Structural relaxation behavior of a 30% mole fraction mixture of DMSO and water

The Brillouin spectra of a 30% DMSO-water mixture are analysed at various temperatures from −80°C to +25°C.These measurements, together with the ultrasonic absorption values obtained in the literature, are used to compute the viscoelastic parameters over a large temperature range.In particular,the values of mean structural relaxation times are in good agreement with the literature but a rather broad distribution is found. This fact is confirmed by means of photon correlation technique.