Nuclear magnetic resonance of aqueous solutions of alkylpolyoxyethylene glycol monoethers

Abstract

Increasing the concentration of alkylpolyoxyethylene glycol monoethers in water results in an upfield shift of the water proton signal and a decrease in the longitudinal relaxation time. These effects have been discussed in terms of perturbation of the hydrogen-bonded solvent structure. Variable temperature experiments have revealed no discontinuities in the temperature coefficient of either the water chemical shift or the relaxation time in passing from the mesomorphic phase state to isotropic solution. The change in the chemical shift at phase boundaries has been shown to be associated with long-range order in the mesomorphic phases. It is concluded that in these systems the extent of motion and hydrogen bonding of the water molecules is independent of the nature of the phase, and determined only by the temperature and composition of the system.