Abstract
The derivatives of sodium 1-phenylazo-2-hydroxy-6-naphthalenesulfonate, some of which contains fluorine atoms, were prepared and their sorption behavior by a nylon 6 film was investigated. For all the dyes used, the amount of dye sorbed increased with sorption time, and equilibrium sorption was not established even after the sorption for 7 days at 333-363K (pH=3). The analysis of the sorption isotherms based on the dual sorption mechanism gave the partition coefficients and the parameters for the Langmuir type sorption. The former was dependent on the sorption time, while the latter was not. The thermodynamic parameters for the Langmuir type sorption were greatly influenced not only by the kinds of the substituents but also by their position. It was possible to explain such effects of the substituents by using Hammet's rule.
