No abstract

The sorption behavior of sodium 1-phenyl-2-hydroxy-6-naphthalenesulfonate and its deriva tives by a nylon 6 film was investigated in order to elucidate the effects of fluorine atoms. For the deriva tives, the amount of dye sorbed increased with time, and equilibrium sorption was not established even af ter the film was soaked in the aqueous dye solution for 7 days. The sorption isotherms obtained were in terpreted by considering the dual sorption mechanism which is composed of partition and Langmuir type sorption. The partition coefficients were dependent on the sorption time, while the parameters for Lang muir type sorption were independent. The thermodynamic parameters calculated from the temperature de pendence of the intrinsic binding constants for Langmuir type sorption were greatly influenced by the in troduction of a trifluoromethyl and methyl group into the dye molecule. This result is discussed in consid eration of hydrating water molecules around the dye anions.