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1.
A novel class of organosilicon gemini quaternary ammonium surfactant alkyl‐α, ω‐bis(diethyl‐methyl‐dimethoxy‐silopropyl ammonium bromide) (α, ω = 1,4; 1,6; 1,8) was synthesized and characterized by 1H‐nuclear magnetic resonance (NMR) and elemental analysis. It is found that the quaternization reaction has two steps: first single quaternization and then double quaternization. The effect of solvent on convert ratio has the following sequence: polar aprotic solvents > polar protic solvents > aromatic solvents. The electrical conductivity of aqueous solution was measured at 20, 25, 30 and 35 °C, and the thermodynamic properties of , and were calculated according to the mass action model and Gibbs equation. It is shown that the enthalpy driven and entropy driven are almost equal in the micellization of [SiC3‐4‐SiC3]Br2 and [SiC3‐6‐SiC3]Br2, but in the micellization of [SiC3‐8‐SiC3]Br2, the enthalpic contribution becomes significant and the effect of thermal is greater than the degree of order in the micellization.  相似文献   

2.
Dodecyl isopropylolamine has been synthesized on the basis of dodecylamine and propylene oxide. The structure of dodecyl isopropanolamine has been determined by X‐ray diffraction, elemental analysis, IR‐ and NMR‐spectroscopic methods. Ionic surfactants have been synthesized by interaction of dodecyl isopropylolamine with various acids (HCl, HBr, acetic and propionic) and alkyl halides (methyl iodide, ethyl bromide and n‐propyl bromide). Colloidal‐chemical parameters, petroleum‐collecting and petroleum dispersing capacities of the synthesized cationic surfactants have been studied.  相似文献   

3.
Novel dicephalic surfactants containing a quaternary ammonium and a guanidine group were synthesized, and the effect of the alkyl chain length on micellization and antimicrobial activity were investigated. Surface tension and conductivity were applied to study the self-aggregation of the amphiphilic molecule in aqueous solution. The results indicated that these compounds reduce the surface tension to a level of 30–36 mN/m at the air/water interface and that there is a characteristic chain length dependence of the micellization process of surfactants. The antimicrobial activity was evaluated against Gram-negative, Gram-positive bacteria and fungi, indicating strong antibacterial activity against tested strains.  相似文献   

4.
Two new classes of gemini cationic surfactants—hexanediyl-1,6-bis[(isopropylol) alkylammonium] dibromide {in the abbreviation form: CnC6Cn[iPr-OH] and CnC6Cn[iPr-OH]2; alkyl: CnH2n + 1 with n = 9, 10, 12 and 14}—have been synthesized by interaction of alkyl bromides with N,N′-di-(isopropylol)-1,6-diaminohexane and N,N,N′,N′-tetra-(isopropylol)-1,6-diaminohexane. The surface tension, electrical conductivity, and dynamic light scattering (DLS) techniques were used to investigate the aggregation properties of the gemini cationic surfactants in aqueous solution. The formation of critical aggregates at two concentrations in an aqueous solution from obtained gemini cationic surfactants were determined via the tensiometric method. Thus, these gemini cationic surfactants start to form aggregates at concentrations well below their critical micelle concentrations (CMC). The surface properties and the binding degree (β) of the opposite ion were tested against the length of the surfactant hydrocarbon chain and the number of the isopropylol groups in the head group. By applying the DLS technique, it was explored that how the number of isopropylol groups in gemini cationic surfactants with C12H25 chain affects the sizes of micelles at concentrations greater than CMC. It was discovered that the obtained gemini cationic surfactants have a biocidal character.  相似文献   

5.
以三氟乙酸乙酯和N,N-二甲基乙二胺为原料,经酰化反应制得中间体NDAET;然后将NDAET与溴代十二烷发生季铵化反应得到氟化季铵盐表面活性剂N,N-二甲基-N-{2-[(2,2,2-三氟乙酰基)氨基]乙基}-1-十二烷基铵溴化物(NDAET-12)。通过FTIR、13CNMR、1HNMR对其结构进行了表征。考察了反应物物质的量比、反应时间、反应温度、溶剂用量对NDAET-12产率的影响。在单因素实验的基础上,采用正交实验对NDAET-12的合成工艺进行了优化。NDAET-12的最佳合成工艺条件为:n(NDAET)∶n(溴代十二烷)=1.0∶1.3,NDAET质量为2.76g,反应时间12h,反应温度90℃,溶剂用量为20mL。在该条件下进行平行验证实验,得到NDAET-12的平均产率为86.75%。热重分析表明,NDAET-12是一种热稳定性较好的表面活性剂。对NDAET-12的临界胶束浓度(CMC)、表面活性和乳化性能进行了测定。NDAET-12的CMC为0.8 g/L,γCMC=25.15 mN/m,表面活性较好。与十二烷基三甲基溴化铵(DTAB)和十六烷基三甲基溴化铵(CTMAB)相比,NDAET-12从乳化体系中分出10mL所需要的时间最长,为473s,具有优异的乳化性能。  相似文献   

6.
彭玉洁  崔元臣 《化工时刊》2006,20(10):27-29
以棉籽油为基本原料合成了一种季铵型阳离子表面活性剂,并对其表面张力和临界胶束浓度进行了测定。结果表明;该种阳离子表面活性剂具有较好的表面活性。  相似文献   

7.
Synthesis of cationic polysaccharide (Aloe) Schiff base surfactants was described and their chemical structures were confirmed by using FTIR spectroscopic, H‐NMR and UV analysis. The surface activities of these surfactants were measured, including surface tension, critical micelle concentration, effectiveness, efficiency, maximum surface excess and minimum surface area at 25 °C, interfacial tension and emulsification power at 25 °C. Adsorption and micellization free energies of these amphiphiles in their solutions showed a good tendency towards adsorption at the interfaces.  相似文献   

8.
Ester-quat surfactants in the series of (dodecanoyl oxy) propyl n-alkyl dimethyl ammonium bromide referred to here as LC3Cm (where m is the hydrocarbon chain lengths 8, 12 and 14) were synthesized and characterized by the usual spectroscopic methods (NMR, IR, MS…). Their physico-chemical properties were investigated by surface tension and conductimetric measurements. From surface tension measurements, isotherms and thermodynamic adsorption parameters were determined. The critical micelle concentration (CMC), the degree of counter ion dissociation (α) of micelles in the water and the standard Gibbs free energy $( \Updelta G_{\text{m}}^{0}) $ , of micellization were also determined by conductimetric measurements. The results obtained from both methods were compared to the similar surfactants in the series of quaternary ammonium surfactants. Optical microscopy was also used to study the behavior of anhydrous surfactants and the binary water/surfactant system as a function of temperature.  相似文献   

9.
糖基季铵盐表面活性剂的合成与表征   总被引:7,自引:0,他引:7  
刘振东  梁鹏龙  陈小斌  余甲贤 《精细化工》2007,24(9):870-875,880
用葡萄糖、乳糖与十二胺的反应及随后的烷基化反应,合成了两种含季铵阳离子基团的糖基表面活性剂,通过电喷雾质谱(ESI-MS)对所得产品及关键中间体进行了结构表征。糖胺化反应的最佳溶剂为甲醇、乙醇(对葡萄糖)和水-异丙醇(对乳糖),反应温度不高于55℃,n(糖)∶n(胺)=1∶(1.2~1.6)。葡萄糖的胺化和烷基化反应提纯后的收率分别为79.1%和63.7%。乳糖的胺化和烷基化反应提纯后的收率分别为83.2%和60.1%。两种季铵盐表面活性剂的CMC分别为10.0 mmol/L和5.9 mmol/L,γCMC分别为33.2 mN/m和29.8mN/m。两种季铵盐质量浓度为5 g/L水溶液的初始起泡高度分别为8.5 cm和9.5 cm,30 min后为3.9 cm和4.4 cm。10 g/L的乳糖季铵盐水溶液的帆布沉降时间为1.2 s。两种季铵盐用于涤纶织物的抗静电整理,葡糖季铵盐在质量浓度为10 g/L、乳糖季铵盐在质量浓度为5 g/L时,就可以使摩擦静电压的半衰期下降到4 s。  相似文献   

10.
The novel anionic surfactant sodium 3‐oxo‐2‐(3‐(4‐sulphonatophenyl)triaz‐2‐enyl)octadecanoate (SSTO) was prepared from renewable raw materials; glycine and palmitic acid. Surface and bulk properties of SSTO were investigated by surface tension and electrical conductivity techniques at 298, 308, 318 and 328 K. Surface properties including critical micelle concentration (CMC), maximum surface excess concentration (Γmax), minimum area per molecule (Amin), surface tension at CMC (γCMC), effectiveness of surface tension reduction (ΠCMC), efficiency of surface adsorption (pC20), and degree of counterion dissociation (α) were determined. The thermodynamic parameters of micellization (Δmic, Δmic and Δmic) and adsorption (Δad, Δad and Δad) were also investigated at 298, 308, 318 and 328 K. The effect of 3 wt% n‐propanol, n‐butanol and n‐pentanol on surface tension and conductivity at 298 K was also determined.  相似文献   

11.
含氟铵盐和季铵盐型阳离子表面活性剂的合成   总被引:2,自引:0,他引:2  
以六氟丙烯三聚体和N,N-二甲基丙二胺为原料,合成了2-三氟甲基-3-七氟异丙基-2-全氟戊烯-4- (N,N-二甲胺丙基)亚胺(I),然后将其分别与盐酸和溴乙烷反应,制得含氟铵盐(Ⅱ)和季铵盐(Ⅲ)阳离子表面活性剂,通过红外光谱和核磁共振对分子结构进行了表征,其临界胶束浓度(CMC)为9.2×10-3mol/L,最低表面张力 19.0mN/m;(?)可适合任何条件,其CMC为8.05×10-3mol/L,最低表面张力为22.0mN/m。  相似文献   

12.
Two generations of novel linear-dendritic carboxylate surfactants C18-G1-(COONa)2 and C18-G2-(COONa)4 have been synthesized by the divergent method and their structures are characterized by 1H Nuclear Magnetic Resonance and Infrared analysis. The electrical conductivity measurement is used to measure the Krafft temperatures of C18-G1-(COONa)2 and C18-G2-(COONa)4, which are much smaller than those of the corresponding conventional surfactant sodium stearate. The markedly enhanced solubility of two linear-dendritic surfactants is ascribed to the high hydrophilicity of surfactant headgroups induced by the carboxylate and ester groups. The critical micelle concentration (CMC) values obtained from both the electrical conductivity and surface tension measurements indicate that the micellizations of linear-dendritic surfactants become favorable with the increase in the number of the surfactant headgroup. However, the surface activity parameters including the surface tension at the CMC, maximum surface excess, and minimum surface area reveal that C18-G1-(COONa)2 exhibits greater efficiency in absorbing at the air/water interface compared to C18-G2-(COONa)4, owing to their different steric repulsions of the surfactant headgroups. In addition, C18-G1-(COONa)2 and C18-G2-(COONa)4 have higher emulsifying ability than the conventional surfactants sodium stearate and sodium octadecyl sulfate.  相似文献   

13.
咪唑啉基季铵盐型双子表面活性剂的合成与性能   总被引:1,自引:1,他引:1  
葛君 《精细化工》2011,28(5):447-450
以环氧氯丙烷为连接剂,油酸、二乙烯三胺分别为疏水和亲水基团的初始原料合成了一种咪唑啉基季铵盐型双子表面活性剂,通过IR1、HNMR确证了目标产物结构。研究了其在水溶液中对苯的乳化力、稳泡能力、亲水亲油平衡值、表面张力的影响。动态激光散射法测试了双子咪唑啉基季铵盐乳化制备O/W型乳状液的乳胶粒径尺寸,利用双子表面活性剂作为乳化剂,油酸为分散相。静态失重法评价了双子表面活性剂作为缓蚀剂对Q235钢在质量分数8%溶液中的缓蚀性能。结果表明,所合成的双子咪唑啉基季铵盐具有较好的表面活性,临界胶束浓度CMC约为2×10-4mol/L,γCMC为31.40 mN/m,HLB值为14.2,对苯的乳化能力及稳泡性能良好。该乳液稳定,在25~50℃时,O/W乳液的胶粒尺寸在216~236 nm,是一种性能良好的O/W型乳化剂。失重法测定结果表明,该双子咪唑啉基季铵盐型表面活性剂缓蚀性能优于相应单链咪唑啉季铵盐表面活性剂。  相似文献   

14.
该文以2-氯乙胺盐酸盐和十八烷基叔胺为原料,合成了一种胺基型阳离子表面活性剂——N-十八烷基-N,N'-二甲基-乙基-1,2-胺。通过IR和1HNMR对其结构进行了确证;并得到优化的合成条件为:物料比nb/na为1.20,反应温度为70℃,反应时间为7 h,p H=7。采用电导法测定不同p H下该表面活性剂的临界胶束浓度(CMC),发现CMC随着p H的降低而减小。该表面活性剂在Na Sal溶液质量分数为1%时,能形成蠕虫状胶束。流变性能测试表明,体系具有蠕虫状胶束的剪切稀释性特征和凝胶特性,同时具有p H响应,能在酸性条件下增黏,是一种智能型蠕虫状胶束体系。  相似文献   

15.
以N,N-二甲基十二烷基叔胺与2,2′-二氯乙醚为原料,合成了季铵盐型gemini表面活性剂QAGS;采用IR和元素分析对合成产物进行了结构表征;研究了反应时间、溶剂类型及用量以及反应物物质的量比对产率的影响;并考察了QAGS的表面活性。结果表明:当N,N-二甲基十二烷基叔胺和2,2′-二氯乙醚的物质的量比为3.0∶1、反应介质为乙腈、乙腈用量为45mL、反应时间为72h时,QAGS的产率最高达22.76%;QAGS水溶液的表面张力随其浓度的增大而急剧减小,浓度达到1.054mmol·L-1时,表面张力基本不变;QAGS的饱和吸附量为1.597×10-6 mol·m-2,分子截面积为1.04nm2。  相似文献   

16.
Two series of quaternary cationic surfactant were synthesized by reaction of 8-hydroxyquinoline and 2-hydroxypyridine with long chain alkyl halides (dodecyl, tetradecyl- and hexadecyl-bromide). Surface tension was measured in aqueous solution for different concentrations at 25 °C. Various surface properties of the synthesized surfactants were evaluated, particularly critical micelle concentration (CMC), efficiency (ΠCMC) as well as maximum surface excess (Γmax) and minimum surface area (A min). Micellization and adsorption in liquid/air interfaces thermodynamics were investigated. The synthesized cationic surfactants were evaluated for their biocidal activity. All compounds prepared showed good antibacterial and antifungal activities.
Dina A. IsmailEmail:
  相似文献   

17.
超支化吉米奇(Gemini)季铵盐的合成、性能与应用   总被引:1,自引:0,他引:1  
以十二叔胺、环氧氯丙烷为原料,在80℃反应4h先合成季铵盐,然后再在催化条件下,85℃反应8h聚合成超支化Gem in i季铵盐。研究了超支化Gem in i季铵盐的特殊性能,并讨论了其在油田、造纸、工业水处理、印刷电路板、农药、纺织印染助剂等领域中的应用。  相似文献   

18.
Trimeric betaine surfactants tri[(N‐alkyl‐N‐ethyl‐N‐sodium carboxymethyl)‐2‐ammonium bromide ethylene] amines were prepared with raw materials containing tris(2‐aminoethyl) amine, alkyloyl chloride, lithium aluminium hydride, sodium chloroacetate, and bromoethane by alkylation, Hoffman degradation reaction, carboxymethylation and quaternary amination reaction. The chemical structures of the prepared compounds were confirmed by FTIR, 1H NMR, MS and elemental analysis. With the increasing length of the carbon chain, the values of their critical micelle concentration initially decreased. Surface active properties of these compounds were superior to general carboxylate surfactants C10H21CHN+(CH3)2COONa. The minimum cross‐sectional area per surfactant molecule (Amin), standard Gibbs free energy adsorption (ΔGads) and standard Gibbs free energy micellization (ΔGmic) are notably influenced by the chain length n, and the trimeric betaine surfactants have greater ability to adsorb at the air/water interface than form micelles in solution. The efficiency of adsorption at the water/air interface (pC20) of these surfactants increased with the increasing length of the alkyl chain. Their foaming properties, wetting ability of a felt chip, and lime‐soap dispersing ability were also investigated.  相似文献   

19.
氧乙烯联接链的季铵盐Gemini表面活性剂合成及胶团化特性   总被引:6,自引:0,他引:6  
游毅  赵剑曦  姜蓉  黄长沧 《精细化工》2004,21(8):571-574,585
合成了含氧乙烯联接链的季铵盐Gemini表面活性剂C12 2 En C12·2Br〔C12=C12H25N+(CH3)2,2=CH2CH2,En=(OC2H4)n,2Br=2Br-,n=1,2,3〕。以电导和稳态荧光法研究了胶团化行为,结果表明,C12 2 En C12·2Br的胶团化能力比其单体表面活性剂十二烷基三甲基溴化铵(C12TABr)高得多,接近于以2个亚甲基构成联接链的C12 2 C12·2Br。胶团聚集数N和表面反离子结合度K0也与C12 2 C12·2Br胶团相当。C12 2 En C12·2Br胶团化过程呈现焓/熵补偿现象,以n=1的胶团最为稳定。  相似文献   

20.
The aggregation morphology of 2 cationic surfactants (cetyldimethylethanolammonium bromide and cetyldiethylethanolammonium bromide), an anionic surfactant (sodium dodecylbenzenesulfonate), a nonionic surfactant (Triton X‐100), and 2 gemini surfactants (16‐4‐16,2Br?[butanediyi‐1,4‐bis(dimethyldohexylammonium bromide)] and 16‐6‐16,2Br?[hexanediyi‐1,6‐bis(dimethyldohexylammonium bromide)]) in the presence of the ionic liquid (IL) 1‐ethyl‐3‐methylimidazoliumbromide [Emim][Br] is studied using various techniques such as surface tension, conductivity, and UV–visible and fluorescence spectroscopy. Increasing the concentration of [Emim][Br] results in a decrease in the critical micelle concentration (CMC) value of the surfactants. Various interfacial properties, namely the surface excess concentration (Гmax), minimum area per molecule at the air–water interface (Amin), and surface pressure at the CMC (πcmc), as well as the thermodynamic parameters such as free energy of the given air/water interface (), Gibbs free energy of micelle formation (), Gibbs free energy of micellization per alkyl tail (), Gibbs energy of transfer (), and standard free energy of adsorption () were also investigated. The aggregation number (Nagg) was determined by the fluorescence method. It was observed that Nagg decreased with increasing weight‐percent of the IL.  相似文献   

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