Effect of low-frequency ultrasonic waves on aqueous solutions of condensed phosphates

Abstract

High-molecular metaphosphate undergoes a true fission when aqueous solutions are subjected to the action of ultrasonic waves of low frequency. There is a marked decrease in the viscosity which is permanent, and diminution in the end-group titration. The fission of the molecule is attended by a slight increase in the conductivity of the solution. There is also an increase in the pH. Practically the same amount of phosphate dialyzed out of the control and the irradiated solutions, indicating that, under the conditions of irradiation employed, low-molecular dialyzable compounds are not formed in significant quantities. The rate of degradation of metaphosphates increases with the increase in the weight-average molecular weight. Pyrophosphate, tri- and tetrapolyphosphates, and tri- and tetrametaphosphates do not undergo any significant degradative changes during ultrasonic irradiation. Estimation of orthophosphate by the isobutyl alcohol extraction method indicates that low-frequency ultrasonic irradiation does not split orthophosphate from metaphosphate.