Plasma induced physico-chemical changes & dyeing behavior of wool fabrics

摘要

This study focused on the effect of plasma treatment on physical and chemical properties of wool fabric and its relation to exhaustion of Isolan Yellow K-GLN (1:2 metal complex dye) in isotherm dyeing. In this study surface morphology and scale height of wool fibres was studied using atomic force microscopy (AFM). It was found that, plasma treatment partly removes the epicuticle and thus scale height reduces. Change in the surface chemistry was studied using attenuated total reflectance (ATR), it was found that the hydrophobic layer of 18-methyl eicosanoic acid (18-MEA) was removed and hydrophilic groups like cysteic acid (-SO_3H) were introduced on the wool fibre surface after plasma treatment. Force distance spectroscopy (FDS) was studied to find adhesion forces between AFM tip and fibre sample to measure change in hydrophilicity. It was found that after plasma treatment hydrophilicity increases many folds as compared to untreated wool fabric. Wetting time was also studied and it was found that, untreated fabric sample is non-wettable and after plasma treatment wetting time reduces to few seconds. Exhaustion of dye was studied using UV/VIS spectrophotometer; the untreated wool fabric takes 40 min to reach maximum exhaustion i.e. 97%, while 5 min plasma treated sample achieves the same exhaustion in mere 15 min time.