Ecological alternatives to conventional dyeing of cotton with reactive dyes

Abstract

Cotton dyeing is usually performed by reactive dyes by exhaustion method. Great quantities of salts and alkalis used in the formulation of dyeing bath eventually get into the watercourses and negatively affect the environment. In this work, studied are the possibilities of reducing salt and alkali concentrations in the dyeing bath in order to reduce water pollution after the dyeing process and soap washing. The obtained results show that the alternative procedures are environmentally more favorable, which is demonstrated by reduced values chemical oxygen demand. High level of dye fixation and fastness was achieved, while the colour intensity was slightly lower in comparison with standard samples.

Sustainability-Oriented Surface Modification of Polyester Knitted Fabrics with Chitosan

“…The next step is to optimize the surface functionalization techniques to incorporate the desired type and amount of the reactive functional group [19,[21][22][23]. Considering the importance of polyester as a synthetic polymer in this research, before treatment with chitosan, polyester materials can be modified by UV irradiation [23], plasma pretreatment [24,25], enzymatic treatments [26], or alkaline hydrolysis prior to treatment with chitosan to activate the surface and increase the hydrophilicity of the polymer structure [27][28][29][30].…”

“…Alkaline hydrolysis of polyester fibers in the alkali is a traditional high-efficiency pretreatment process that takes place on the surface [10,[26][27][28]. Some studies have shown that alkaline hydrolysis can improve the coating of functional polymers to form fine roughness of polyester [12,30].…”

Photochemical Stability of a Cotton Fabric Surface Dyed with a Reactive Triphenodioxazine Dye

“…The reactive dyes have the ability to form covalent bonds with the material fibers through a nucleophilic mechanism [2]. Most dyes are ecologically hazardous [3] and toxic to human health [4]. The human body comes in daily contact under any circumstance with these reactive dyes through clothing, underwear made of cotton.…”