Dyeing of Polypropylene Fibers with Disperse Dyes by Supercritical Carbon Dioxide

Polypropylene fabrics were dyed under various conditions by supercritical carbon dioxide technology. Amounts of dye absorbed by polypropylene fibers were calculated from the visible spectrum and penetration of dye was observed by microscopy.The result showed dye had diffused into fibers and dye uptake values of carbon dioxide dyeing obtained from visible analysis were much higher than that of water. X-ray and DSC analysis indicated that dyeing behavior of polypropylene with disperse dyes obeyed the free volume model. No obvious damage had happened while fabrics dyeing at 120°C in accordance with the TGA and mechanical properties test. Wash fastness was the major problem to be necessary to overcome on this dyeing method.