Dyeing behaviour and fine structure differences in acrylic fibres relaxed under different conditions

Fine structure differences in an acrylic fibre relaxed under different conditions have been studied in terms of dyeing behaviour. From information on the dyeing kinetics obtained at different temperatures, it was deduced that diffusion coefficient increases with degree of relaxation, while activation energy remains almost constant. Glass transition temperature tended not to vary as a function of degree of relaxation, although the temperatures measured under wet conditions or during dyeing tended to decrease slightly for substrates that were highly relaxed.