Template Synthesis of Iminodiacetic Acid Polysiloxane Immobilized Ligand Systems and their Metal Uptake Capacity
Abstract
Porous solid polysiloxane ligand systems bearing an iminodiacetic acid chelating ligand of the general formula P-IDA (where P-represents [Si-O] n polysiloxane network and IDA represent an organofunctional group) were achieved in a two-step reaction. The first step includes a template synthesis of 3-iodopropylpolysiloxane (P-I) or 3-aminopropyl-polysiloxane (P-MA) by hydrolytic polycondensation of TEOS and the corresponding silane agent in the presence of CTAB as a surfactant. The second step includes a modification of 3-iodopropylpolysiloxane with diethyliminodiac-etate or 3-aminopropylpolysiloxane with ethylchloroacetate to produce IDA-functionalized polysiloxane ligand systems P-IDA-I & P-IDA-II respectively. It was found that the modified IDA-functionalized polysiloxane ligand systems exhibited higher capacities for uptake of the metal ions (Ni 2+ , Cu 2+ and Pb 2+) than those prepared without surfactants.