Pressure Of Polymer Solution Research Articles

Well test analysis on pressure of viscoelastic polymer solution with variable rheological parameters*

According to the behavior that the polymer solution has both the characteristics of viscosity and elastic properties, the transient flow mathe- matical model considered the viscoelasticity of the polymer solution has been established. The model, in which the variation of the rheological parameters during the seepage flow has been also taken into consideration, has been solved using finite-difference method. The type curves have been plotted. The influence of some properties of polymer solution including the viscocity, the elastic properties and the rheological parameters has been analyzed. Compared with the curves of the power-law fluid, it is shown that the pressure derivative curve considering the elasticity of the polymer solution upwarps less at the radial flow regime. Besides, it will come down as the variation of the rheological parameters, which is quite different from the case regarding them as constants. Therefore, in well test analysis on pressure of polymer solution, it’s necessary to consider the elasticity and the variation of the rheological parameters.

Virial coefficients and osmotic pressure in polymer solutions in good-solvent conditions

We determine the second, third, and fourth virial coefficients appearing in the density expansion of the osmotic pressure Pi of a monodisperse polymer solution in good-solvent conditions. Using the expected large-concentration behavior, we extrapolate the low-density expansion outside the dilute regime, obtaining the osmotic pressure for any concentration in the semidilute region. Comparison with field-theoretical predictions and experimental data shows that the obtained expression is quite accurate. The error is approximately 1%-2% below the overlap concentration and rises at most to 5%-10% in the limit of very large polymer concentrations.

Studies on Polymer Chain Dimension in Solution——Calculation of Osmotic Pressures of Polymer Solutions

Studies on Polymer Chain Dimension in Solution——Calculation of Osmotic Pressures of Polymer Solutions

The Interaction between Rubber and Liquids. V. the Osmotic Pressures of Polymer Solutions in Mixed Solvents

Abstract An expression is obtained for the free energy of dilution of a ternary mixture of polymers + two liquids by one of the liquids. This is used to consider the osmotic equilibrium between a solution of a polymer in a mixture of two liquids, and a second phase containing only the two liquids. It is shown that the osmotic behavior of the ternary solution is very similar to that of a polymer in a single liquid, and in particular that van't Hoff's law holds at infinite dilution. The distribution of the two liquids between solvent and solution is also calculated. The experimental difficulties involved in the use of mixed solvents are discussed.

The interaction between rubber and liquids. V. The osmotic pressures of polymer solutions in mixed solvents

Abstract An expression is obtained for the free energy of dilution of a ternary mixture of polymers + two liquids by one of the liquids. This is used to consider the osmotic equilibrium between a solution of a polymer in a mixture of two liquids, and a second phase containing only the two liquids. It is shown that the osmotic behavior of the ternary solution is very similar to that of a polymer in a single liquid, and in particular that van't Hoff's law holds at infinite dilution. The distribution of the two liquids between solvent and solution is also calculated. The experimental difficulties involved in the use of mixed solvents are discussed.