ABSTRACT
Potentiometric titrations of the products obtained by polyvinyl alcohol first carboxyalkylated with chloroacetic acids were conducted with LiOH, NaOH, KOH, NH4OH, N[CH3]4OH and N[C2H5]4OH in deionized water, and with mixtures of LiOH and tetraethylammonium hydroxide of varying proportions. The results were expressed in terms of the modified Henderson-Hasselbach equation pH = pKa-n log [[1-alpha]/alpha]. Appreciable shifts in the titration curves to lower pH values were observed, accompanied by increase of the calculated capacity of the polyelectrolyte, in the sequence N[C2H5]4OH < N[CH3]4OH < NH4OH < KOH < LiOH. The values of pKa [at alpha = 0.5] where alpha is the degree of neutralization and is found to increase with the size of counterion. The titration curves obtained with mixture of LiOH and N[C2H5]4OH showed that the calculated values of capacity and the position of the curves were intermediate between those obtained with solutions of the single cations