How Chain Length, Headgroup Polymerization, and Anomeric Configuration Govern the Thermotropic and Lyotropic Liquid Crystalline Phase Behavior and the Air−Water Interfacial Adsorption of Glucose-Based Surfactants

Abstract

A matrix of anomerically pure glucose-based surfactants have been synthesized and their thermotropic and lyotropic liquid crystalline phase behavior, and air-aqueous solution interfacial adsorption were investigated. The surfactants, which represent the major components of the Fischer synthesis products, were the n-octyl, n-decyl and n-dodecyl homologues of alkyl α-d- and β-d-glucoside and alkyl β-d-maltoside. The matrix allowed the investigation of the effects of alkyl chain length, headgroup polymerization, and anomeric configuration on the surfactants' physicochemical properties. Increasing the alkyl chain length increases the hydrophobicity and the dispersion interaction between surfactant molecules, as one would expect, resulting in greater thermal stability of thermotropic and lyotropic phases. Phase transition temperatures are influenced significantly by the anomeric configuration in the shorter octyl derivatives, but to a lesser extent in the longer alkyl chain derivatives. The effect of increasin...