Spectroscopic study of the effect of a new metal chelate on the stability of PVC

Abstract

This work deals with the preparation of a new tetradentate ligand [ H2L] of the N2O2 type, N{2[3(1-carboxyiminoethyl)-1-phenyl]butilydene-2-amino propionic acid}, and its metal complexes with Cr(III), Fe(III), Cu(II) and Zn(II) and fully characterized by H1 NMR, C13 NMR, FTIR, UV–Vis, CHN elemental analysis, magnetic moment and molar conductance in DMF solutions. Based on the experimental results obtained, octahedral geometries of Cr(III) and Fe(III) have been suggested, while Cu(II) and Zn(II) had square planar and tetrahedral symmetries, respectively. The effect of this new metal complex on the photo degradation of poly(vinyl chloride) PVC films blended with a concentration range of 2–2.5% by weight of this new complex was investigated. The changes in the average molecular weight of PVC with irradiation time were tracked to determine the order of activities of each metal complex toward the photodegradation of PVC, andthe photodegradation of PVC films was determined by measuring carbonyl, hydroxyl and polyene indices. The results showed that Cr(III) and Fe(III) complexes increase the rate of C–C cleavage and behave as UV photo degradation substances, while the Zn(II) complex behaves as a UV stabilizer.