Dyeing behavior of swollen cotton fibers and swelling mechanisms of intra‐ and intercrystalline swelling agents

摘要

AbstractDyeability was used to study the swelling mechanisms of intra‐ and intermicellar swelling agents on cotton cellulose. Reactive and direct dyes were used for dyeing, and zinc chloride, ethylenediamine (EDA), and morpholine were used for swelling reactions. Changes taking place in the accessible regions as a result of swelling were determined by moisture regain, acid hydrolysis, formylation, and the lateral order distribution in the fiber structure. The results indicate that the intracrystalline swelling agents, viz., zinc chloride and EDA, induce specific changes in the accessible portions of the fiber. The accessible portion produced by the inorganic swelling agent has a more open structure than the disordered region produced by the EDA treatment. The distinctive nature of the accessible portions in swollen cotton fibers treated with the two reagents was reflected in all the properties studied. This was attributed to the different mechanisms of swelling and decrystallization of cotton fibers by zinc chloride and EDA. Morpholine was shown to bring about considerable changes in the accessible portions of the cotton fiber which were responsible for increased dyeability with reactive dyes, and was also shown to increase the amount of “truly” accessible regions by breaking the “imperfect crystals” in the disordered regions as well as on the surface of cry