The kinetics of dyeing: a non-isothermal approach

Non-isothermal kinetics can prove to be an effective tool for investigating exhaustion curves. Applying non-isothermal methods of analysis to exhaustion data for disperse dyes on polyester, it was shown that the intimate mechanism cannot be covered by a unique kinetic function, as the mechanism seems to be composed of several stages, each with its own kinetics. As a consequence, the overall kinetics change with both temperature and heating rate. It is suggested that such an analysis should be performed each time before proposing kinetic functions to fit the experimental data. Nonisothermal kinetic analysis also proves the impossibility of designing temperature-raising programmes that will ensure isoreactive dyeing for a blend of two or more dyes.