ACOUSTIC RELAXATION OF AQUEOUS-SOLUTIONS OF ETHOXYLATED DIISONONYLPHENOLS

The results of measurements of the acoustic spectra of aqueous solutio ns of a series of ethoxylated diisononylphenols in the 5-1200 MHz freq uency range and 283-333 K temperature range are reported. It was shown that the fast kinetics of these systems cannot be represented by simp le monomer- micelle exchange. It was found that several relaxation pro cesses contribute to the excess absorption of sound in these systems. One of them, with a relaxation time of 10(-8) sec, is due to rotationa l isomerism transformations in ethoxy chains. The difference in the en thalpies of the conformers ranges from 36.8 to 40.2 kJ/mole. The kinet ic and thermodynamic characteristics of this process were calculated. The conformational structure of ethoxylated SF in aqueous solutions wa s discussed.