title: Metal-ion retention properties of water-soluble amphiphilic block copolymer in double emulsion systems (w/o/w) stabilized by non-ionic surfactants.
abstract: Metal-ion retention properties of water-soluble amphiphilic polymers in presence of double emulsion were studied by diafiltration. Double emulsion systems, water-in-oil-in-water, with a pH gradient between external and internal aqueous phases were prepared. A poly(styrene-co-maleic anhydride) (PSAM) solution at pH 6.0 was added to the external aqueous phase of double emulsion and by application of pressure a divalent metal-ion stream was continuously added. Metal-ions used were Cu(2+) and Cd(2+) at the same pH of polymer solution. According to our results, metal-ion retention is mainly the result of polymer-metal interaction. Interaction between PSMA and reverse emulsion globules is strongly controlled by amount of metal-ions added in the external aqueous phase. In addition, as metal-ion concentration was increased, a negative effect on polymer retention capacity and promotion of flocculation phenomena were produced.
authors.affiliation: Department of Polymer, Faculty of Chemistry, University of Concepcion, Concepcion, Chile.
authors.forename: Manuel
authors.initials: M
authors.lastname: Palencia
authors.forename: Bernabé L
authors.initials: BL
authors.lastname: Rivas
mesh_terms: D002104:Cadmium / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008298:Maleates / Q000737:chemistry*; D009821:Oils / Q000737:chemistry*; D010316:Particle Size; D011137:Polystyrenes / Q000737:chemistry*; D012995:Solubility; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D004655:Emulsions; D008298:Maleates; D009821:Oils; D011137:Polystyrenes; D013501:Surface-Active Agents; C521900:poly(styrene-co-maleic anhydride); D002104:Cadmium; D014867:Water; D003300:Copper