Synthesis, Spectral Characterization and Biocidal Activity of Thermally Stable Polymeric Schiff Base and Its Polymer Metal Complexes

The polymer metal complexes of transition metal ions Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) with a new polymeric Schiff base containing formaldehyde and piperazine moieties have been synthesized by the condensation and characterized by elemental analyses, infrared spectra, electronic spectra, magnetic susceptibility measurements and thermogravimetric analyses (TGA). The results of the electronic spectra and magnetic moments indicate that the polymer–metal complexes of Mn(II), Co(II) and Ni(II) have octahedral geometry, while the complexes of Cu(II) and Zn(II) show square planar and tetrahedral geometry, respectively. The analyses of the thermal curves of all the polymer metal complexes show better thermal stability than the polymeric Schiff base. All compounds show excellent antibacterial as well as antifungal activity against three types of bacteria and two types of fungi. The antimicrobial activities were determined by using the agar well diffusion method with 100 μg/mL concentrations of polymer metal complex.