.当n(CAPG)∶ (K12)等于0.1∶ 1,0.3∶ 1,0.5∶ 1时,复配体系的临界胶束浓度(cmc)分别为0.081 mmol/L,0.065 mmol/L,0.054 mmol/L,大大低于单一组分的cmc,临界胶束浓度时的表面张力(γcmc)比单一组分略低,起泡力和泡沫稳定性均好于单一组分,润湿力比K12略低,但比CAPG好得多.  相似文献   

4.
十二烷基甜菜碱/十二烷基硫酸钠复配体系的表面活性   总被引:29,自引:0,他引:29  
研究了两性表面活性剂十二烷基甜菜碱(C12BE)和阴离子型表面活性剂十二烷基硫酸钠(SDS)复配体系的形成胶束能力,降低表面张力效率,降低表面张力能力三种增效作用.发现C12BE和SDS摩尔比为6 :4时增效作用最显著.并考察了盐、醇对复配体系表面活性的影响,结果表明,加盐能导致表面活性的提高,加醇的机理比较复杂,乙醇对复配体系表面活性影响不大,而正丁醇影响则比较显著.  相似文献   

5.
用表面张力法研究了β-环糊精与十一烷基酰胺甲酸钠(C11H23CONHCOONa,SF)两性表面活性剂在不同温度下的包结作用。结果表明:SF的表面张力值(β)及表观临界胶束浓度(cmc)加入β-CD后增加,β-CD浓度越大,γ和cmc增加越多,且SF的cmc与β-CD浓度存在线性关系,随温度的升高,两性表面活性剂的表面张力值降低,意味着它们的表面活性随温度升高而增强。利用表面张力测定了β-CD-SF体系在不同温度下的包结形成常数Ka,进而求得了包结过程的焓变和熵变,结果表明,该过程是焓和熵均有利的过程,进一步说明疏水作用是形成包结物最重要的的作用力之一。  相似文献   

6.
三联阳离子表面活性剂的合成及复配性能   总被引:2,自引:0,他引:2  
陈丹丹  许虎君  赵伟 《应用化学》2007,24(10):1211-1215
以环氧氯丙烷、叔胺、甘油为主要原料,水为溶剂,经过开环、季铵化反应,合成了新型三联季铵盐阳离子表面活性剂(Ⅲ-12-4),得率为86.9%。采用质谱和元素分析测试技术对产物结构进行表征,证明所得产物即为目标产物。通过采用DCA-315型表面张力及动态接触角分析仪对表面张力的测定研究了其与十二烷基硫酸钠(SDS)复配体系的表面化学性质,稳态荧光探针法考察了微极性变化,还得到了胶束聚集数。结果表明,复配体系与单一体系相比,具有更低的临界胶束浓度(cmc)和降低表面张力的效能,表现出协同效应。当n(Ⅲ-12-4)∶n(SDS)=3∶7时,复配体系的临界表面张力(γcmc)和临界胶束浓度分别为16.95mN/m和1.33×10-5mol/L,并且胶束聚集数只有SDS的1/6,混合胶束结构紧密,微极性降低。  相似文献   

7.
季铵盐二聚表面活性剂C12-s-C12·2Br(s=2、3、4、6)和非离子表面活性剂C12E10或C12E23在水溶液中生成混合胶团.其临界胶团总浓度cmcT值介于二元复配体系中各组分的临界胶团浓度cmc01和cmc02之间.当添加少量非离子型表面活性剂(在水溶液中的摩尔分数α2=0.1)时,混合胶团中C12E10或C12E23的摩尔分数均已超过0.35;随着溶液中非离子型表面活性剂含量的增大,混合胶团中逐渐以C12E10或C12E23成分为主.  相似文献   

8.
研究了十二烷基胺盐酸盐(DAC)和十二烷基聚氧乙烯硫酸钠(AES)复配体系的表面性质与胶束化行为.发现该体系在广泛的复配比例区间和温度区间内保持了极为优异的表面活性,测定了该体系的临界胶束浓度(cmc)与其对应的表面张力(γcmc)的具体值,并研究了温度、pH值和离子强度等环境因素对相关体系的影响.  相似文献   

9.
本文合成了3个氨基酸型表面活性剂:十二烷基甘氨酸钠(C12GlyNa)、十二烷基氨基丙二酸钠(C12MalNa2)和十二烷基谷氨酸钠(C12GluNa2),用表面张力法、荧光探针法及接触角测量,研究了它们的分子结构对表面活性、自聚集行为以及对方解石润湿性能的影响。结果表明,当增加一个羧基后,氨基酸型表面活性剂的临界胶团浓度(cmc)和最低表面张力(γ_(cmc))增大,饱和吸附量(Г_(max))和胶团聚集数减小,降低表面张力的效率(pC_(20))降低,但在方解石表面的接触角变化较小。与C12MalNa2相比,在两个羧基之间增加一个亚甲基的C12GluNa2,其最低表面张力(γ_(cmc))变化很小,但cmc和Г_(max)更小,A_(min)更大,在方解石表面的最大接触角增大,对方解石的润湿性能降低。  相似文献   

10.
甲酰胺与正负离子表面活性剂有序溶液的研究   总被引:2,自引:0,他引:2  
对羧酸钠与烷基三甲基溴化铵1:1混合体系的研究表明:常温下各体系在不同比例甲酰胺(FA)/水混合溶剂中,表面张力随浓度变化均有明显的转折点,显示了混合体系中胶团的存在.实验中发现随混合溶剂中FA比例增加,各体系的临界胶团浓度(cmc)增大.在较高温度下发现在甲酰胺中亦存在着因胶团形成而产生的表面张力-浓度对数(γ-logc)曲线的转折点,利用相分离模型对体系胶团热力学参数进行了计算.并探讨了FA对正负离子表面活性剂囊泡的影响.  相似文献   

11.
理想混合表面活性剂表面张力的计算公式及实验验证   总被引:1,自引:0,他引:1  
采用Newton迭代法, 给出了两种计算二组分表面活性剂理想混合体系表面张力的显函数简捷表达式, 并通过膦氧化物同系物, 季铵盐混合体系, 以及全氟辛酸铵和全氟壬酸铵混合系列表面张力的实验值和数值解对其精确性进行了验证. 结果表明, 两种迭代法都有很快的收敛速度, 表达式的相对误差都在1%之内.  相似文献   

12.
张兰辉  朱步瑶  赵国玺 《化学学报》1992,50(11):1041-1045
研究了四种氧杂氟表面活性及其与同电性直链碳氢表面活性剂混合体系的表面活性;考察了混合体系中的表面吸附和胶团形成现象.在吸附层中分子间有明显的互疏作用,在溶液中倾向于各自形成胶团.还讨论了反离子结合度不同对理想混合胶团的组成CMC的计算的影响,提出了一般的计算式,实验测得这些氧杂氟表面活性剂有较低的胶团反离子结合度.  相似文献   

13.
The interactions of bovine serum albumin (BSA) with the anionic surfactant sodium decylsulfonate (C10SO3), the cationic surfactant decyltriethylammonium bromide (C10NE) and equimolarly mixed cationic-anionic surfactants C10NE-C10SO3 were investigated by surface tension, viscosity, dynamic light scattering (DLS) and circular dichroism (CD). It was shown that the single ionic surfactant C10SO3 or C10NE has obvious interaction with BSA. The presence of C10SO3 or C10NE modified BSA structure. However, the equimolarly mixed cationic-anionic surfactants C10NE-C10SO3 showed very weak interactions with BSA. The surface tension-log concentration (gamma-logC) plot for the aqueous solutions of C10NE-C10SO3/BSA mixtures coincided with that of C10NE-C10SO3 solutions. Viscometry showed that there is no significant change in the rheological properties for the C10NE-C10SO3/BSA mixed solutions. DLS showed that BSA monomers and mixed aggregates of C10NE-C10SO3 existed in the C10NE-C10SO3/BSA mixed solutions. From CD spectra no obvious modification of BSA structure in the presence of C10NE-C10SO3 mixtures was observed. The weak interactions between BSA and C10NE-C10SO3 might be explained in terms of the very low critical micelle concentration (cmc) of C10NE-C10SO3 mixtures that made the concentration of ionic surfactant monomers much lower than that needed for inducing the modification of BSA structure. In other words, the very strong synergism between oppositely charged cationic and anionic surfactants makes the formation of cationic-anionic surfactant mixed aggregates in the bulk solution a more favorable process than binding to proteins.  相似文献   

14.
王慧敏  王仲妮  周武  吴同浩 《应用化学》2012,29(9):1053-1059
通过平衡表面张力的测定,研究了聚氧乙烯山梨醇酐脂肪酸酯(Tween)系列与聚氧乙烯(10)油基醚(Brij97)混合胶束形成的相互作用参数βm、分子交换能εm及热力学参数(ΔGom、ΔHom、ΔSom),并探讨了Tween系列分子结构、混合体系的组成及温度对胶束形成的影响。 研究表明,随着Tween碳链的增大,混合胶束中Tween的摩尔分数Xm1增大,协同效应增强;在Tween60/Brij97混合胶束中,ΔGom随着Tween60摩尔分数(α1)的增大而增大;在混合胶束形成中,α1≤0.33时,两组分表现出协同效应;在α1>0.33时,未表现出协同效应;温度对Tween60/Brij97混合体系的影响表明,温度升高,CMC和ΔGom减小,ΔHom和ΔSom增大,协同效应减弱。  相似文献   

15.
Interaction between binary surfactant mixtures containing anionic surfactants viz. sodium dodecyl sulphates (NaDS) and magnesium dodecyl sulphates (Mg(DS)2) and a nonionic surfactants viz. dodecyl dodecapolyethylene glycol ether (C12E12) and dodecyl pentadecapolyethylene glycol ether (C12E15) in water at different mole fractions (0–1) were studied by surface tension, viscometry and dynamic light scattering (DLS) methods. The composition of mixed micelles and the interaction parameter, β evaluated from the CMC data obtained by surface tension for different systems using Rubingh's theory were discussed. Activity coefficient (f1 and f2) of metal dodecyl sulphates (MDS)/C12Em (m = 12, 15) mixed surfactant systems were evaluated, which shows extent of ideality of individual surfactant in mixed system. The estimated interaction parameter indicates an overall attractive interaction in the mixed micelles, which is predominant for NaDS as compared to Mg(DS)2. Counter ion valency has specific effect on the mixed micelles, as Mg(DS)2 has less interaction with nonionic surfactants in comparison to NaDS due to strong condensation of counter ion. The stability factors for mixed micelles were also discussed by Maeda's approach, which was justified on the basis of steric factor due to difference in head group of nonionic surfactant. DLS measurements and viscosity data reveals the synergism in mixed micelles, showing typical viscosity trends and linearity in sizes were observed.  相似文献   

16.
利用二维晶格模型和相分离模型,由正规溶液理论首先推导出了二元表面活性剂形成混合胶束的分子交换能(ε~m)与混合胶束中组分A的超额化学位(μ^E~m~,~A)的关系式:μ^E~m~,~A=ε~m~gN~0(1-x~A)^2。然后导出ε~m与混合胶束中表面活性剂分子间的相互作用参数(β~m)的关系:ε~m=gRTβ~m/N~0。用该结论对皂荚素(GS)与十二烷基磺酸钠(C~1~2H~2~5SO~3Na)、十二烷基聚氧乙烯醚硫酸钠[C~1~2H~2~5(OC~2H~4)~3SO~4Na]、全氟辛酸钠(C~7F~1~5CO~2Na)、十二烷基脂肪醇聚氧乙烯(9)醚[C~1~2H~2~5(EO)~9OH]、辛基酚聚氧乙烯(10)醚[C~8H~1~7Ph(EO)~1~0OH]及十六烷基三甲基溴化铵(C~1~6H~3~3NMe~3Br)等表面活性剂混合体系的研究和计算表明:含皂荚素的二元表面活性剂形成的混合胶束,ε~m均为负值,表面活性剂分子间具有较强的协同效应。  相似文献   

17.
酯基Gemini型季铵盐表面活性剂与SDS的相互作用   总被引:1,自引:0,他引:1  
研究了酯基Gemini型季铵盐表面活性剂[Cm-1H2m-1COOCH2CH2(CH3)2N+(CH2)n+N(CH3)2CH2CH2OOCCm-1H2m-1]•2Br-(简称II-m-n, m=10, 12; n=3, 4, 6)与十二烷基硫酸钠(SDS)的复配体系的相互作用以及无机盐(NaBr)对复配体系表面活性的影响. 结果发现, 其复配体系具有显著的胶团化协同增效作用和降低表面张力的增效作用, 并且II-10-n与SDS的复配体系的增效作用具有等链长效应. II-m-n/SDS复配体系的胶团化协同增效作用随n增大而增强. 混合胶团中II-m-n与SDS的摩尔比均近似为1:1, 显示各复配体系的混合胶团均带电性, 因此NaBr的加入能增强复配体系的表面活性和促进混合胶团的形成.  相似文献   

18.
The interaction of anionic gemini surfactants with other surfactants (such as anionic, cationic, nonionic) was systematically overviewed, paying attention to synergism observed in various properties. These mixed systems were found to show remarkable synergism in micelle formation. The critical micelle formation values being lower than the individual gemini surfactants indicate that the mixed micellization is due to attractive interaction between the two components. Almost all combinations were discussed in terms of respective surface tension reduction effectiveness and surface tension reduction efficiency and aggregation number for evaluation of synergism.  相似文献   

19.
The Staudinger reaction of N(CH2CH2NR)3P [R = Me (1), Pr (2)] with 1 equiv of N3SO2C6H4Me-4 gave the ionic phosphazides [N(CH2CH2NR)3PN][SO2C6H4Me-4] [R = Me (3), R = Pr (5a)], and the same reaction of 2 with N3SO2C6H2Me3-2,4,6 gave the corresponding aryl sulfinite 5b. On the other hand, the reaction of 1 with 0.5 equiv of N3SO2Ar (Ar = C6H4Me-4) furnished the novel ionic phosphazide [[N(CH2CH2NMe)3P]2(mu-N3)][SO2Ar] (6). Data that shed light on the mechanistic pathway leading to 3 were obtained by low temperature 31P NMR spectroscopy. A crystal and molecular structure analysis of the phosphazide sulfonate [N(CH2CH2NMe)3PN3][SO3C6H4Me-4] (4), obtained by atmospheric oxidation of 3, indicated an ionic structure, the cationic part of which is stabilized by a transannular P-N bond. A crystal and molecular structure analysis of 6 also indicated an ionic structure in which the cation features two untransannulated N(CH2CH2NMe)3P cages bridged by an azido group in an eta 1: mu: eta 1 fashion. The reaction of P(NMe2)3 with N3SO2Ar (Ar = C6H4Me-4) in a 1:0.5 molar ratio furnished [[(Me2N)3P]2(mu-N3)][SO2-Ar] (11) in quantitative yield. On the other hand, the same reaction involving a 1:1 molar ratio of P(NMe2)3 and N3SO2Ar produced a mixture of 11, [(Me2N)3PN3][SO2Ar] (12), and the iminophosphorane (Me2N)3P=NSO2Ar (10). In contrast, the bicyclic tris(amino)phosphines MeC(CH2NMe)3P (7) and O=P(CH2NMe)3P (8) reacted with N3SO2-Ar (Ar = C6H4Me-4) to give the iminophosphorane MeC(CH2NMe)3P=NSO2Ar (14) (structured by X-ray means) and O=P(CH2NMe)3P=NSO2Ar (16) via the intermediate phosphazides MeC(CH2NMe)3PN3SO2Ar (13) and O=P(CH2NMe)3PN3SO2Ar (15), respectively. The variety of products obtained from the reactions of arylsulfonyl azides with proazaphosphatranes (1 and 2), acyclic P(NMe2)3, bicyclic tris(amino)phosphines 7 and 8 are rationalized in terms of steric and basicity variations among the phosphorus reagents.  相似文献   

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