Adsorption and dyeing properties of acid dyes on fine denier silk fibers

In this work, the surface morphology and diameter distribution of fine denier silk fiber were observed and measured. The adsorption property of acid orange 7 on the fine denier silk fiber was studied. The pseudo-first-order model and pseudo-second-order model adsorption kinetic models were employed to evaluate the experimental data. The effects of pH values and reaction temperature on the dyeing property were investigated. The results indicated that the fine denier silk fiber exhibited a uniform fiber diameter (9 µm), which is smaller than that of conventional silk fiber (16 µm). The adsorption process of the dye could be described using pseudo-second-order kinetic equations. A higher the amount of dye adsorption at equilibrium and faster adsorption rate was obtained for the fine denier silk fiber. The color strength of fine denier silk fibers was improved for the decreased pH values and increased temperature, which exhibited an excellent dyeing property.