Modification of cotton fabrics with 2-diethylaminoethyl chloride for salt-free dyeing with anionic dyes

Abstract

A chemical modification of cotton fabrics by 2-diethylaminoethyl chloride (DEAE-Cl) was achieved, and the resulted cotton fabrics demonstrated salt-free dyeing properties with anionic dyes. Nucleophilic property of hydroxyl groups in cotton cellulose was enhanced under alkaline conditions and could react with DEAE-Cl, a chemical possessing both nucleophilic and electrophilic sites. The monolayered DEAE-grafted cotton cellulose could further react with DEAE-Cl to form multiple cationic quaternary ammonium salts (denoted as DEAE@Cotton), which are highly interactive with anionic dye molecules. The strong electrostatic interactions between the DEAE@Cotton and the dyes eliminated the use of inorganic salts in cotton dyeing process. The chemical structure and property of DEAE@Cotton were characterized and compared with untreated cotton. The DEAE@Cotton can be dyed in a salt-free system, and the dye exhaustion was faster than the conventional dyeing method due to the robust electrostatic interactions of the fabrics with anionic dyes. The dyed fabrics demonstrated outstanding color fastness under repeated washing, light exposure, and crocking. The dye adsorption process on DEAE@Cotton follows Langmuir isotherm model (R2 = 0.9667). The mechanism of enhanced dyeability was experimentally proved by treating the fabric with other anionic dyes in a salt-free system, proving the process to be environmentally friendly and cost-effective. Graphic abstract

An Investigation into the Adsorption Mechanism of Organic Anions on a New Spandex

“…Dyeing heat, △H°, represents heat change in the dyeing process. It refers to the heat generated during the transfer of 1 mol of acid dye from the dye bath to spandex in a standard state [ 19 , 20 , 21 , 22 ]. If it is greater than zero, the dyeing process is endothermic; otherwise, it is exothermic.…”

“…Measuring the dyeing rate curve: the spandex was dyed at 100 °C for 5 min, 10 min, 15 min, 20 min, 30 min, 40 min, 50 min, 60 min, 80 min, 100 min, 120 min, 140 min, respectively, in a dye bath of liquor ratio of 100:1 using 1 g/L acid leveling agent and maintaining a pH of 4.5 (acetic acid-sodium acetate: 10–8 g) [ 19 , 20 , 21 , 22 , 23 ]. The dye concentration was 2% (o.w.f).…”

Mussel-inspired polydopamine-modified silk nanofibers as an eco-friendly and highly efficient adsorbent for cationic dyes

“…R L is the separation factor for assessing whether an adsorption process is favorable (0 < R L < 1) or unfavorable ( R L < 1). 35…”

Bioinspired Bola Polysiloxane for Wettability, Breathability, and Softness in Fabrics

“…To solve this problem, the main strategy has been to change the polysiloxane molecule frame, type and content of hydrophilic substituents, and length of the active siloxane chain segment, but limited success has been obtained. ,,− The results showed that adding hydrophilic groups provides better hydrophilicity but leads to worse softness. , Thus, we see that hydrophilicity and softness are difficult to coordinate by changing the functional groups. From the biomimetic strategy, , looking at examples of superhydrophilic structures in nature offers an alternative way to solve the functional synergy of wettability, breathability, and softness.…”