Metal ion complexation of hydrophilic polymeric amino ligands derived from tetraethyleneglycol diacrylate (TTEGDA)-crosslinked polyacrylamides

Abstract

Complexation behaviour of amino ligands supported on polyacrylamides with 2–20 mol% of tetraethyleneglycol diacrylate crosslinks was investigated towards Co(II), Ni(II), Cu(II), Zn(II) and Hg(II) ions. The metal ion intake was dependent on the extent of crosslinking and followed the order: Hg(II) > Cu(II) > Zn(II) > Ni(II) > Co(II). The aminopolyacrylamides and their metal complexes were characterised by IR and EPR techniques. The absorptions of the ligands were shifted by complexation with metal ions and the EPR spectrum suggested distorted tetragonal geometry for the Cu(II) complex. The thermogravimetric analysis of the metal complexes revealed a pattern of variation of thermal stability on incorporation of metal ions. The kinetics and adsorption parameters of complexation, swelling characteristics, recyclability and specificity of metal-desorbed systems are also described.