EFFECT OF INORGANIC SALTS ON THE MAIN PARAMETERS OF THE DILUTE AQUEOUS POLY(VINYLPYRROLIDONE) SOLUTIONS

The effect of inorganic salts (cosolute) on the main parameters of dil ute aqueous poly(vinylpyrrolidone) (PVP) solutions, such as cloud poin ts, phase diagram, theta temperature and viscosity was studied experim entally using various concentrations of salts and said polymer at vary ing temperatures. It is shown that, thermodynamic incompatibility of a queous PVP-salts solutions strongly depends on the character of effect of salts (water-structure breakers or water-structure makers). Inclus ion of salts into aqueous PVP solution leads to decreasing of the thet a temperature and intrinsic viscosity which is caused by effect of the cosolute ions in enhancing the segment-segment interactions. (C) 1996 Elsevier Science Ltd.