An investigation on the effect of solvents into the dyeing of poly isophthaloyl meta-phenylene diamine with cationic dye

Purpose The purpose of the paper is to compare solvent efficiency in the dyeing of poly-isophthaloyl meta-phenylene diamine (preferably used as meta-aramid) fibers to get high K/S value. Poly-isophthaloyl meta-phenylene diamine due to high crystallinity is difficult to dye at ordinary dyeing conditions. These fibers share a high degree of applications in technical textiles, keeping in view its flame retardancy and mechanical properties. Replacing traditional aromatic carriers, such as o-phenylphenol, with benzyl alcohol and cyclohexanone may reduce the toxicological and environmental impacts of aramid dyeing processes. This substitution supports the development of more sustainable dyeing systems through improved chemical safety profiles and potentially lower risks to aquatic ecosystems and worker health. Design/methodology/approach Dyeing of meta-aramid fibers is optimized in this article using cationic dye, which is achieved by exploring three solvents (benzyl alcohol, cyclohexanone, N-Methyl-2-pyrrolidone). A complete design of experiments was used to investigate the effect of different solvents alone and in combination for evaluation of K/S. Findings Effect of these solvents is analyzed by K/S value, fastness properties, mechanical strength and X - ray diffraction. The high K/S value 23 was achieved using cyclohexanone solvent and 25.9 with combination of solvents. The effect of these solvents individually as well as in combination is explained in the results. Originality/value This research avoids the conventional carriers which are hazardous and used to get dye penetration. Alternatively eco-friendly solvents have been used to get high K/S value by optimization of the process by complete explanation of dyeing mechanism using fundamental chemistry.