Studies of N-Dodecyllactobionamide, Maltose 6‘-O-Dodecanoate, and Octyl-β-glucoside with Surface Tension, Surface Force, and Wetting Techniques

Abstract

Three different types of sugar surfactants, octyl-β-glucoside, maltose 6‘-O-dodecanoate, and N-dodecyllactobionamide have been investigated to examine the effect of the structure of the sugar headgroup on the adsorption to liquid/vapor and solid/liquid interfaces using a number of techniques (surface tension, surface force apparatus, MASIF, and wetting). It was found that all the surfactants form monolayers when adsorbed to a hydrophobic interface at high concentrations. Increased headgroup flexibility leads to the adsorption of higher amounts on both the liquid/vapor and solid/liquid interfaces, resulting in a higher van der Waals attraction between two such monolayers. Increased hydrogen bonding within layers of more flexible surfactants is suggested to explain this difference. The most flexible surfactant, N-dodecyllactobionamide, is the least efficient wetting agent with the highest γSL. The behavior of the receding contact angles indicates the importance of intralayer hydrogen bonds between larger an...