Rheological properties of salt-tolerant HPAM solutions with ultrahigh molecular weight

Abstract

The rheological properties of salt-tolerant partially hydrolyzed polyacrylamide (HPAM)solutions with molecular of 2.5×107 g/mol at different concentrations were measured in steady-state shear flow mode by Haake Rheostress 150 rheometer. Three constitutive equations (Oldroyd four constant model, Guesekus model and FENE-P model) were used for describing the apparent viscosity and first normal stress difference. The apparent viscosity of salt-tolerant HPAM solutions appears a first Newtonian zone when the shear rate is approximately lower than 0.2 s−1. At high shear rate, the HPAM solutions show shear-thinning and elasticity. The results show that the FENE-P model has the best agreement between theoretical and experimental data within the available shear rate range. The material parameters are useful for numerical analysis of polymer solution flow fields.