Thermodynamic properties of aqueous polyacrylamide solutions as a function of pressure and temperature

✍ Scribed by S. Ali; J.L. McAtee Jr; S. Claesson

• Publisher: Elsevier Science
• Year: 1985
• Tongue: English
• Weight: 441 KB
• Volume: 21
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(85)90068-0

✦ Synopsis

The viscosities of dilute aqueous solutions of polyacrylamide were measured at temperatures from 20 to 60.4 ° and pressures up to 150 MPa using a falling-body viscometer. The viscosity coefficient, ~, increases exponentially with increasing pressure at a given temperature and concentration. The rate of increase of the apparent energy of activatiom E *, with pressure becomes more rapid as the concentration of the solutions increases. Intrinsic viscosity, [rl], increases with increasing pressure at a given temperature but almost levels off at pressures above 100 MPa while the Huggins constant, kn, decreases. The Flory-Huggins interaction parameter, ×~, decreases at a greater rate with increasing pressure as the temperature decreases indicating that the effect of pressure on improving the compatability between the polymer and solvent is greater near the 0-temperature. The second virial coefficient, A2, was calculated from the intrinsic viscosity data and compared with the results obtained by light scattering technique.