EFFECT OF CONCENTRATION OF WATER-SOLUBLE POLYMER SOLUTIONS ON RHEOLOGICAL PROPERTIES

 This research deals with experimental study of the rheological behavior of polymer solutions. All polymers studied in this work are water soluble and used in industries as rheology control additives (rheology modifiers), these are: XC-polymer, Carboxymethyl cellulose (two types),Hydroxyethyl cellulose and Polyvinyl alcohol. The rheological properties of these polymer solutions was investigated using a Couette coaxial cylinder rotational viscometer ( Fann model 35A ), by measuring shear stresses versus shear rates (i.e. the flow curve). 55 experiments were performed with different polymer concentrations and 30 °C ( ±1 °C). By using the Solver Add-in in Microsoft Excel®,the power law flow model was found to be the best fits the experimental results. It was found that as polymer concentration increased, the flow behavior index (n) decreased and the consistency index (k) increased. This behavior reflects the fact that as polymer concentration increases, the solution become far from Newtonian. Correlations that describe the effect of polymer concentration on  n  and k  (for each polymer used in this study) was found and presented in a linear and exponential form respectively. Also it was found that XC-polymer solutions have
a higher viscosity, and its viscosity decreases much more than other polymer solutions used in this study.