Differential vapour pressure osmometry—I. Description of the method

✍ Scribed by W. Adames; W. Breuer; A. Michalczyk; W. Borchard

• Publisher: Elsevier Science
• Year: 1989
• Tongue: English
• Weight: 289 KB
• Volume: 25
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(89)90115-8

✦ Synopsis

A differential technique in vapour pressure osmosis is described. It allows accurate determination of thermodynamic parameters over a large concentration range for various temperatures. By measuring the osmotic vapour pressures between two solutions with various concentration differences and using an extrapolation procedure analogous to the Zimm-plot-extrapolation in light-scattering, the differential function of the osmotic pressure is obtained. The applicability of the method is demonstrated with the determination of the number-average molar mass of the polymer and the Flory-Huggins interaction parameters, Z~ and ~2, of the system polydimethylsiloxane/cyclohexane.