Acid–base and dyeing properties of Nigerian Merino, Yankasa, and Merino–Yankasa crossbred wools

The acid–base titration curves of three wools, Merino, Yankasa, and a ⅝–⅜ Merino–Yankasa crossbred wool, grown in Nigeria, were measured at 25°C in the presence of varying amounts of sodium chloride. Amino acid analysis was carried out on these wools and correlated with the acid–base properties. The isoionic point and titration curves of Merino and the crossbred wool are similar, while those of Yanakasa are somewhat different. The acid–base behavior was interpreted by the Gibbs–Donnan treatment for the acid titrations and the pK₀¹ values for the carboxyl groups obtained, showing the existence of normal and salt-linked carboxyl groups in these wools. Dyeing tests with acidic and basic dyes have shown that the crossbred wool responds almost as well as Merino. Together with the similarity of its mechanical properties, it seems that this crossbred wool is suitable for all the textile applications for which Merino wool is normally preferred.