Oxyethylene chain length affects the physicochemical properties of sugar-based anionic surfactants with phosphates groups

In this study we prepared a series of novel sugar based anionic-polyoxyethylene stearyl ether surfactants through reactions of propylene glycol dextrin with oxirane-containing polyoxyethylene stearyl ethers and phosphorus oxychloride. These surfactants, which contain polyoxyethylene chains and sodium phosphonate groups as hydrophilic moieties, exhibited surface activities superior to those of traditional surfactants containing only one nonpolar or hydrophobic moiety and one polar head unit. The critical micelle concentration (cmc), surface excess concentration at the surface (Gamma(cmc)) and standard free energy of micellization per mole (Delta G(m)(degrees)) of these surfactants decreased upon increasing the length of their polyoxyethylene chain. In addition, we used UV-vis spectroscopy to study the interactions of dyes with these sugar based anionic surfactants in solution, the results shows that the interaction of the dye and surfactant molecules and the type of dye-surfactant aggregate formed will depend upon chemical structure of dye and surfactant. (C) 2015 Elsevier B.V. All rights reserved.