Dyeing of jute fabric with tesu extract: Part II – Thermodynamic parameters and kinetics of dyeing

172-177Thermodynamic parameters and dyeing kinetics for colouration of bleached and selectively double pre-mordanted jute fabric dyed with purified natural dye powder obtained from aqueous extract of tesu under optimized dyeing conditions have been studied to understand the physico-chemical interaction amongst dye, fibre and mordant. It is observed that this dyeing process is endothermic. Dye absorption isotherm of this particular fibre-mordant-dye system is found to be linear, following Nernst absorption isotherm. FTIR spectra of bleached, mordanted and purified natural dyed (tesu dyed) jute fabrics have also been compared. It is revealed that dyeing of selectively pre-mordanted bleached jute fabric mostly occurs through H-bond formation along with minor possibility of co-ordinated complex formation for fixation of tesu colourant on the selectively double pre-mordanted jute fibre