Sodium decanoate system

The partition coefficients in the sodium perfluorooctanoate-sodium decanoate system (Table 6.16) are similar to those of the pure perfluorooctanoate system. For benzene, however, the partition coefficient was higher in the mixed system, suggesting again a different solubilization mechanism. 

A final example of the simulation of a complex system is a series of MD simulations of bilayer membranes. Membranes are crucial constituents of living organisms they are the scene for many important biological processes. Experimental data are known for model systems for example for the system sodium decanoate, decanol and water that forms smectic liquid crystalline structures at room temperature, with the lipids organized in bilayers. 

Thermodynamics of the Mixed Micellar System Sodium Decanoate-2-Butoxyethanol in Water at 25 ° C... 

In the present study, the system sodium decanoate (NaDec)-BE-water will be reported. The advantage of this system Is that It Is possible to make measurements below the CMC of NaDec (0.12 mol kg ) while this CMC Is still far from the effective CMC of BE ( 1 mol kg- ). Also, It Is possible to prepare a sllver/sllver decanoate... 

R De Lisi, G Perron, I Paquette, JE Desnoyers. Thermodynamics of micellar systems Activity and entropy of sodium decanoate and n-alkylamine hydrobromides in water. Can J Chem 59 1865-1871 (1981). 

For some spectroscopic applications lyotropic lamellar mesophases of soaps may be of great value. Lamellar liquid crystals are formed in sodium decanoate-decanol-water systems [14]. A convenient system is obtained by mixing 28 wt% sodium... 

Lake [117] used kinetic dialysis to examine the existence of cdc. The cdc of the sodium decanoate-sodium perfluorooctanoate mixed-micelle system was found to occur at a specific surfactant concentration and mole fraction. Ben Ghoulam et al. [118] determined the demixing diagram of the Neos Ftergent (a branched alkylbenzenesulfonate by surface tensiometry) and measured second critical micelle concentrations. However, a critical demicellization concentration was not observed. 

Figure 3- Snapshot from an equilibrated simulation of a smectic bilayer system sodium ions (A), decanoate ions (chain with forked end) and decanol molecules (linear chain). The projection of all atoms is given.

In recent studies, Friberg and co-workers (J, 2) showed that the 21 carbon dicarboxylic acid 5(6)-carboxyl-4-hexyl-2-cyclohexene-1-yl octanoic acid (C21-DA, see Figure 1) exhibited hydrotropic or solubilizing properties in the multicomponent system(s) sodium octanoate (decanoate)/n-octanol/C2i-DA aqueous disodium salt solutions. Hydrotropic action was observed in dilute solutions even at concentrations below the critical micelle concentration (CMC) of the alkanoate. Such action was also observed in concentrates containing pure nonionic and anionic surfactants and C21-DA salt. The function of the hydrotrope was to retard formation of a more ordered structure or mesophase (liquid crystalline phase). 

Clearly, the infrared spectra of the sodium and potassium decanoate micellar solutions are considerably different, as are their pressure dependencies. Since the only difference between these two micellar systems is the size, and thus the charge density of the counterions, the different infrared spectra must be taken as evidence that in the alkali decanoate micelles the sodium or potassium counter cations interact differently with the carboxylate groups of the surfactant molecules. 

Anionic micellar systems were found to increase the rate of the acid catalyzed hydrolysis of acetylsalicylic acid (Nogami et al., 1962), methantheline bromide (Nogami and Awazu, 1962), n-butyl acetate, t-butyl acetate, ethyl p-aminobenzoate, and ethyl o-aminobenzoate (Sakurada et al., 1967), but decreased that of methyl benzoate slightly (Sakurada et al., 1967). The acid catalyzed hydrolysis of anionic amphi-philes also generally tend to be accelerated by micellization (Table 5). The rates of the acid catalyzed hydrolyses of sodium sulfoethyl do-decanoate, sodium undecanoate, and sodium sulfobutyl caprylate are significantly greater in micellar than in non-micellar solutions while that of sodium dodecyl sulfoacetate is unaffected by micelle formation (Meguro and Hikota, 1968). 

In the decanoic acid-benzene system, Nakasuka et al. (91) found the coextraction of sodium ion with zinc(II) and cadmium(II) as the following mixed-metal decanoates ZnNaA3(HA)5 and CdNaA3(HA)a (a = 5, 7). Lead was also reported to be extracted with sodium ion [as Na2PbA4(HA)8] (95), as was cobalt (131). 

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