Synthesis of Partially Hydrolyzed Polyacrylamide and Investigation of Solution Properties (Viscosity

Copolymer of sodium acrylate and acrylamide was prepared by free radical polymerization in solution. Molecular weight was determined using Ubbleohde viscometer. Various reduced viscosity measurement tests were conducted to characterize the viscosity behaviour of partially hydrolyzed polyacrylamide. Experiments show a polyelectrolyte effect when reduced viscosity is plotted against polymer concentration. The reduced viscosity is rising in salt free solution due to dilution. Salt addition to the polymer solution presents quite different results. The polyelectrolyte effect disappeared at higher concentration of salt as a consequence of inhibiting the polyions from intramolecular expansion. The effect of different low molecular weight electrolytes on reduced viscosity of polymer solution was investigated. The intrinsic viscosity was obtained as a function of charge density (degree of hydrolysis) on the backbone of the polymer chain. It is observed that the intrinsic viscosity increases with increasing the percentage of ionic carboxyl groups on the polymer molecules. The reduced viscosity of the polymer was obtained in a solvent mixture of water and formamide.