Osmotic Pressures of Polystyrene, Poly-p-chlorostyrene and Poly-o-chlorostyrene Solutions

Abstract

Abstract Second virial coefficients for polystyrene (PS), poly-p-chlorostyrene (PPCS), and poly-o-chlorostyrene (POCS) were determined in various solvents by osmotic-pressure measurements. Free-energy parameters, χ, were estimated from the values of the second virial coefficients. It was shown that the values of χ in each solvent at 30°C became larger in the following order: PS, POCS, PPCS in toluene; PS, PPCS, POCS in chlorobenzene; PPCS, PS, POCS in n-butyl acetate. It was indicated that, in addition to the effect of intermolecular forces, another parameter related to the stiffness of the polymer chains should be considered in order to discuss the thermodynamic properties of polymer solutions. It was shown that the values of χ for two polychlorostyrenes in n-butyl acetate increased with an increase in the temperatures, unlike the behavior of PS in the same solvent.