A study on the rheological properties and viscoelasticity of PAM aqueous solutions

The rheological properties and viscoelasticity of polyacrylamide aqueous solutions used in polymer plooding are described. A low shear rotational rheometer (Low Shear 40) and a controlled stress rheometer (AR-1000) were used to determine the viscolelasticity and rheological properties of PAM aqueous solutions with different PAM concentrations at different temperatures. Experimental data show that under the action of vibration frequency, PAM solutions possess viscoelasticity, its real number viscosity (η'), real number modulus (G') and loss tagent (tgθ) are all affected by the concentration (C) and temperature (T) of the PAM aqueous solution. Low concentration PAM aqueous solutions behave as Newtonian fluids, but PAM aqueous solutions with concentrations exceeding critical concentration (C*) behave as pseudoplastic fluids. For a pseudoplastic fluid, it still has two Newtonian areas: it shows Newtonian fluid characteristics at very low and rather high shear rates (γ). Above conclusions provide theoretical basis for tertiary enhanced oil recovery research.