Characterization of dimethyl sulfoxide-treated wool and enhancement of reactive wool dyeing in non-aqueous medium

Abstract

Wool pretreated with dimethyl sulfoxide (DMSO) was characterized and its dyeing behavior in non-aqueous green solvents was investigated. Reactive dyeing of wool in deep shades is challenging because the mandatory alkaline aftertreatment to match the fastness of mordant dyes inevitably causes damage to wool keratin. The current study showed that the colorfastness-integrity dilemma could be solved by replacing water with organic solvents as the dyeing medium. Covalent fixation is predominantly favored in solvent dyeing so that excellent colorfastness is achievable at any given shade without alkali aftertreatment. Compared with aqueous dyeing, solvent dyeing was found to give 30% higher covalent fixation on average, which translated to better colorfastness (0.5–1 grade) at higher color depth (Δ K/ S = 1.3–4.9). In addition, scanning electron microscopy, X-ray diffraction and attenuated total reflection-infrared spectroscopy results indicated that DMSO pretreatment induced morphological and structural changes of wool in favor of dyeability. The findings are crucial to the phasing-out of metal-containing dyes for eco-friendly wool dyeing.

Novel Method of Ecofriendly Single Bath Dyeing and Functional Finishing of Wool Protein with Coconut Shell Extract Biomolecules

“…Percent crystallinity as obtained by X-ray measurements is defined as the ratio of areas under the crystalline peaks to the sum of the crystalline and amorphous peak areas: where K is a constant related to the different scattering factors of crystalline and amorphous phase and set to 1 for relative measures, computed by the X-ray crystallinity calculation module of the software (XRD-6100/7000 ver 7.01, with 6100 LabX Shimadzu X-ray diffractometer). The values of crystallinity, so obtained, compare well with reported crystallinity values of wool: 23.80% and 27.1% …”

Study on UV-protection and hydrophobic properties of cotton fabric functionalized by graphene oxide and silane coupling agent

“…FTIR spectra of cotton fabric, silane coupling agent KH570, GO and modified fabric samples were shown in Figure 4. FTIR spectrum of GO reveals the C = C skeletal vibrations at 1,620 cm −1 , the C–O–C in epoxide group at 1,056 and 1,225 cm −1 , the C = O stretching vibrations at 1,395 and 1,728 cm −1 and the C–OH stretching as a broad peak at 3,398 cm −1 (Pourhashem et al , 2017; Chen et al , 2016). The FTIR spectrum of modified fabric exhibits vibration bands at 3,400, 2,898 and 1,637 cm −1 , attributed to unreacted hydroxyl on graphene oxide, C-H stretching vibration and double bond absorption, respectively.…”

Experimental High-Temperature, High-Pressure Density Measurement and Perturbed-Chain Statistical Associating Fluid Theory Modeling of Dimethyl Sulfoxide, Isoamyl Acetate, and Benzyl Alcohol

“…Dimethyl sulfoxide (DMSO) is an effective solvent in chemical synthesis and reactions with industrial applications including microelectronic manufacturing, drug therapy, Li-ion batteries, textile, and herbicides . Benzyl alcohol is a useful solvent for inks, paints, lacquers, gelatin, cellulose acetate, and shellac .…”