Thermal-oxidative degradation of some ion-exchange resins containing phosphorus

Abstract

Some phosphorus-containing cation-exchange and amphoteric ion-exchange resins have been studied by thermal analysis methods. The mechanism of decomposition of the phosphorus-containing ionizable groups has been found by a combination of the methods of thermal analysis, infrared spectroscopy, paper chromatography and elementary analysis of the residue and of the products of thermal-oxidative degradation. It was found that the amphoteric resins decompose by a mixed mechanism, comprising reactions of free phosphonic acid groups and of phosphonic acid groups in the internal-salt form.