Cationic ester-containing gemini surfactants as retarders in acrylic dyeing

Two ester-containing cationic gemini surfactants (esterquat and betainester types) and one stable cationic gemini surfactant with the same spacer length between the two quaternary head groups were investigated as retarding agents in acrylic dyeing with a cationic dye. The effects of surfactant concentration, time, and temperature were studied on cationic dye adsorption onto acrylic fibers. The results indicated that the presence of ester bond in alkyl tails of cationic gemini surfactants has an important role on the retarding action of dyeing process and it reduces the blocking effect. The dye adsorption kinetic at various surfactant concentrations and temperatures was studied by using different empirical models. The cationic dye adsorption on acrylic fiber showed a very good correlation with the modified Cegarra-Puente empirical model. According to the obtained activation energy values, the dye diffusion into the fiber depends significantly on the chemical structure of the used gemini cationic surfactants and their concentrations. (C) 2015 Elsevier B.V. All rights reserved.