Physical Properties of Mercerized and Decrystallized Cottons

Abstract

Yarns from samples of Pima S-1, Hopi Acala, and Coker 100 Wilt varieties were scoured, chloroform extracted, mercerized, and decrystallized with anhydrous ethylamine without tension. Breaking loads for yarns immersed in solutions when compared to those in water were essentially unchanged by ethylamine but decreased appreciably by sodium hydroxide. Untreated yarns in water showed decreases in strength with in creases in water temperature. Sodium hydroxide caused yarn to shrink in length as much as 35% but ethylamine only about 17%. Yarn shrinkages were related to in creases in cross-sectional areas of fibers and to cell sizes of the two complexes. Fiber lengths after treatments were unchanged by scouring or extraction but decreased by the sodium hydroxide and the ethylamine. Mercerization at normal length caused a reduc tion in the percentage decrease in single fiber and bundle tenacities as the gauge length was increased. Strength increases during mercerization are attributed to increased uni formity of strength along the fiber length.