Physical Properties of Chemically Modified Cottons

Abstract

Yarns from six cottons selected for their widely different inherent fiber characteristics were mercerized (1) under sufficient tension to maintain their original length, and (2) while permitted to contract freely. Fibers were removed from the yarns and were sub jected to certain physical measurements. Moisture regain, cellulose density, linear den sity, breaking load, and elongation at break were measured on either or both fibers and yarns. Samples of the different cottons were found to differ in their response to the treatment. Those samples with a low value in a property generally displayed the greatest per cent change in that property. Large differences in the properties of the fibers and yarns were associated with the condition of mercerization whether at constant length or slack. Mercerization tended to equalize differences between the properties of fibers in a sample as well as between those of different samples.

Response of Cottons to Chemical Treatments

“…The medium and conditions of growth were as described previ-ously 18 1. S factor was assayed following the method of Reese and Gilligan with the modification that 2lD-ing samples of cotton were taken and the temperature was 35°.1 ~'iscometric C.r activity was measured by the method of Thomas [7] J and the samples of a-celluloses were prepared following the procedures outlined by Jermyn [2).…”

“…chemical treatments were also functions of fibrillar orientation. 3f ercerization and other swelling treatments were carried out on single fibers [7] and on experimental yarns [2,4,8]. Several changes in fiber and yam properties were found to be related to the x-ray , angle.…”

Shrinkage of Cotton Fibers in Sodium Hydroxide Solutions and Resulting Elastic Properties

“…Grant and co-workers have made determinations of shrinkages of fibers in yarns mercerized without tension [10,11]. Two-ply yarns (16/2, or 36.9 X 2 tex) of rather low twists, each made from one )f six different cottons, were allowed to shrink freely n sodium hydroxide of 23% concentration containng a penetrant, at 23 ° C. The yarns shrank 18% to !3% (avg.…”