Application of a chitosan/nonionic surfactant mixture to wool assessed by dyeing with a reactive dye

Abstract

Chitosan application to wool is known to be associated with problems such as its weak binding and uneven distribution. In an attempt to overcome such problems, chitosan was applied from a mixture with a nonionic surfactant. A weak time interaction was observed between chitosan and the surfactant over time, resulting in changes in the conformation of chitosan in solution, which was confirmed by viscosity measurements. The presence of chitosan/surfactant association improved the application to wool, which was assessed by dyeing the treated wool with a reactive dye at 60°C. Since this technique offers the possibility of producing deeper and more vivid colours without increasing the concentration of dye used, dyeing was also carried out at 95°C, closer to practical dyeing conditions. An improvement in the fixation of the reactive dye was observed.