Comparison of Properties of Anion-Exchange Cottons in Fabric Form

Abstract

The effects of the substitution of various types of amino groups in cotton on the crease recovery properties have been investigated. The potentiometric titration curves of the various aminized cottons have been used to differentiate the presence of quaternary ammonium groups (strong-base anion exchangers) from the presence of primary, secondary, or tertiary amino groups (weak-base anion exchangers). Weak-base anion exchange cottons have been quaternized by treatment of cotton containing tertiary amine groups with methyl iodide and with epichlorohydrin. In addition, strong-base exchangers have been prepared directly by a one-step process in which cotton pretreated with a base is reacted with a mixture of epichlorohydrin and a tertiary amine at a 3: 1 molar ratio. Weak-base aminized cottons containing primary amino groups have been reacted with epichlorohydrin in the presence of an aqueous base to form cottons of improved dry-and high wet-crease resistance. Only those quaternized cottons prepared from the reaction of pure epichlorohydrin on cottons containing tertiary amine groups possessed both high dry-and improved wet-crease recovery properties. Equations are given to illustrate types of reactions investigated and mechanisms of reactions.

Chemical modification of cotton to improve fibre dyeability

“…Some of the developments in the field of cationisation of cotton to improve its dyeability towards anionic dyes have been reviewed [7]. The most common approach is via reaction of various types of fibre-reactive substituted amino compounds with cotton [8][9][10][11][12][13][14][15][16]. By introducing amino groups, the cellulosic fibre will be cationised giving a high substantivity for anionic dyes due to the Coulombic attraction between the positive charge on the fibre and the negative charge on the anionic dyes.…”

Immobilization of residual dyes onto ion-exchanger cellulosic materials

“…Among the various groups of dyes, acid dyes are the most frequently used in dyeing substrates such as wool, silk, nylon, and leather 27. Due to the anionic character of these dyes, cationized cellulose has been used for improving the dyeability of cotton fibers28–30 and the adsorption of the wasted dyes 31–33. Such cationized cellulose is prepared by the reaction of epoxy propyltrimethylammonium chloride (EPTMAC) which links quaternary ammonium sites to the cellulose.…”

Effect of solvent induced hydroxylation of cyanoethyl group on dye uptake of cotton fabrics

“…It has been reported [2][3][4][5][6][7] that the cotton fabric is treated with various chemicals prior to dyeing to improve its dyeability with reactive dyes and to facilitate dyeing at neutral pH. 8,9 In our earlier study 10 we have dealt with the effect of solvent-induced partial cyanoethylation and hydroxylation of cyanoethyl group on the physio-chemical properties of cotton fabric and found that hydroxylation of cyanoethyl group results in formation of amide group.…”