L'effet de la concentration sur les propriétés thermodynamiques du polyméthacrylate de méthyle en solution

Osmotic pressures of polymethylmethacrylate in solution in ethylene dichloride and in dioxane have been measured at 25 °C for concentrations up to 24%. In both cases, the apparent second virial coefficient, S, increases rapidly with concentration to reach a plateau at approximately 8% in polymer, and then increases monotonically as predicted by the well-known Flory–Huggins theory. The theoretical treatments of Fixman and Yamakawa on moderately concentrated polymer solutions give very good correlations with the experimental data up to the plateau region.However, both theories cannot use the same set of molecular dimension parameters in order to obtain the best fit.