Ionic-interaction of aqueous and alcoholic poly(vinyl alcohol) in the presence of protons

Abstract

The ionic-interactions of acetic acid in H 2 O-PVOH and H 2 O-alcohol-PVOH solvent systems were studied at different temperatures by the viscosity method. The viscosities of the poly(vinyl alcohol) (PVOH) were increased with increasing concentration of PVOH and decreased with the increasing concentration of acetic acid. The viscosity data were used to evaluate the ion-ion interactions and ion-solvent interactions in terms of the A and B coefficients of the Jones-Dole equation, respectively. The negative values of the B-coefficient increased with increasing temperature, showing that the acid behaves as a structure breaker in PVOH-solvent mixtures and consequently, the values of the A-coefficient were decreased with increasing temperature. Thermodynamic parameters, such as energy of activation (E a *), Gibbs energy change of activation (∆G*) and entropy change of activation (∆S*) were also calculated as a function of the acid (CH 3 COOH) concentration, PVOH composition, alcohols and temperature.