Some Physico-Chemical Studies on the Primary and Secondary Fibers of Low-Crimp Merino Wool

Abstract

Regardless of whether primary fibers are richer in sulfur and/or more crystalline and swell less, the results in the present study on primary and secondary fibers from low-crimp Merino wools on normal nutrition show that both the wool fiber types have very similar sulfur contents and nearly identical levels of swelling in formic acid, irrespective of the marked difference in their diameters, length, and crimp frequehcy. The agreement among the sulfur contents, chemical compositions, and swelling results in the present study suggests very strongly that the structure and composition of the keratins extruded by the two follicle types are virtually identical. It is postulated that the distribution of high- sulfur (matrix) protein and low-sulfur (microfibrillar) protein in these keratin fibers must be practically the same.

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