A salt-free, zero-discharge and dyebath-recyclable circular coloration technology based on cationic polyelectrolyte complex for cotton fabric dyeing

Abstract

Textile industry is one of the most polluting industries due to the large quantities of dyeing wastewater it generates and discharges. Herein, we report an eco-friendly and sustainable circular coloration technology based on cationic polyelectrolyte complex to realise salt-free, zero-e uent-discharge circular dyeing for cotton fabrics with a recyclable dyebath by using a typical cationic polyelectrolyte polyhexamethylene biguanide (PHMB) bonded with anionic dyes. The cotton fabrics were rst treated with PHMB and then dyed with three commercial acid dyes. Colour measurements show that the colour strength is controllable by adjustment of concentrations of both PHMB and the dyebath. The dyed fabric samples were found to have good/excellent colour levelness (< 0.49), and the colour fastness (Grade 3 ~ 5) was basically satisfactory and acceptable. The dyebath was proved to be recyclable for circular dyeing occurring at room temperature, which greatly reduces consumption of both water and heat energy for textile dyeing. Meanwhile, the dyed fabrics showed antimicrobial activity, particularly for the grampositive S. aureus, which may help reduce the healthcare-associated infections that transmit through textiles. These results suggest that cationic polyelectrolyte-based circular dyeing could provide a promising and practicable strategy to address the pollution issue caused by wastewater generated in dyeing process in the textile industry.

Poly(hexamethylene biguanide) hydrochloride (PHMB)-based materials: synthesis, modification, properties, determination, and application

“…23 Three different terminal groups derived from the side reaction have been identified in the process, among which, the amino unit reached 39%, followed by 35% of cyanoguanidine and 25% of guanidine on average. 25 O'Malley et al investigated the chemical structures of synthesized 15 N-labeled PHMB by matrix-assisted laser desorption ionization time-offlight mass spectrometry (MALDI-TOF MS). 23 Another terminal group, i.e., cyanoamine, was also identified in addition to amine, guanidine, and cyanoguanidine units, together with six types of PHMB oligomers that terminated with a combination of different end groups (Fig.…”

“…Due to its superb antibacterial activity, chemical stability, low toxicity, and reasonable cost, PHMB has been widely used in a wide variety of fields, including swimming pool sanitizers, preservatives for cosmetics, the food industry, contact lens solutions, textile goods, and medical dressings under different trademarks. [12][13][14][15][16] Historically, PHMB was also known as polyhexanide, polyaminopropyl biguanide, and polihexanide hydrochloride, etc., for various application settings with the chemical name of 1-(diaminomethylidene)-2-hexylguanidine based on IUPAC nomenclature. 17 As a well-known antiseptic and disinfectant, PHMB has been extensively outlined by some researchers just focusing on the medicinal functions [18][19][20] and/or physicochemical characteristics.…”

Novel Polyhexanide-Releasing Membranes for Antimicrobial Wound Dressings: A Critical Review

“…In addition to its use in wound antisepsis [5], PHMB has found a wide range of other applications, including: (i) disinfection of medical utensils and trays, food and non-food contact surfaces, animal drinking water, recreational water, filters and toilets, (ii) preservative in contact lens solutions, cosmetics and personal care products, wet wipes, fabric softeners, and hand and mouth washes, (iii) preservation of hides and skins, (iv) anti-odor finishes in textiles and (v) antimicrobial high-pressure paper-phenol-formaldehyde resin laminates, [28][29][30]. It has also found other types of applications, such as in gene delivery [31], DNA capture for biological threat surveillance [32], antibiofouling filtration membranes [33], dental plaque control [34], cotton fabric dyeing [35], fuel cells [36], optoeletronics [37], CO2 capture and sensing [38], uranium extraction from seawater [39] and sewage dewatering [40]. As a preservative in cosmetic products, it has been considered by the European Commission's Scientific Committee on Consumer Safety (SCCS) as safe for consumers up to a concentration of 0.1% [28].…”

Development of Binder-Free Pigment Inks for Direct Inkjet Printing on Cotton Fabric without Pretreatment

“…Most inkjet printing technology requires chemical pretreatment on fabric before printing to enhance performance. ,,,, Some materials need a postwashing treatment as well after printing. The pretreatment or post-treatment may generate a large amount of chemical wastewater containing alkali, urea, thickener, acid, and release agents. − …”