Dependence of Disperse Dye Diffusion on the Structure and Morphology of Orientated Heat-set Polyester Fibres

The structural parameters that predominantly influence dye diffusion behaviour in heat-set polyester fibres have been identified. Dye diffusion has been shown to depend on two factors: the volume of the accessible region (amorphous region) and the tortuosity of the dye diffusion path. The accessible region can be represented in terms of the amorphous volume per crystal, and the tortuosity can be expressed quantitatively by combining the orientation of the amorphous phase and the nature of coupling between the amorphous and the crystalline regions. An integrated model has been proposed by combining these parameters, and has shown to correlate well with dye uptake in polyester fibres heat-set under slack and taut conditions