Effect of association on the gelation of aqueous poly (Nvinyl2pyrrolidone) solutions with y-rays

Abstract

In this study gelation of dilute aqueous poly(Nvinyl2pyrrolidone), PVP, solutions with y-rays is investigated. The gelation dose is found to increase with the addition of guanidine salts to polymer solutions. The mechanism responsible for the increase in gelation in guanidine sulfate is shown to be mainly due to the changes in the configurational behaviour of PVP. Since there was no change in viscosity-concentration relation of PVP in guanidine chloride solutions, the increase in gelation dose in the presence of this substance is explained as due to changes brought about in the indirect action of radiation by chloride ions.