Kinetics study of dyeing bicomponent polyester textiles (PET/PTT) using environmentally friendly carriers

The biobased carriers o-vanillin, p-vanillin, and coumarin, can be used to dye poly(ethylene terephthalate)/poly(trimethylene terephthalate) (PET/PTT) bicomponent filaments at low temperature without affecting their excellent elasticity and elastic recovery. These ecological carriers, which are free from any toxic product, present an effective solution for obtaining an ecological and economical dyeing process. This paper presents a study of the effects of the kinetics when dyeing bicomponent (PET/PTT) filaments with three disperse dyes having different molecular weights at 100 °C (upon adding ecological carriers) and at a high temperature (130 °C). The physicochemical characterization of bicomponent filaments was done using several techniques, such as SEM, BET and DSC, before carrying out a modelling study. Different models (pseudo first-order, pseudo second-order, Elovich, and intra-particle diffusion models) were used to identify an acceptable dyeing mechanism. The dyeing rate constants, the half dyeing times, and the rise time coefficients were then determined and analyzed. The results of this work explain the adsorption mechanism during the dyeing process of bicomponent (PET/PTT) filaments using ecological carriers and provide an experimental foundation for future research.