Interactions acid-soap complex

Experimental results (12) showed a transition to a lamellar liquid crystal for 14 added water molecules. Our calculations (to be reported at a later occasion) showed no discontinuity or any other indication of instability of the soap/acid water complex for the subsequent water molecules added in excess of 14. It appears reasonable to assume that the isotropic liquid/liquid crystal transition does not depend on the energy levels of the polar group interactions. The phase transition probably depends on the hydrophobic/hydrophilic volume ratio and estimations according to Israelachvili/Ninham (15) approach may offer a better potential for an understanding. 

Various associative interactions of hydrolyzable surfactants in aqueous media can play a significant role in determining the adsorption behavior of these surfactants. For example, existence of ionomolecular complexes has been shown to have a significant effect on the adsorption of oleic acid on hematite as indicated by the flotation results (Xiao, 1990). Evidence for high surface activity of mixed acid-soap was obtained by surface tension measurements of oleate solutions (Ananthapadmanabhan, 1980). The surface activity of acid-soap was estimated to be larger than that of both the corresponding acid molecule and ionic soap. Similarly maximum flotation of quartz with alkylamine observed around pH... 

Typical basic pigments include basic lead carbonate, basic lead sulfate, red lead, and zinc oxide. The soaps formed when these materials Interact, for example, with linseed oil, are oxidized in the presence of water and oxygen to form mono- and dibasic straight chain Cy to Cg acids. Materials of this type (e.g., sodium and calcium azelate and pelargonate) are known to inhibit corrosion. Inhibition is associated with formation of complex ferric salts that reinforce the oxide film. Lead salts act at lower concentration than the sodium or calcium salts (3, 41). 

The effect of alkanolamides (hand dishwashing liquids and shampoos) is difhcult to explain because they are, in fact, mixtures of free fatty acids, alkanolamine soaps, and fatty acid esters of the alkanolamine and of the alkanolamide. Nevertheless, it is reported that dialkanolamides are effective because of their ability to complex with the anionic, leading to stronger micellar interaction and, consequently, higher foam film viscosity as well as lowering the anionic s CMC [76]. The most often used are lauric/myristic mono-ethanolamides and coco diethanolamide. 

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