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Minggui Chen Lijuan Luo Xingqi Hu Jitao Yang 《Journal of surfactants and detergents》2013,16(3):327-332
A series of carboxylate gemini surfactants, which contain two hydrocarbon chains linked by amide groups, two carboxylate groups, a flexible alkane spacer were synthesized by three-step reactions and named alkylidene–bis-(N,N′-dodecyl-carboxypropylamides) (2C12H25CnAm; n = 2, 3, 4, 6, 8 is the number of methylene groups of the spacer), their structures were confirmed by FTIR,1H NMR, and LC–MS/TOF, and their purity checked by HPLC. The micellar properties with increasing spacer chain length of these gemini surfactants were determined by surface tension methods. The critical micelle concentration (CMC) varies slightly with spacer chain length; surface tension at CMC(γCMC), the tendency of micellization versus adsorption, CMC/C20, the minimum area per surfactant molecule at the air/solution interface (ACMC), all decrease with increasing spacer chain length; surface reduction efficiency, pC20, the surface excess at the air/solution interface (ГCMC) increase with increasing spacer chain length. The results probably indicate that increasing spacer chain length of these carboxylate gemini surfactants will increase spacer incorporation into the double hydrophobic chain. 相似文献
3.
Ravan A. Rahimov Gulnara A. Ahmadova Seyid-Zeynab F. Hashimzade Elmar Imanov Hajibala G. Khasiyev Nazani K. Karimova Fedor I. Zubkov 《Journal of surfactants and detergents》2021,24(3):433-444
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
4.
A series of anionic gemini surfactants with the same structure except the spacer nature have been studied. Their solution
properties were characterized by the equilibrium surface tension and intrinsic fluorescence quenching method. The critical
micelle concentrations (CMC), surface tension at cmc, C20, and the micelle aggregation number (N) were obtained. The surface tension measurements indicate that these gemini surfactants have much lower cmc values and great
efficiency in lowering the surface tension of water compared with those of conventional monomeric surfactants. Furthermore,
the standard free energy of micellization for anionic gemini surfactants was also determined. The results showed that the
nature of the spacer has an important effect on the aggregation properties of gemini surfactants in aqueous solutions. The
surfactant with a hydrophilic, flexible spacer was more readily able to form micelle compared with the surfactant with a hydrophobic,
rigid spacer, which leads to a lower CMC value, larger N, more negative free energy of micellization, and a more closely packed micelle structure. 相似文献
5.
Micellization of four cationic quaternary ammonium gemini surfactants, having a diethyl ether or hexyl spacer with the alkyl chain lengths of 12 and 16 carbon atoms, was studied using isothermal titration microcalorimetry (ITC) and electrical conductivity measurements in the temperature range from 298.15 to 313.15 K. In this temperature range, where surfactants are normally applied, the temperature almost does not influence the critical micelle concentration (CMC) and the degree of micelle ionization (α) values of the gemini surfactants, and the replacement of a hexyl spacer by a diethyl ether spacer leads to a slight decrease in the CMC and α values. However, as the alkyl chain length increases from 12 to 16 carbon atoms, the CMC values significantly decrease from 0.99–1.19 mM to 0.020–0.057 mM. In particular, the enthalpy of micellization (ΔHmic ) and the associated thermodynamic parameters show obvious changes with varying temperature and molecular structure. ΔHmic becomes much more exothermic at higher temperature or for the surfactants with a more hydrophilic spacer. Moreover, the heat capacity change of micellization (ΔC P, mic ) is less exothermic for the surfactants with a more hydrophilic spacer or a longer alkyl chain. The enthalpy–entropy compensation data show that the surfactants with longer alkyl chains have a more stable micellar structure. 相似文献
6.
Synthesis and Evaluation of Novel Amido-Amine Cationic Gemini Surfactants Containing Flexible and Rigid Spacers 下载免费PDF全文
S. M. Shakil Hussain Muhammad Shahzad Kamal Bassam El Ali Abdullah S. Sultan 《Journal of surfactants and detergents》2017,20(4):777-788
New amido‐amine‐based cationic gemini surfactants with flexible and rigid spacers and different hydrophobic tails were synthesized and characterized. These gemini surfactants were prepared by a modified procedure through amidation of long chain carboxylic acids using 3‐(dimethylamino)‐1‐propylamine followed by treatment with halohydrocarbons. The effect of the trans and cis conformation of the spacer double bond was investigated by means of critical micelle concentration, surface tension reduction, and thermal stability. The short‐term thermal stability of the gemini surfactants was assessed using thermogravimetric analysis (TGA) and the long‐term thermal stability was examined by a unique approach based on structure characterization techniques including NMR (1H and 13C) and FTIR analysis. TGA results demonstrated excellent short‐term thermal stability since no structure degradation was observed up to 200 °C. Structural characterization revealed impressive long‐term thermal stability of the gemini surfactants with no structure decomposition after exposing them to 90 °C for 10 days. The critical micelle concentration of gemini surfactants was found to be in the range of 0.77 × 10?4–3.61 × 10?4 mol L?1 and corresponding surface tension (γCMC) ranged from 30.34 to 38.12 mN m?1. The surfactant with the trans conformation of spacer double bond showed better surface properties compared to the surfactant with the cis conformation of spacer double bond. Similarly, increasing surfactant tail length and spacer length resulted in decreasing CMC values. Moreover, bromide counterion showed improved surface properties compared to chloride counterion. 相似文献
7.
Shengnan Guo Xiaowen Sun Qichao Zou Jinzhi Zhang Hong Ni 《Journal of surfactants and detergents》2014,17(6):1089-1097
A series of cationic gemini surfactants containing two dimethylalkylammonium chains linked by ethylene glycol bisacetyl spacers were synthesized [Gm‐AnA‐m, G = gemini surfactant, m = 12 (–C12H25), 14 (–C14H29), or 16 (–C16H33), A = acetyl, and n = 2, 3, or 4 is the number of ethylene glycol units in the spacers]. Because of the inductive effect of the oxygen atom in the spacer, acylation can take place using chloroacetyl chloride instead of bromoacetyl bromide which helps to limit the use of environmentally harmful reagents. Critical micelle concentrations were determined using conductivity measurements. The antibacterial activities of the surfactants against Gram‐positive bacterium Staphylococcus aureus and Gram‐negative bacterium Escherichia coli were evaluated from the minimum inhibitory concentration (MIC), minimum bacterial concentration, a time–kill study, and the inhibitory zone. Increasing the length of the spacer did not result in an obvious change of antibacterial activity. However, increasing the length of the alkyl chain apparently increased the antibacterial activity against S. aureus but decreased the antibacterial activity against E. coli. The G12‐A2A‐12 surfactant had the lowest CMC of 1.26 mmol L?1 and exhibited the best antibacterial activity with a MIC of 32 μg mL?1 toward S. aureus and 64 μg mL?1 toward E. coli in the presence of 105 CFU of bacteria. This work indicated that these cationic gemini surfactants have potential applications as antibacterial agents and emulsifiers. 相似文献
8.
Constructing Gemini‐Like Surfactants with Single‐Chain Surfactant and Dicarboxylic Acid Sodium Salts 下载免费PDF全文
Construction of gemini‐like surfactants using the cationic single‐chain surfactant cetyltrimethylammonium bromide C16H33N(CH3)3Br2 (CTAB) and the anionic dicarboxylic acid sodium salt NaOOC(CH2)n‐2COONa (CnNa2, n = 4, 6, 8, 10, 12) by way of non‐covalent interactions has been investigated by surface tension measurements, hydrogen‐1 nuclear magnetic resonance (1H NMR) spectroscopy and isothermal titration microcalorimetry (ITC). The critical micelle concentrations (cmc) of the CTAB/CnNa2 mixtures are obviously lower than that of CTAB and strongly depend on the mixing ratio. Moreover, the cmc values of the CTAB/CnNa2 mixtures decrease gradually with an increasing methylene chain length of CnNa2, indicating hydrophobic interaction between the hydrocarbon chains of CTAB and CnNa2 facilitates micellization of the mixtures. In particular, the ITC curves and 1H NMR spectra indicate that the binding ratio of CTAB to CnNa2, except C4Na2, is around 2:1, i.e., (CTAB)2CnNa2. Additionally, CTAB/CnNa2 mixtures are soluble in a whole molar ratio and concentration ranges have been studied, even at the electrical neutralization point. Therefore, these results reveal that highly soluble gemini‐like surfactants are conveniently constructed with oppositely‐charged cationic single‐chain surfactants and dicarboxylic acid sodiums. In an attempt at improving the performance of surfactants this work provides guidance for choosing additives that form gemini‐like surfactants via an uncomplicated synthesis. 相似文献
9.
Synthesis and Surface Active Properties of tri[(N‐alkyl‐N‐ethyl‐N‐Sodium carboxymethyl)‐2‐Ammonium bromide ethylene] Amines 下载免费PDF全文
Ming Zhou Gang Luo Xingwen Wang Ze Zhang Gang Wang 《Journal of surfactants and detergents》2015,18(5):837-844
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
10.
A series of novel cationic gemini surfactants [CnH2n+1–O–CH2–CH(OH)–CH2–N+(CH3)2–(CH2)2]2·2Br? [ 3a (n = 12), 3b (n = 14) and 3c (n = 16)] having a 2‐hydroxy‐1,3‐oxypropylene group [?CH2–CH(OH)–CH2–O–] in the hydrophobic chain have been synthesized and characterized. Their water solubility, surface activity, foaming properties, and antibacterial activity have been examined. The critical micelle concentration (CMC) values of the novel cationic gemini surfactants are one to two orders of magnitude smaller than those of the corresponding monomeric surfactants. Furthermore, the novel cationic gemini surfactants have better water solubility and surface activity than the comparable [CnH2n+1–N+(CH3)2–(CH2)2]2·2Br? (n‐4‐n) geminis. The novel cationic gemini surfactants 3a and 3b also exhibit good foaming properties and show good antibacterial and antifungal activities. 相似文献
11.
N-Alkyl glucamines can be reacted with α,ω-diepoxides to yield gemini (dimeric) surfactants similarly to the reaction of glucamine
with terminal epoxides. Under the conditions chosen for this work, epoxides were quantitatively converted in the presence
of an equimolar amount of amine to gemini surfactants. Reactions could be carried out under mild conditions (70°C) in methanol,
and products were obtained quantitatively by removing the solvent. The combination of N-octyl glucamine, N-decyl glucamine, or N-dodecyl glucamine with diepoxides of α,ω-diolefins having chain lengths of C8, C9, C10, or C14 resulted in gemini surfactants differing in spacer length and length of hydrophobic alkyl chains. Surface-active properties
were studied by measuring surface tension and evaluating foaming properties. Tensiometric studies showed the reduction of
surface tension down to 29–33 mN/m and critical micelle concentrations often in the range of 3–150 mg/L. Comparison of a selected
gemini surfactant [1,8-bis(N-dodecyl glucamino-2,7-octane diol] with its corresponding “single surfactant” demonstrated the enhancement of surface-active
properties afforded by the gemini structure. 相似文献
12.
Gemini Surfactants Foam Formation Ability and Foam Stability Depends on Spacer Length 总被引:1,自引:0,他引:1
A series of cationic gemini surfactants containing different spacer length were synthesized and analyzed structurally. It was shown that the surface tension (σ) and critical micelle concentration (CMC), which had a maximum for the n-C4H8 spacer depended on the spacer length. The foaming ability and foam stability are high for the gemini surfactants with short spacers (C2H4 to n-C4H8), while longer spacers lead to a distinct decrease of these foam parameters. Foaming properties are discussed in terms of configuration and conformation of a surfactant molecule and in relation to micellization state kinetic. 相似文献
13.
A series of dialkyl diphosphate gemini surfactants has been synthesized using C18 as hydrophobic chains and phosphate as head groups. Three flexible spacers have been used. In the present study, an attempt has also been made to synthesize mono octadecyl phosphate (MOP) at 35°C, which was used as an intermediate in the synthesis of geminis. This long chain of MOP has been effectively converted to gemini surfactants and subsequently converted to their disodium salts. The effect of reaction variables like temperature, duration, molar ratios of reactants, catalyst and spacer on the yield of dialkyl diphosphate gemini surfactant has also been reported. The MOP, gemini surfactants and disodium salt of gemini surfactants were characterized using FT‐IR and 1H‐NMR. Surface active and physico‐chemical properties of synthesized gemini surfactants and their monomer were also determined. The results revealed that the yield of dialkyl diphosphate gemini surfactants ranged from 80 to 90%. Among all synthesized dialkyl diphosphate gemini surfactants D, S‐1,6‐GSOD had maximum anionic content, i.e. 80.7%, showed highest foaming ability and superior dispersing ability, whereas D, S‐1,8‐GSOD showed low cmc values, i.e. 0.00012 mM/L; minimum surface tension and interfacial tension, i.e. 39.1 and 36.3 mN/m, respectively. 相似文献
14.
A series of novel dissymmetric gemini surfactants, [C m H2m+1COOC2H4(CH3)2N(CH2)3N(CH3)2C2H4OOCC n H2n+1]Br2 was synthesized and symbolized as m-s–n. The Krafft temperatures and surface tension curves of the dissymmetric gemini surfactants were measured using an electrical conductivity method and a drop volume method. The low Krafft temperatures indicate very good solubility of these esterquat gemini surfactants. With the increasing numbers of carbon atoms in the hydrophobic alkyl chain, the critical micelle concentration (CMC) and the minimum surface area (A min) decrease, and the efficiency of surface tension reduction (pc20) increases. With the same numbers of carbon atoms in the hydrophobic alkyl chain, the dissymmetric gemini surfactant has a lower CMC and a smaller A min than the corresponding symmetric gemini surfactant due to the enhanced hydrophobic interactions. 相似文献
15.
Antimicrobial and Cytotoxic Properties of Bisquaternary Ammonium Bromides of Different Spacer Length 下载免费PDF全文
Katarzyna Łudzik Kinga Kustrzepa Magdalena Kowalewicz‐Kulbat Renata Kontek Bogdan Kontek Aneta Wróblewska Małgorzata Jóźwiak Daria Lulo 《Journal of surfactants and detergents》2018,21(1):91-99
A group of cationic gemini surfactants (bisquaternary ammonium bromides) with different spacer chain lengths (8–6–8, 8–7–8, 8–8–8, 8–9–8) was investigated, paying special attention to antimicrobial and the cytotoxic properties as well as their antimicrobial activity during long‐term storage. It was shown that the compounds investigated exhibit excellent antimicrobial activity against Gram‐positive bacteria (Staphylococcus aureus) and Gram‐negative bacteria (Pseudomonas aeruginosa) as well as antifungal properties (Candida albicans). The gemini surfactants tested had the differential level of cytotoxicity against normal lymphocytes. It was shown that the spacer chain length plays an important role in antibacterial activity and influences the cytotoxicity. The gemini surfactants with shorter spacer chain length, that had higher critical micelle concentration, showed generally weaker antibacterial properties, but on the other hand, these exhibited lower level of cytotoxicity. Furthermore, the aqueous solution of gemini surfactants exhibited the same antimicrobial activity even after 3 months. 相似文献
16.
A series of alkylbetaine zwitterionic gemini surfactants, 1,2-bis[N-methyl-N-carboxymethyl-alkyl-ammonium]ethane (C
n
Ab, n = 8, 10, 12, or 14), were synthesized by alkylation of N,N′-dimethylethylenediamine with an alkyl bromide, followed by reaction with sodium 2-bromoacetate. Their solution properties
were characterized by surface tension, steady-state fluorescence, and rheological measurements. Surface-tension measurements
showed C
n
Ab had lower critical micelle concentration (CMC) and higher efficiency in lowering the surface tension than their corresponding
monomeric surfactants. The logCMC of C
n
Ab decreased linearly with increasing chain lengths up to 12. Viscosity measurements showed only C10Ab could enhance aqueous solution viscosity at high concentrations. 相似文献
17.
R. G. Bistline Jr. W. R. Noble W. M. Linfield 《Journal of the American Oil Chemists' Society》1976,53(2):64-68
Surface active amphoteric derivatives were prepared from alkylbenzenesulfonyl chlorides. Industrial detergent alkylates, as
well as benzene and pure 1-phenylalkanes whose side chains ranged from C1 to C12, were used as starting materials in this study of chemical structure-physical property relationships. The alkylbenzenes were
first converted into the corresponding alkylbenzenesulfonyl chlorides with chlorosulfonic acid, and the sulfonyl chlorides
were further treated with N,N-dimethyl-1,3-diaminopropane or N,N-bis-(2-hydroxyethyl)-1,3-diaminopropane. The reaction products
were quaternized with propanesultone to produce amphoteric surfactants in high yields. The N,N-dimethyl herivatives of pure
phenylalkanes were white crystalline powders, whereas the N,N-bis-(2-hydroxyethyl) derivatives were light , lime soap dispersing
requirement, surface tension, wetting ability, and calcium ion stability were determined. The commercial detergent alkylate
derivatives showed good detergency by themselves as well as in formulations with soap or with soap and silicate builder. Good
lime soap dispersing properties were observed with compounds possessing a side chain of at least 4 carbon atoms.
Presented at the AOCS Fall Meeting, Philadelphia, September 1974. 相似文献
18.
Yangchun Xie Jie Li Ruihua Zhu Tong Sun Guangmiao Qu 《Journal of surfactants and detergents》2019,22(3):421-430
Three novel carboxylate gemini surfactants (3CntaDA, n = 8, 10, and 12) were synthesized by two simple steps, and their structures were characterized using FT-IR and 1H NMR. The surface activities of these surfactants were obtained from surface tension measurements at different temperatures, and the surface parameters containing the critical micelle concentration (CMC), surface tension (γ), minimum surface area per molecule ( Amin ), and maximum surface excess concentration ( Γmax ) were obtained from surface tension measurements. The experimental results show that 3CntaDA surfactants have higher surface activities compared with the corresponding conventional surfactants. The thermodynamic parameters of the micellization process were investigated, and the calculated results show that it was an exothermic and spontaneous process. The emulsification and foam performance of these surfactants were also evaluated at different concentrations at 298.15 K. 相似文献
19.
Preparation,Characterization and Properties of Novel Cationic Gemini Surfactants with Rigid Amido Spacer Groups 下载免费PDF全文
Dongqing Xu Banghua Qi Di Fang Xuemei Zhang Ting Zhang 《Journal of surfactants and detergents》2016,19(1):91-99
A series of novel cationic gemini surfactants with rigid amido groups inserted as the spacers, named C 12 ‐PPDA‐C 12 , C 14 ‐PPDA‐C 14 and C 16 ‐PPDA‐C 16 , were synthesized by a two‐step reaction with dimethyl terephthalate, N,N‐dimethyl propylene diamine and alkyl bromide as raw materials. The chemical structures of the prepared compounds were confirmed by IR, 1H and 13C NMR and element analysis. Surface activity properties of the synthesized compounds were investigated by surface tension, electrical conductivity and fluorescence. Increasing the number of carbon atoms in the hydrophobic alkyl chain, decreased the critical micelle concentration (CMC), surface tension at the CMC and the minimum surface area. Other relevant properties including foaming ability and emulsion stability were investigated. The results indicated that the synthesized gemini surfactants possess good surface properties, emulsifying properties and steady foam properties. 相似文献
20.
Surface and Aggregation Properties of Synthesized Cetyl Alcohol Based Bis-Sulfosuccinate Gemini Surfactants in Aqueous Solution 下载免费PDF全文
A series of cetyl alcohol based anionic bis‐sulfosuccinate gemini surfactants (BSGSCA1,4; BSGSCA1,6 and BSGSCA1,8) with different spacer lengths was prepared using dibromoalkanes. The surfactant structure was elucidated using elemental analysis, Fourier transform infrared spectroscopy (FT‐IR) and nuclear magnetic resonance spectroscopy (NMR). Surface tension measurements were used to determine the critical micelle concentration (CMC), the surface tension at the CMC (γCMC), surface pressure at the CMC (πCMC) and efficiency of adsorption (pC20). On the basis of surface studies, the CMC and γCMC decreases with increasing length of the spacer group. The micelle aggregation number, determined by fluorescence quenching studies, increases with increasing surfactant concentration above the CMC. The micropolarity in the micelle increases with increasing length of the spacer and decreases with increasing surfactant concentration. 相似文献