Preparing chelated copolymer membrane for fabrication of Ag dendrites

A novel method to prepare Ag dendrites on the surface of polymer membranes, which was synthesized by using the soap-free emulsion copolymerization of n-butylacrylate (BA) and acrylonitrile (AN), as well as 2-methacrylic acid 3-(bis-carboxymethylamino)-2-hydroxy-propyl ester (GMA-IDA) that was used as a chelating group, is presented in this study. The characteristics of polymer membranes were investigated by Fourier transform infrared (FT-IR) spectroscopy and elementary analysis (EA). The weight fraction of the chelating group (GMA-IDA) in the polymer was 4.2% as revealed by elemental analysis. The chelating group, -N(CH₂COO^-Na⁺)₂ on the polymer was used to coordinate nickel(II) ions, whose chelating amount was estimated by an atomic absorption spectrophotometer (AA). The coordinated Ni²⁺ ions were subsequently reduced to nickel nanoparticles, which functioned as templates for growing Ag dendrites from aqueous solution of Ag⁺/poly(vinyl pyrrolidone) (PVP) aqueous solution. The phase identification of the Ag dendrites was confirmed by X-ray diffraction (XRD). Scanning electronic microscopy (SEM) showed the averaged dimension of Ag dendrites was about 2-3μm in length and ca. 100nm in diameter. Moreover, the amount of Ag dendrites increased with the decreasing PVP concentration present in the aqueous solution. The energy dispersive X-ray spectrometer (EDX) reveals that the formation of the Ag dendrites was chiefly through the redox reaction of nickel nanoparticles and Ag⁺ ions, namely galvanic reaction.