ON THE SUBMICROSCOPIC CHANGES OF COTTON FIBERS DUE TO MERCERIZATION

Abstract

Hereunder is given a report of observations of cotton fibers performed in order to obtain the gradual changes of their surface during the process of mercerization. The fiber surface was carefully observed through an electron microscope. Conditions of mercerization is changed by the concentration of sodium hydroxide, and the time and temperature of the treatment. The following facts have been elucidated as the result:1. The deep original wrinkles, each 0.1_??_1 microns apart swell under alkali action and have a tendency to vanish rapidly. Under ordinary conditions they vanish completely.2. The larger part of cuticle layers that form the surface of raw cotton fiber are removed during the preliminary scouring process and they are completely removed under the mercerization treatment.3. The microfibrils lying within the cellulose layers swell under alkali action, giving the surface of the fiber consequence granuler or porous appearances.The surface structure mentioned in heading 3 above has been found characterictic to cotton fibers whenever they are subjected to mercerization treatment, not only being the case with scoured cotton but with raw cotton or with dewaxed cotton. What is to account for this characterstic change of the surface structure of cotton fibers? Taking into consideration the results of the experiments worked with dyestuff absorptiveness on mercerized cotton fibers, it is concluded as follows:Mercerization process presupposes alkali action. The alkali-soluble hemicelluloses within the fiber oozes out to the surfaces, there to agglutinate on them instead of being washed off.