Hetero-functional azo reactive dyes applied on cellulosic fabric and dyeing conditions optimization to enhance the dyeing properties

Abstract

New dyestuff moieties are introduced in the textile industry to upgrade the quality and aesthetic properties of dyed fabric. To contribute to this research endeavor, the current project was conducted for the dyeing of cellulosic fabric via new hetero-functional reactive dyes R1 and R2 synthesized in our previous study. Optimization of different process variables (temperature, salt, and alkali concentration) and their interactive study for exhaust dyeing was explored and delineated based on a statistical tool response surface methodology. Results divulged that both dyes displayed maximum exhaustion and fixation at a temperature of 61.50°C on the cellulosic fabric. Reactive dye R1 exhibited 87.62 (±3) exhaustion and 82.85 (±3) fixation percentage at their optimum salt (29.07 g/L) and alkali (32.55 g/L) dosage while R2 displayed 81.50 (±3) exhaustion and 77.21 (±3) fixation at its optimized salt (32.55 g/L) and alkali concentrations (22.84 g/L). All process variables showed a positive and synergistic effect on the dyeing properties. Enhanced exhaustion and fixation percentage of R1 as compared to R2 may be accredited to greater planarity and less steric hindrance of R1. Both dyes presented superb color buildup showing good to excellent color fastness on cotton fabric. Future perspectives of the current study comprised the application and assessment of dyeing parameters of these new reactive dyes on polyester cotton (PC) fabric.