Abstract:

An amphoteric poly(acrylamide／2-acrlamido-2-methylpropane sulphonic acid／vinylamine)(poly(AM／AMPS／VAm)) with strong absorbability of copper(II) ions was prepared by Hofmann degradation. First, the poly(AM／AMPS) was synthesized by inverse emusion polymerzation using AM and AMPS as monomers. Second, the partial  amide groups of the poly(AM／AMPS) were transformed to amine groups by the Hofmann degradation in the inverse emusion to obtain amphoteric poly(AM／AMPS／VAm). The effects of copolymerization and Hofmann degradation on their properties were discussed. The amine groups were confirmed using a FT-IR spectroscopy, and their amination value was calculated by the conductivity method. The influencing factors of removing the copper(II) ions in the simulated environment of the wastewater were investigated, such as reaction time, reaction temperature, pH value,  concentration of the copper(II) ions and the amount of products. The products before and after absorbed Cu²⁺ were characterized by SEM. The results indicated that the amphoteric poly(AM／AMPS／VAm) were of significant utility to remove the copper(II) ions.

Key words: acrylamide, inverse emulsion, Hofmann degradation, copper(II) ion, 2-acrlamido-2-methylpropane sulphonic acid