Thermal Aspects of Coordination Polymeric Chain Assemblies of Some Transition Metal Ions with 8-Hydroxy Quinoline

Abstract

The novel chelating (QMCM) has been synthesized through copolymerization of 8-hydroxyquinoline and 4,4′-methylene bisphenol monomers in the presence of a base as a catalyst. The novel developed copolymer ligand (H2L) has been used to prepare a series of five polymeric chelates (ML) using transition metal ions. The chemical structure of polychelates on the basis of elemental and IR characterization suggests that the uninegative bidentate ligand (H2L) coordinates to metal ions through an oxygen atom of the phenolic hydroxyl group by replacing the hydrogen atom and nitrogen of the quinoline ring. The studies of magnetic moments and electronic spectra reveal that all polychelates with octahedral geometry are paramagnetic in nature, except that of Zn(II) chelate, which is diamagnetic. The thermogravimetric analysis of parent ligand and its metal chelates have shown remarkable difference in mode of thermal decomposition and their thermal stabilities. The kinetic parameter and energy of activation (E a) of thermal decomposition has also been estimated by the Broido method.