Chemical Relaxations in Aqueous Micellar Solutions by Ultrasonic Spectroscopy. I. Alkali Metal Hexyl and Octyl Sulfates

Ultrasonic absorption studies have been performed in dilute micellar solutions of Li, Na, and K octylsulfates, Na methylhexylsulfate, and Na hexylsulfate at 40° by the pulse technique in the range 13–143 MHz. Chemical relaxations associated with micelle formation were found in each system. The single-valued relaxation frequencies were concentration independent in solutions as concentrated as twice the critical micelle concentration. The relaxation data can be accounted for in terms of monomer–micelle association–dissociation.