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1.
Xin Li Zhiyong Hu Hailin Zhu Sufen Zhao Duanlin Cao 《Journal of surfactants and detergents》2010,13(3):353-359
A series of novel dialkyl disulfonate gemini surfactants (2Cn-SCT where n is the carbon number of the hydrophobic chain) were synthesized from cyanuric chloride, aliphatic amine and taurine.
The chemical structures of the prepared compounds were confirmed by 1H NMR, 13C NMR, IR spectra, and ESI–MS. Their critical micelle concentrations (CMC) in the aqueous solutions at 25 °C were determined
by surface tension and electrical conductivity methods. With the increasing length of the carbon chain, the values of their
CMC initially decreased, and then increased with an alkyl chain length of 14. The surface tension measurements of 2Cn-SCT (except for n = 14) determined that there is a low CMC, a great efficiency in lowering the surface tension, and a strong
adsorption at the air–water interface. In addition, adsorption and micellization behavior of 2Cn-SCT were estimated from pC
20, the minimum average area per surfactant molecule (A
min), and standard free energy micellization and adsorption (
\Updelta G\textmic° \textand \Updelta G\textads° \Updelta G_{\text{mic}}^{^\circ } \,{\text{and}}\,\Updelta G_{\text{ads}}^{^\circ } ). These properties are significantly influenced by the chain length n, and the adsorption is promoted more than the micellization. 相似文献
2.
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
3.
A cationic Gemini surfactant with a benzene ring (abbreviated as C14‐CGB) was synthesized in 2 steps with aniline, epichlorohydrin, and N,N‐dimethyltetradecylamine as starting materials. This product was characterized using mass spectroscopy and nuclear magnetic resonance (1H NMR). The critical micelle concentration (CMC) and surface tension (γcmc) of C14‐CGB were measured from 298 to 313 K and thermodynamic parameters of micellization were calculated. The results showed that the CMC and γcmc were 1.269 × 10?3 mol L?1 and 38.33 mN m?1 at 298 K, respectively. Moreover, upon increasing the temperature, the CMC increases, γcmc decreases, the maximum surface adsorption capacity (Γmax) decreases, and the minimum molecular area (Amin) increases. The emulsified asphalt test showed that C14‐CGB is a slow‐breaking asphalt emulsifier exhibiting excellent emulsifying ability. 相似文献
4.
Tomokazu Yoshimura Yoshifumi Koide Hideto Shosenji Kunio Esumi 《Journal of surfactants and detergents》2002,5(3):257-262
Maleic acid alkyl ester and N-alkyl maleamic acid monomers (RnMa and RnMaAm; n is alkyl chain length; n=6, 8, 10, 12, 14) were synthesized by the reaction of maleic anhydride with alkyl alcohol or alkylamine.
The telomerization of RnMa or RnMaAm in the presence of alkanethiol as a chain transfer agent gave telomer-type anionic surfactants (xRnMa, xRnMaAm; x is total average number of alkyl chains; x=2.8–3.3) having multialkyl chains and multicarboxylate groups. Their surface-active
properties were investigated by several techniques such as surface tension, foaming property, and emulsification power measurements.
Critical micelle concentrations (CMC) of xRnMa were 1/110–1/14 of those of RnMa with the same alkyl chain length. xRnMa and xRnMaAm gave higher efficiencies in lowering the surface tension than RnMa and RnMaAm in aqueous solutions. In particular, the surface tension of 3.2R12MaAm was 24.4 mN m−1 at the CMC. Foaming abilities and foam stabilities of xRnMa and xRnMaAm were higher than those of RnMa and RnMaAm. The addition of 300 ppm of Ca2+ to the aqueous solutions rendered the telomers less surface active. Shaking the aqueous solutions of telomers with toluene
emulsified them. The highly stable oil-in-water type emulsion was formed by using 3.0R10MaAm and 3.2R12MaAm, and the degree of emulsification was kept at a level of about 80% after 60 min of standing. Thus, telomer-type surfactants
showed excellent surface activities that were superior to the corresponding monomers as well as to conventional surfactants.
The relationship between alkyl chain length of the telomers and the properties of surface tension, foaming, and emulsification
was unclear. 相似文献
5.
Interfacial, thermodynamic, and morphological properties of decaoxyethylene n-dodecylether [CH3 (CH2)11(OCH2CH2)10OH](C12E10) in aqueous solution were analyzed by tensiometric, viscometric, proton nuclear magnetic resonance (NMR), and small-angle
neutron scattering (SANS) techniques. Dynamic and structural aspects at different temperatures in the absence and presence
of sugars at different concentrations were measured. Critical micelle concentrations (CMC) were determined by surface tension
measurements in the presence of ribose, glucose, and sucrose. The heat capacity (ΔC
p.m.), transfer enthalpy (ΔH
m.tr.), transfer heat capacities (ΔC
p.m.tr.), micellization constant (K
m
), Setchenow constant (K
S
N
), and partition coefficient (q) were determined and discussed as an extension of the usual thermodynamic quantities of micellization and adsorption at the
air-water interface. An enthalpy-entropy compensation effect was observed with an isostructural temperature (T
c
) of about 310 K for both micellization and interfacial adsorption. SANS measurements were taken to elucidate structural information,
viz., aggregation number (N
agg), shape, size, and number density (N
m
) on C12E10 micelles in D2O at different concentrations of sugars (0.05, 0.02, 0.3, and 0.5 M) and temperatures (30, 45, and 60°C). Intrinsic viscosity
gave the hydrated micellar volume (V
h
), volume of the hydrocarbon core (V
c
), and volume of the palisade layer of the oxyethylene (OE) unit (V
OE). SANS, as well as rheological data, supported the formation of nonspherical micelles with or without sugars. By SANS, we
also observed that at the studied temperature intervals, oblate ellipsoid micelles changed into prolate ellipsoids and the
number density of micelles decreased with an increase in temperature both in the presence and in the absence of sugars and
also on increasing the concentration of sugars. Proton NMR showed a change in chemical shift of the OE group of micelles above
the CMC. We also studied the phase separation of C12E10 by sugars in cloud point measurements. 相似文献
6.
Synthesis and study of the surface properties of long-chain alkylnaphthalene sulfonates 总被引:1,自引:0,他引:1
Long-chain alkylnaphthalene sulfonates were synthesized by means of a Wurtz-Fittig reaction, and the basic properties were
studied in water at 30°C. Through surface tension measurements, the following values were determined: the critical micelle
concentration (CMC) and the surface tension at the CMC (γCMC). The following values were calculated: area per molecule at the CMC (ACMC), standard free energy change of micellization (ΔG
mic
o
), standard free energy of adsorption (ΔG
ad
o
), and the “efficiency” of a surfactant in reducing surface tension (pC20). The micelle aggregation numbers were measured through steady-state fluorescence-quenching methods. As the chain length
of the hydrocarbon of n-alkylnaphthalene sulfonate increased, the Krafft temperature increased, the surface tension decreased, the value of CMC decreased,
pC20 increased, ΔG
ad
o
and ΔG
mic
o
became more negative, and the micelle aggregation number increased. The results showed that sodium α-(n-decyl)naphthalene sulfonate (DNS) had a high pC20, low Krafft temperature, and lower CMC than other surfactants in this study. Thus, DNS and the other n-alkylnaphthalene surfactants studied exhibit desirable properties that may be of value in some fields such as detergency,
oil recovery, and dyes. 相似文献
7.
Surface and aqueous properties of anionic gemini surfactants having dialkyl amide,carboxyl, and carboxylate groups 总被引:1,自引:0,他引:1
A systematic study of the equilibrium surface properties (in water and in the presence of 10−2 M NaCl) of a novel series of anionic gemini surfactants, (CH2)2[N(COCnH2n+1)CH(COOH)CH2COOH]·2NaOH (GA), where (n+1)=8, 10, 12, 14, and 16, was investigated. The responses of humans to closed patch tests with
(CH2)2[N(COC11H23)CH(COOH)−CH2COOH]2·2NaOH (GA-12) were also investigated. Premicellar self-aggregation (both in water and 10−2 M NaCl) occurred when the N-acyl group contained more than 14 carbon atoms, since the critical micelle concentration (CMC) values decreased and the pC20 values increased as (n+1) increased for (n+1) ≤14; the CMC values increased and the pC
20 values decreased as (n+1) increased for (n+1)>14, both in water and in 10−2 M NaCl. The absence of a break in the specific conductance-surfactant molar concentration plots for the GA homologs indicates
protonation of the carboxylate group and strong Na+ release during micellization. This is a structural characteristic of the anionic geminis having N-dialkylamide and carboxylate groups in a molecule. The skin irritation potential of GA-12 is lower than that of the corresponding
“monomer”, C11H23CON(CH3)CH(COOH)CH2(COOH)·NaOH, and the analog, C11H23CON(CH3)CH2COONa·H2O. 相似文献
8.
Tomokazu Yoshimura Yasuhiro Kiridoshi Yoshifumi Koide Hideto Shosenji Kunio Esumi 《Journal of surfactants and detergents》2002,5(2):159-164
N-(α-Carboxyalkyl)acrylamide telomer-type surfactants (xC
n−1
AmAc where n is alkyl chain length=6, 8, 10, 12; and x is degree of polymerization=3.3–13.1) were synthesized by the telomerization of monomer (C
n−1
AmAc) in the presence of the corresponding alkanethiol as a chain transfer agent and then investigated for their surface-active
properties. xC
n−1
AmAc telomers lowered the surface tension of aqueous solutions that were at pH 9–10. The critical micelle concentrations (CMC)
of the telomers were lower than those of the monomers with the same alkyl chain length, and the CMC values shifted to lower
concentrations with both increasing alkyl chain length and polymerization degree. xC9AmAc with x=3.3–6.3 gave the highest efficiencies in lowering the surface tension. The cross-sectional molecular areas per molecule of
xC
n−1
AmAc telomers were smaller than the values estimated on the assumption that they are assemblies of C
n−1
AmAc monomer units. The foaming abilities and the foam stabilities were both in the orders of xC7AmAc>xC9AmAc>xC5AmAc>xC11AmAc. Mixtures of aqueous solutions of xC
n−1
AmAc telomers and toluene formed oil-in-water emulsions. The emulsion-stabilizing abilities were in the orders of xC7AmAc>xC5AmAc>xC9AmAc=xC11AmAc. The addition of Ca2+ to the mixed solutions of telomers and toluene resulted in formation of water-in-oil type emulsions. Thus, the surface-active
properties of the telomers were influenced significantly by the alkyl chain length and the polymerization degree of the telomers.
In addition, these properties could be correlated with the hydrophilic-lipophilic balance (HLB); the highest surface activities
were observed by using xC
n−1
AmAc with HLB of 14–18. 相似文献
9.
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
10.
Xiaochen Liu Yongxiang Zhao Qiuxiao Li Tiliu Jiao Jinping Niu 《Journal of surfactants and detergents》2017,20(2):401-409
The equilibrium surface tension, dynamic surface tension, and interfacial tension (IFT) of fatty alcohol ether sulfonates (CmEnSO) were measured to investigate their adsorption behavior. The effect of NaCl and CaCl2 concentrations on the IFT was also studied. The results showed that the number of EO units has no significant effect on the critical micelle concentration (CMC) and CMC decreases with increasing the length of the hydrophobic group. The surface tension at the CMC increases with the increase of the number of EO units and the length of the hydrophobic group. At dilute surfactant concentration, the adsorption process for CmEnSO is controlled by diffusion; at higher concentration, it becomes a mixed diffusion‐kinetic adsorption mechanism. The IFT between CmEnSO solution and dodecane remains around 10?1 mN/m over a wide range of electrolyte concentrations (NaCl concentration from 25 to 210 g/L, CaCl2 concentration from 0.1 to 10 g/L). 相似文献
11.
Interfacial, thermodynamic, and performance properties of aqueous binary mixtures of α-sulfonato palmitic acid methyl ester,
C14H29CH(SO3Na)COOCH3(PES), and hexaoxyethylene monododecyl ether, CH3(CH2)11(OCH2CH2)6OH (C12E6), were investigated with tensiometric, conductometric, fluorimetric, and viscometric techniques. The critical micelle concentration
(CMC), maximum surface excess, minimum area per molecule of surfactant at the air/water interface, and the thermodynamics
of micellization and adsorption were determined. The CMC was very low for mixed systems, indicating probable use as a detergent
with less effect on the environment because of surfactant biodegradability and less amount in the environment. The interaction
parameter βm, computed by using the theory of Rubingh and Maeda, indicated an attractive interaction (synergism) between the surfactant
molecules, which was also confirmed by proton nuclear magnetic resonance studies in the mixed micelle. The micellar aggregation
number (N
agg), determined by using a steady-state fluorescence quenching method at a total surfactant concentration of about ∼10 mM at
25°C, was almost independent of the surfactant mixture composition. The micropolarity and the binding constant (K
sv) for the C12E6/PES mixed system were determined by the ratio of the intensities (I
1/I
3) of the pyrene fluorescence emission spectrum, and the local microenvironment inside the micelle was found to be polar. The
viscosity of the mixed system at all mole fractions suggested that mixed micelles are nonspherical in nature. The cloud point
of oxyethylene group-containing surfactants was increased by the addition of PES. Foaming was temperature dependent, and a
1∶1 mixed system showed minimum foaming. All performance properties were composition dependent. 相似文献
12.
Nabel A. Negm Ahmed F. El-Farargy Salah M. Tawfik Ahmad M. Abdelnour Hassan H. Hefni Manal M. Khowdiary 《Journal of surfactants and detergents》2013,16(3):333-342
Three series of nonionic surfactants derived from polytriethanolamine containing 8, 10, and 12 units of triethanolamine were synthesized. Structural assignment of the different compounds was made on the basis of FTIR and 1H‐NMR spectroscopic data. The surface parameters of these surfactants included critical micelle concentration (CMC), surface tension at the CMC (γCMC), surfactant concentration required to reduce the surface tension of the solvent by 20 mN m?1 (pC20), maximum surface excess (Γmax), and the interfacial area occupied by the surfactant molecules (Amin) using surface tension measurements. The micellization and adsorption free energies were calculated at 25 °C. 相似文献
13.
Synthesis of a new glycolipid and biosurfactant analog, methyl-12-[1′-β-d-lactosyl]-octadec-9-ene-1-oate (LOD), has been done from easily accessible renewable resources, namely, lactose and ricinoleic
acid from castor oil. Surface and thermodynamic properties at the air/water interface including critical micelle concentration
(CMC), aggregation number (<N>), maximal densities (Γmax), minimal area per molecule (A
min), surface pressure at the CMC (ΠCMC ) free energy of adsorption (ΔG
ad
0), and free energy of micelle formation per mole of monomer unit (ΔG
m
0) were investigated. The results indicate that this particular glycolipid, because of branching in the hydrophobic chain,
has a comparatively large A
min value and hence a very low CMC, aggregation number, and less free energy of micellization and adsorption at the air/water
inter-face than molecules with a straight hydrophobe, for example, n-dodecyl-β-d-maltoside. The effects of electrolytes (NaCl, KCl, CaCl2, and AlCl3) of the same ionic strength and of increasing ionic strength on the interfacial microenvironment of LOD were also investigated.
For the same anion, Cl−, and the same ionic strength, different cations were found to have different effects on the CMC of LOD. With increasing ionic
strength, different electrolytes were found to have different effects on the interfacially located, highly hydrated aqueous
layer of the LOD micelle. The water structure-making or-breaking ability of different cations from the interfacial microenvironment
of LOD was found to depend on the charge/radius ratio of the cations. 相似文献
14.
Dehydroabietates with poly(ethylene oxide) chains of average m=12, 17, and 45 units [DeHab(E)
m
] were synthesized. The adsorption at the liquid-vapor interface was measured, and the adsorbed amount and critical micelle
concentrations (CMC) were determined. The foamability, the foam stability, wetting properties, and cloud points, with and
without salt content, were studied. The results were compared with common linear alkyl ethoxylates, nonylphenol ethoxylates,
and cholesterol ethoxylates. The dehydroabietic acid as hydrophobe was found to result in the same CMC as a linear dodecyl
chain. DeHab(E)45 was found to be insoluble above 400 mg/L, but the surface tensions at lower concentrations were similar to those of the C11–13E38–40 surfactants, which exhibit CMC in aqueous media. The foaming behavior of the DeHab(E)12 and DeHab(E)17 surfactants was about the same as for common linear C
n
E
m
surfactants. The foamability as well as the foam stability increased with ethylene oxide (EO) chain length. The cloud point
was depressed by increased salt concentration and increased with the number of EO units in the head group. The cloud point
was significantly lower than for the corresponding surfactant with a dodecyl chain with similar EO chain length. The wetting
results, obtained by measuring the contact angle at similar surface tensions, indicate that surfactants of the DeHab(E)
m
type are more efficient wetting agents than both disaccharide sugar surfactants and C
n
E
m
type surfactants. 相似文献
15.
Five mycolic acids [2-alkyl-3-hydroxy FA: R1C*(OH)C*HR2COOH] were synthesized using acyl chlorides with alkyl chains of different lengths (total carbon numbers of mycolic acids,
12, 16, 20, 24, 36). The relationship between the chemical structures of the mycolic acids and their surface-active properties
was determined. The acids were synthesized in three steps: (i) dimerization of acyl chloride into alkyl ketene dimer, (ii)
selective reduction of C=C to C-C by hydrogenation, and (iii) β-lactone ring cleavage under alkaline conditions. The yields
of C12-, C16-, C20-, C24-, and C36-mycolic acid were 72, 73, 73, 73, and 73%, respectively. The critical micelle concentrations (CMC) of C12-, C16-, and C20-mycolic acid were 2.2×10−4, 1.36×10−4, and 7.4×10−5 M, respectively. As the carbon number increased, the surface tension at the CMC value was also lower; the values for C12-, C16- and C20-mycolic acid were 46.54, 43.59, and 41.57 dyn/cm, respectively. The emulsifying activities of mycolic acids were determined
for n-tetradecane, n-hexadecane, cyclohexane, and diesel oil. The results showed that C12-mycolic acid was the best emulsifier for diesel oil, C16-mycolic acid was the best emulsifier for n-tetradecane and n-hexadecane, and C20-mycolic acid was the best emulsifier for cyclohexane. This study showed that mycolic acids having, surface-active properties
can be chemically synthesized for potential applications in the detergent/cleaning material industries, for example, in oil
spill cleanup, oil recovery, textiles, pharmaceuticals, and cosmetics. 相似文献
16.
Micellization of Anionic Sulfonate Gemini Surfactants and Their Interactions With Anionic Polyacrylamide
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Ruijuan Wang Haitao Yan Wenmin Hu Yanhong Li Zikun Mei 《Journal of surfactants and detergents》2018,21(1):81-90
Anionic sulfonate gemini surfactants 8‐s‐8(SO3)2 and 12‐s‐12(SO3)2 (s = 3, 6) were synthesized, and their micellization in aqueous solution at 25.0 °C and pH 9 was investigated. The results show that the critical micelle concentrations (CMC) of 8‐s‐8(SO3)2 are more than 2 orders of magnitude larger than those of 12‐s‐12(SO3)2, but the spacer length has a relatively small impact on the CMC. Moreover, the interactions of n‐s‐n(SO3)2 (n = 8, 12; s = 3, 6) with anionic polyacrylamide (PAM) at 25.0 °C and pH 9 were investigated using surface tensiometry, rheolgy, and scanning electron microscopy (SEM). The results indicate that the surface tension and rheological properties of PAM depend on the concentration of n‐s‐n(SO3)2. Below the critical aggregation concentration of C1, surface tension is sharply reduced, the surface tension of n‐s‐n(SO3)2/PAM is lower than n‐s‐n(SO3)2 alone, but viscosity is almost unchanged with increasing Cn‐s‐n(SO3)2. Above C1, surface tension reduces very slowly until the saturated concentration of C2 is reached. Above C2, surface tension rapidly reduces until CM is attained, suggesting free n‐s‐n(SO3)2 micelles begin to form. In the region of C1–CM, the viscosity significantly increases. Above CM, surface tension is basically unchanged and these curves coincide with those of the single surfactant system. Moreover, the viscosity is almost constant. The SEM images indicate that fibrous aggregates are formed below C1, then transformed into multilayer fibrous aggregates above C1, and further into fiber‐braided‐structured and spider‐web‐structured aggregates above CM. The variation of viscosity is closely associated with the transformation of aggregates. 相似文献
17.
A series of cleavable aryl sulfonate anionic surfactants were synthesized from cyanuric chloride, aliphatic amine and H-acid
mono sodium salt. Their structures were identified by 1H NMR, Infrared Spectrum (IR) and Elementary Analysis (EA). Their critical micelle concentrations (CMC) in aqueous solutions
at 25 °C were determined by a steady-state fluorescence probe method and a surface-tension method. With the increasing length
of the carbon chain, the value of their CMCs and surface tensions under CMC (γ
CMC) initially decreased and then reached a minimum (respectively 2.63 × 10−5 mol L−1 and 28.29 mN m−1) when the carbon number was 10. The CMC and γ
CMC then increased when the carbon number was increased to 12. The results showed that, compared with sodium dodecyl benzene
sulfonate (SDBS), such kinds of surfactants have much lower surface adsorption amounts and greater molecular areas on the
aqueous surface.
相似文献
Zhiyong HuEmail: |
18.
Deepti Tikariha Birendra Kumar Namrata Singh Kallol K. Ghosh Pierluigi Quagliotto 《Journal of surfactants and detergents》2011,14(4):555-562
The micellization behavior of gemini surfactants i.e. alkanediyl-α,ω-bis(cetyldimethylammonium bromide) (C16-s-C16,2Br− where s = 3, 4, 10) in 10% (v/v) ethylene glycol solution was investigated by surface tension and conductometric measurements at
300 K. The critical micelle concentration, degree of micellar ionization, surface excess concentration, minimum surface area
per molecule of surfactant, surface pressure at the CMC and Gibbs energy of adsorption of the dimeric surfactants have also
been determined in the presence of different salts (NaCl, NaBr and NaI). The critical micelle concentration and degree of
micellar ionization values decrease significantly in the presence of sodium halides and follows the sequence NaCl < NaBr < NaI.
The free energy, enthalpy and entropy of micellization of dimeric surfactants in 10% (v/v) ethylene glycol solution were determined
using the temperature dependence of the critical micelle concentration. The standard free energy of micellization was found
to be negative in all the cases. 相似文献
19.
Preparation,surface-active properties,and antimicrobial activities of bis-quaternary ammonium salts from amines and epichlorohydrin 总被引:1,自引:1,他引:1
A series of new cationic surfactants, bis-quaternary ammonium salts, were prepared from tert-alkylamine and a product of the reaction of epichlorohydrin with decyl- and dodecylamine, and their surface-active properties
were measured. Specifically, the critical micelle concentration (CMC), effectiveness of surface tension reduction (γCMC), surface excess concentration (Γ), area per molecule at the interface (A), and standard free energies of adsorption (ΔG
ads
o) and of micellization (ΔG
mic
o) were determined. All these surfactants showed good water solubility and low CMC, more than one order of magnitude lower
than those of corresponding mono-alkylammonium salts. They also showed good foaming properties but worse wetting capabilities.
Many of these compounds had antimicrobial activities against gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis) and yeast (Candida albicans), but they were not active against molds. 相似文献
20.
Synthesis and Physico-Chemical Properties of Sodium 3-Oxo-2-(3-(4-sulphonatophenyl)triaz-2-enyl)octadecanoate Anionic Surfactant
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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 (ΔG°mic, ΔH°mic and ΔS°mic) and adsorption (ΔG°ad, ΔH°ad and ΔS°ad) 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