Pure acrylamide in solution of water was prepared and ultrasonic velocity measurements were carried out using an ultrasonic velocity metre with a 2 MHz normal beam transducer. A path length of 40 mm was maintained during ultrasonic velocity measurements. Polymerization process was initiated by chemical means ultrasonic velocity measurements were carried out after arresting the polymerization process by suitable method and the residual monomer was estimated by spectrophotometry.

Ultrasonic velocity was found to increase linearly with time of polymerization. This is attributed to the increase in elasticity of polymer solution. The change in ultrasonic velocities at different intervals of time were compared with the residual monomer concentrations and is found to be gradual. The study indicates the usefulness of ultrasonic velocity measurements in quantifying unpolymerised residual acrylamide in polymer. Prospects for successful implementation of the measurements for on-line monitoring appear to be attractive for polyacrylamide manufacturing industries.