Fatty acids, alkali metal cation

A better method for studying the alkali metal cation-soap anion interaction on the surface, according to Weil (58), is to assume a similarity between surface behavior and solution behavior and to use the activity coefficient of the solute in the solution as the parameter to account for surface behavior. By plotting activity coefficients as a function of the molality for the salts of the alkali metals (7, 26), the resulting order of the curves of the weak acids (formates, acetates, hydroxides) is the reverse of that found for the strong acids (chlorides, bromides, nitrates, chlorates, sulfates). The activity curves of the acetate salts can be used as the counterparts for the long-chain fatty acid salts, while those for the chlorides can be the analogs of the alkyl sulfates. The scheme is speculative in that the fatty acid and alkyl sulfate salts micellize, and acetate and chloride do not. 

Adams, J. and Gross, M. L. (1987) Tandem mass spectrometry for collisional activation of alkali metal-cationized fatty acids a method for determining double bond location. Anal Chem., 59, 1576-82. 

A Naegeli-type amylodextrin of DP 21 and containing one branch-point in each molecule has been prepared from waxy corn starch. The adsorption of monobasic fatty acids from n-hexane on to dry amylose has been found to follow Langmuir s adsorption isotherm. Changes in the physical properties of a potato starch with a high content of phosphate in the presence of cations have been described. Alkali-metal cations produced an increase in the viscosity of solutions of this potato starch, whereas alkaline-earth-metal cations initiated a two-step swelling process and lowered the viscosity. 

Results from detailed studies of alkali metal cation transport across supported liquid membranes by fatty acid carriers are revealed by Kocherginsky in Chapter 5. An analytical expression for the transmembrane transport in this multi-step process is presented and good agreement between theory and the experimental data is obtained. 

Facilitated Transport of Alkali Metal Cations Through Supported Liquid Membranes with Fatty Acids... 

Acyclic oligoamides, 167-168,170/ Advancing front model, description, 116 Alkali metal cation facilitated transport through supported liquid membranes with fatty acids electrogenic processes, 79-81 electroneutral transport, 76-80 experimental description, 77 kinetics, 81-85... 

Although fatty acids are relatively weak acids, they readily form salts with metal cations or organic bases, most easily with alkali metal cations and with ammonia. These compounds are called soaps. 

Heimann and Vogtle [38] synthesized triesters of glycerol with different ether carboxylic acids with a short alkyl chain. They have found that these hydrophilic lipids, in contrast with the fatty acid glycerol triesters, give complex-ation with alkali and alkali earth metal cations in an analogy of crown ethers. 

Micellar systems (i.e.,. Shenoy 1984 Ohlendorf Brunn) as well as other colloidal systems (polyphosphates (Hunston), tri-n-butyl-tin-fluoride, e.g. Dunn Evans) come under the heading surfactants . It is necessary to differentiate soaps into anionic, cationic, and non-ionic types. Among the anionic types one can find, for instance, alkali metals and ammonium salts consisting of various fatty acids, which were... 

Another anionic surfactant is sodium dodecanoate, CnH23C02Na. It belongs to the class of sodium alkylcarboxylates, also called fatty acids or soaps. Just as with SDS in water at neutral pH, the alkali metal dissociates as a cation so that the surfactant becomes... 

In a study of the adsorption of soap and several synthetic surfactants on a variety of textile hbers, it was found that cotton and nylon adsorbed less surfactant than wool under comparable conditions (77). Among the various surfactants, the cationic types were adsorbed to the greatest extent, whereas nonionic types were adsorbed least. The adsorption of nonionic surfactants decreased with increasing length of the polyoxyethylene chain. When soaps were adsorbed, the fatty acid and the alkali behaved more or less independently just as they did when adsorbed on carbon. The adsorption of sodium oleate by cotton has been shown independently to result in the deposition of acid soap (a composition intermediate between the free fatty acid and the sodium salt), if no heavy-metal ions are present in the system (78). In hard water, the adsorbate has large proportions of lime soap. 

Charge localization after Li+- or Na -cationization of lipids seems to be at the acidic and ester functions the alkali-metal ions seem not to interact with the double bonds in an unsaturated fatly acid. The same holds for instance for Ba -cationiza-tion of fatty acids in FAB-MS [202]. The effect of wide range of metal ions, i.e., Li+, Na K Cu Sr, Ba +, Mn2+, Fe2+, Cq2+, NF+, Cu, Sc +, and... 

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