Abstract

RIVAS, BERNABÉ L; PEREIRA, EDUARDO; YANEZ, FERNANDO  and  MORENO-VILLDOSLADA, IGNACIO. EFFECT OF POLY(ACRYLIC ACID) IN THE METAL ION BINDING ABILITY OF POLY(SODIUM 2-(N-ACRYLAMIDO)-2-METHYL-PROPANESULFONATE). J. Chil. Chem. Soc. [online]. 2007, vol.52, n.4, pp.1288-1290. ISSN 0717-9707.  http://dx.doi.org/10.4067/S0717-97072007000400003.

The binding of Cu²⁺, Cd²⁺, Co²⁺, Pb²⁺, Zn²⁺, Ni²⁺, Cr³⁺to poly(sodium 2-(N-acrylamido)-2-methyl-propanesulfonate) (PAMPS) in the presence of poly(acrylic acid) (PAA) is studied by diafiltration. It is found an unusual behavior for the polyelectrolyte PAMPS, since it binds irreversibly a fraction of metal ions, while the rest of the ions are eluted form the diafiltration cell without interacting with the polyanion. At pH 3, and in the presence of PAA, the fraction of metal ions bound to the polymer decreases, as the sulfonate molar fraction with respect to the carboxylate groups decreases. A copolymer composed by sodium 2-(N-acrylamido)-2-methyl-propanesulfonate and acrylic acid showed the same binding ability than a mixture of PAMPS and PAA under the same relative sulfonate / carboxylate composition

Keywords : counterion binding; water-soluble polymers; metal ion interactions.