Radiation grafting of cotton fabric for “green” dyeing with acid dyes

Abstract

Traditional textile dyeing processes produce a large amount of wastewater due to the weak interaction and low reaction efficiency between dyes and textiles. In this work, polydimethylaminoethyl methacrylate (PDMA) was successfully grafted onto the surface of cotton fabrics by radiation grafting, as proven by infrared spectral analysis. “Green” dyeing was realized via enhanced interactions between the cotton fabrics and dyes, increased dyeing rates, and reduced organic matter in the wastewater. The effects of the concentration of the monomer and absorbed dose on the grafting rate were systematically studied. A modified cotton fabric was dyed with three primary-color acid dyes (acid red 18, acid blue EA, and acid yellow 23), and the influence of the concentration of the dye on the dyeing rate was studied. The washing wastewater was analyzed. The results showed that the dye utilization was high and the chemical oxygen demand (COD) of the wastewater was lower than the direct emission limit of the national standard using this new method of dyeing. This method is expected to play a significant role in reducing pollution in the dyeing industry.

Keywords

• radiation grafting
• cotton coloration
• acid dye
• wastewater