Studies on carboxymethylated cellulose: Potentiometric titrations, 2

Effect of the sizes of counterions on the dissociation constant of carboxymethylated cellulose (CMC) is studied by potentiometry. Dissociation of protons from the CMC chains is suppressed with increasing size of the counterion. A good agreement is observed between the theory of Kagawa and Gregor and the experimental results accounting for the counterion size effect; a thermodynamic analysis of ΔpK supported this conclusion. Effects of concentration changes of the polyacid were also considered.