Surfactant aggregation in systems containing alkanolamines and fatty acids

Monomeric and dimeric anionic surfactants: A comparative study of self-aggregation and mineralization

“…On the other hand, the interfacial area per surfactant molecule (a s ) shows little change with surfactant concentration, although for GS-MEA salts, it tends to decrease slightly as surfactant concentration increases. a s values are higher than those previously reported for lamellar (L a ) liquid crystals of LA alkanolamine salts [17]; this is expected, as amphiphilic molecules are more closely packed in the low-curvature L a phase. Both the micellar radius and the specific surface areas are similar for GS and LA salts, within the same concentration range.…”

“…It should be pointed out that we also observed phase separation (precipitation) at low surfactant concentrations (i.e., below 5 wt.%) for GS-TEA. This phenomenon has been observed previously in alkanolammonium carboxylate solutions [17] and was attributed to an incomplete dissociation of the acid. In fact, no such phase separation was reported for GS-H neutralized by a strong base such as NaOH [13].…”

“…Alkanolamines also act as counterions in phospholipids; therefore; they are relevant for the study of cell membranes [16]. Nevertheless, there is not much open literature on alkanolamine surfactants [17][18][19], and to our knowledge, there is no report on alkanolamine dimeric surfactants.…”

Surfactant-Enhanced Dissolution of Phenanthrene into Water for Laminar Flow Conditions

“…The dissolution model described earlier (22) relied on fitting one parameter, the mass transfer coefficient for surfactant micelles. The diffusion coefficient of micelles, which is directly correlated to the size of micelles, has been shown to decrease with increased surfactant concentration (45,52,53). For the present flow cell study, a measured value for the micellar diffusion coefficient was obtained using a diffusion-ordered NMR technique (40).…”

Soap

“…The studies carried out by Warnheim and Jonsson showed that amine soaps are not only more soluble than the alkaline soaps in water but their phase behavior is much simpler compared with the alkali soaps. For example, triethanolamine palmitate in water forms a lamellar liquid crystal phase at 208C and no hexagonal liquid crystal phase (6,7). Research work carried out by scientists from Unilever Plc discovered very recently that significant hydrolysis takes place at room temperature for triethanolamine stearate in a 20% aqueous solution.…”