Weathering and the Resulting Chemical Changes in Some South African Merino Wools

Abstract

Differences in chemical contposition between root, middle, and tip sections of a num ber of normal crimped and of copper-deficient steely South African Merino wools have been investigated, as well as the influence of these differences on such factors as acid dye absorption, alkali solubility, and urea-bisulfite sotuhitity. In the case of normal wools the loss in cystine and tryptophan and increase in cysteic acid reveal the extent of hydrolytic and oxidative weathering damage and explain subsequent changes in solubility and dye absorption. The conclusion is reached that copper-deficiency retards fiber keratinization which can, however, continue during aging and weathering of steely wools on the animal's back, resulting in increased cross-linking. Variations in amino acid content of root and tip sections of normal and steely wools have been found.