Interaction of Weak Organic Acids with Insoluble Polyamides II: Study of sorption of selected weak organic acids by nylon 610

Abstract

Sorption studies were conducted at several different temperatures for a group of compounds having or behaving as weak organic acids using nylon 610 as the substrate. Six compounds were included in the investigation—benzoic acid, o-hydroxybenzoic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, methyl p-hydroxybenzoate, and propyl p-hydroxybenzoate. The collected data permitted the evaluation for each compound of (a) the saturation value of solute in the nylon, (b) the affinity of the solute toward the plastic, (c) the standard heat of sorption, (d) the apparent diffusion coefficient and (e) the activation energy of diffusion. With the Rotinyan and Drozdov equation, it was possible to confirm that the diffusion of the solute in the plastic was the rate-determining step in the sorption process. Sorption studies were conducted at several different temperatures for a group of compounds having or behaving as weak organic acids using nylon 610 as the substrate. Six compounds were included in the investigation—benzoic acid, o-hydroxybenzoic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, methyl p-hydroxybenzoate, and propyl p-hydroxybenzoate. The collected data permitted the evaluation for each compound of (a) the saturation value of solute in the nylon, (b) the affinity of the solute toward the plastic, (c) the standard heat of sorption, (d) the apparent diffusion coefficient and (e) the activation energy of diffusion. With the Rotinyan and Drozdov equation, it was possible to confirm that the diffusion of the solute in the plastic was the rate-determining step in the sorption process.