EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Cotton is a predominant raw material in the textile industry. One of the most demanding procedures for the textile industry is dyeing of cotton fabrics with reactive dyes, since traditional dyeing processing leads to substantial environmental impacts, through the discharge of a highly colored and saline dyebath. This can be attributed to the high electrolyte concentrations, such as sodium chloride, needed to overcome the repulsive forces between the negative charges of cellulose fibers surface with the ionic species of dyes.
The most important contemporary challenges is the eco-friendly modification of cotton textiles to achieve a greener dyeing approach. To this end, the present study focuses on the water-based modification of cotton fabrics with cationic polymers, in order to achieve the charge inversion of cotton fabrics’ surface, allowing for a greener dyeing process, bypassing the use of electrolytes. The modification of cotton and the dyeing of the thus-modified cotton fabrics through water-based procedures at ambient temperature and salt-free conditions were followed by a variety of techniques, including UV-Vis spectrometry for the polymer or dye exhaustion and ζ-potential measurements of the net charge of cotton surface. In addition, characterization of the modified fabrics at molecular level by application of Raman as well as XPS spectroscopy revealed the physicochemical processes associated with the modification and the related modification kinetics.
This effective salt-free dyeing procedure, well-comparable to the traditional dyeing process, is an eco-friendlier way to overcome significant environmental problems, providing considerable benefits in industrial application such as elimination of electrolyte and significant savings in process costs.
Acknowledgement: This research has been co-financed by the European Union and Greek national funds through the Operational Program Competitiveness, Entrepreneurship and Innovation, under the call RESEARCH–CREATE–INNOVATE (project code: T1EDK- 03073)».