Dyeing polypropylene with anthraquinone derivative disperse dyes

Unmodified polypropylene has heretofore proven almost impossible to dye. The objective of this research was to evaluate a series of prototype compounds for a new class of dyes adapted especially for polyolefins. The effect of lengthening the alkyl chain hydrophobic functionality of the dye was tested. Two distinctly different polypropylene fabric types were used for the dyeings. Dye/substrate interactions were explored in preliminary dyeings.

Data for both sorption and rate of dyeing isotherms were gathered via spectroscopic analysis of exhausted dyebaths. Sorption isotherm studies revealed a Nernst isotherm for the series of dyes evaluated. Dye yield on the fiber was as high as 90% and deep shades were obtained. The dyed fabrics were characterized through colorimetry, fastness testing, and optical microscopy.