Abstract

Polyacrylamide solutions are extensively used as chemical additives or processing aids in the manufacturing of paper and paperboard products. In addition, they have been widely used in enhanced oil recovery. In this thesis, an experimental work has been carried out to provide a complete and comprehensive study of the rheological properties of polyacrylamide solutions using cone-and-plate rheometery. Polyacrylamide concentrations in the tested solutions ranged by weight from 2 to 5%. The scope of the study includes the measurements of steady-state behavior, transient shear stress and yield stress response, thixotropic, creep recovery, and dynamic responses for each concentration. The findings resulted in several conclusions regarding the rheological properties of polyacrylamide solutions. They have shown a strong shear-thinning behavior for all concentrations. The dynamic viscosity showed two different behaviors--shear-thinning region and shear-thickening region. Significant transient behavior has been observed for all concentrations of polyacrylamide solutions. The yield stress of PAM solutions increased with increasing concentrations. Three different behaviors of thixotropy test have been observed--thixotropy, antithixotropy, and time dependent. Finally, the viscous part of PAM solutions was always higher than the elastic part.