LINEAR AND CROSS-LINKED COPOLYMERS OF VINYLAMINE WITH VINYL PYRROLIDONE OR METHYL-METHACRYLATE - CHELATION OF COPPER

Poly(vinylamine) and linear copolymers of vinylamine (VA) with vinylpyrrolidone (VP) or methyl methacrylate (MMA) were used for the complexation of copper (II). The stoichiometry of the complex between the amino groups and copper was 4/1 in every case. Copolymers with VP are able to coordinate copper even at low VA content whereas only MMA copolymers with high VA content exhibit coordination. This effect was explained by differences in the distribution of the VA units in the two series. The capacity of these polymers towards copper is always much lower than the theoretical value calculated on the basis of the VA content and the 4/1 stoichiometry. Crosslinked polymers were prepared from the same comonomers and ethylene glycol dimethacrylate as crosslinking agent. The capacity-pH profiles of these chelating resins are close to those of the linear copolymers. Their capacity toward copper is also much less than the theoretical value.