Lipophilicity in dye-cellulose fibre binding

Abstract

Lipophilicity in cellulose dyeing has been modelled by correlations of dye structural parameter with dye affinity and lipophilic dye parameters. In a series of anionic azo dyes hydrophobic interactions in dye-fibre binding only appeared in two subseries of dyes having a coupling component with one or two sulphonic groups. Good correlations with dye affinity and lipophilic paramaters were obtained by the Multiple Linear Regression (MLR) Analysis and Principal-Component-Regression (PCRA) approach. Minimum Steric Difference (MTD) calculations suggest the presence of mainly steric and possible electronic interactions in the adsorption of anionic azo dyes by cellulose fibre. Similar calculations were performed for a series of disperse azo dyes, suggesting possible electronic and hydrophobic effects in dye-fibre binding. Dye lipophilic properties also depend on polarity and bulk terms.