Scattering in polymer solutions: Determination of osmotic properties in the concentrated regime

✍ Scribed by Ferenc Horkay; Anne-Marie Hecht; Halina B. Stanley; Erik Geissler

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 362 KB
• Volume: 30
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(94)90162-7

✦ Synopsis

Concentrated solutions of poly(vinyl acetate)/toluene and poly(dimethyl siloxane)/octane were investigated in the polymer volume fraction range 0.08 ~ ¢ ~< 0.5 using small angle X-ray scattering. As the concentration increases the polymer-polymer correlation length deviates increasingly from the prediction of simple scaling theory. The osmotic compressibility governing the scattering intensity extrapolated to zero angle I(0) is satisfactorily described by a Flory-Huggins type equation containing an interaction parameter of the form ;C + w~o. The coefficients of the interaction parameter are found to be PVAc/toluene: X = 0.445 _+ 0.005, w = 0.153 _+ 0.01 i PDMS/octane ~ = 0.318 _+ 0.009, w=0.157+0.020.