Absorption of sulfonic acids on nylon in ethylene glycol

摘要

AbstractThe absorption isotherms of methanesulfonic acid, ethanedisulfonic acid, and R‐acid on nylon fiber were determined in water and ethylene glycol at 80°C. The saturation values of the sulfonic acids on the nylon fiber were determined by extrapolation of a reciprocal plot of the absorption isotherms. In water, the saturation values of the three acids were near the amino group content of the fiber. In ethylene glycol, the saturation values of the dibasic acids, ethanedisulfonic acid and R‐acid, were much larger than the stoichiometric quantity corresponding to the amino group content of the nylon fiber, approximately twice, though the saturation value of the monobasic acid, methanesulfonic acid, was near the amino group content. A dyeing model of nylon with polybasic dyes was proposed, in order to explain how a polybasic dye can physically saturate fixed s