Fatty carboxylates

Mercapto- benzothiazolates Dialkyl- dithiophosphates Dialkyl(aryl)- monothiophosphates Fatty carboxylates... 

Valproic acid is one of a series of fatty carboxylic acids that have antiseizure activity this activity appears to be greatest for carbon chain lengths of five to eight atoms. The amides and esters of valproic acid are also active antiseizure agents. 

Water that is bound to the surfactant aggregates plays a role in interactions with the polar groups. It was shown that micelles can bind considerably more water than is accounted for by hydration of the alkali metal ions. This was taken as evidence that the carboxylate or sulfonate groups bind water through ion-dipole interaction and/or hydrogen bonds. Fatty carboxylic acid and carboxylate groups are linked by hydrogen bonds (AHA, A(HA)2 ), A(HA)n ). These effects have been demonstrated in many other surfactant systems (Ekwall, 1969 Ekwall and Mandell, 1967 Ekwall and Solyom, 1967 Ekwall et al., 1972). 

Amidoamine or polyamidoamine curing agents have reactivity with DGEBA epoxy resins that is similar to the polyamides. However, they are lower-viscosity products and are also lower in color. Amidoamines are derivatives of monobasic fatty carboxylic acids and aliphatic polyamines. Since the amidoamines have only one amide group per molecule, they are lower in molecular weight, viscosity, and amine functionality than the polyamides. 

Laurie acid is a fatty carboxylic acid isolated from vegetable and animal fats or oils. For example, coconut oil and palm kernel oil both contain high proportions of lauric acid. Isolation from natural fats and oils involves hydrolysis, separation of the fatty acids, hydrogenation to convert unsaturated fatty acids to saturated acids, and finally distillation of the specific fatty acid of interest. 

In the selection of an appropriate corrosion inhibitor, an important consideration is the problem of adverse competition with other additives designed to adsorb on the liquid-metal interface. Extreme pressure and/or antiwear agents compete for the same sites as the corrosion inhibitor. Eatty amines are good corrosion inhibitors in this type of environment. However, their adverse effect on the performance of ZDDP additives often prohibits their use. Half esters or amides of dodecylsuccinic acid, phosphate esters or thiophosphates are frequently employed. A combination of inhibitors is sometimes used, for example, fatty carboxylic acids or the dimer/trimer analogues of the unsaturated acids, e.g. oleic, used in conjunction with an amine such as an ethanolamine or alkyl amine, or amide such as alkyl imidazoline and sarcosines, Eig. 6.7. Shorter chain carboxylic acid and amines are used as volatile corrosion inhibitors. 

Most vegetable oils (and animal fats and oils) have the triglyceride structure. Fig. 6.8, as tri-esters derived from glycerol and fatty, carboxylic, acids. The fatty acids are almost always straight chains containing between 8 and 22 carbon atoms and may be saturated, mono- or polyunsaturated. Vegetable oil compositions are normally described in terms of their fatty acid content, referring to the acid ester moieties actual fatty acids present in the oil are known as free fatty acids. 

Gebricki and Hicks systematically studied vesicular fatty carboxylic acids in 1973 (17). At pH values greater than 10, the fatty acid surfactant is fully ionized and micelles are formed. As the pH is reduced into the region 7.5 to 9, partial protonation of the anion at the surface occurs and there is a transition from micellar to vesicular structures. These vesicles are much less stable than phospholipid vesicles for example, oleic acid vesicles are stable for only a few hours, while capric acid vesicles apparently can last for a few days. The difference is thought to be due to oleic acid being unsaturated and liable to autooxidation. Fatty acid vesicles made from micelles tend to be polydisperse and are multilamellar in structure. They are, however, easy to prepare and relatively inexpensive. 

Applications. The main application of fatty carboxylates is found in the soap bars used worldwide for hand-washing fabrics (generally based on tallow/coconut oil mixtures). Water-soluble soaps are mainly used in skin cleansers (soap bars or liquids), shaving products (sticks, foams, or creams), and deodorant sticks. Water-insoluble soaps form gels in nonaqueous systems and, due to their hydrophobicity, they can be appropriate surfactants for water/oil (w/o) emulsions. 

Defoamers may comprise an ethoxylated or propoxylated alcohol, fatty alcohol, alkylamine, alkyl polyamine or fatty carboxylic acid (27). 

---