The potentiometric titration of gum karaya aud some other tree‐exudate gums

Abstract

Abstract Potentiometric titration of gum karaya was used to determine the acid equivalent weight and the proportions of the acid groups in the salt form and the free acid form. Alkaline hydrolysis was used to determine the acyl groups attached to the gum. These determinations were also carried out with other tree‐exudate gums including gum arabic, gum jeol ( Lannea coromandelica gum) and tree‐gums from Sterculia tragacantha, Acacia sieberana, Acacia polyacantha and Albizia zygia. Potentiometric titration also showed the presence of basic groups attached to the polyanion in some gums. The variation of viscosity with pH can be correlated with the potentiometric titration curve.