Abstract
The mechanism of the action of several commonly used hydrotropes has been investigated in a nonionic surfactant system where the state of aggregation is determined by the solvation of the surfactant headgroups. Determination of the order parameter of the water in the lamellar phase of the system by Deuterium NMR indicated changes in the state of solvation and headgroup local order. The results indicate, in some cases, the primary mechanism of hydrotropic action involves changes in the solvation of the surfactant; whereas, the most efficient hydrotropes appear to be those which can incorporate into the most structurally sensitive region of the surfactant bilayer interior.