Osmotic pressure measurements on strongly interacting polymer colloid dispersions

Equipment has been developed for the determination of the osmotic pressure of small-sized particulate dispersions of polystyrene at low volume fractions. The specific conductance of the dispersion and that of a reservoir of salt, in equilibrium with the dispersion separated by a membrane, was measured simultaneously with osmotic pressure. The results are analysed in terms of a low volume fraction theory of osmotic pressure equilibrium between a colloid compartment and salt solution compartment separated by a membrane.