Studies on poly(Acrylate)s containing hydrazone ligand derived from 2,4- Dihydroxy carbonyl compounds and their divalent metal complexes

Abstract

2,4-dihydroxy carbonyl meth(acrylate)s hydrazones, were prepared by reacting acryloyl/methacryloyl chloride with 2,4-dihydroxy carbonyl hydrazone. 2,4-dihydroxy carbonyl hydrazone-phenol formaldehyde was prepared by condensing equimolar amount of 2,4-dihydroxy carbonyl hydrazone with formaldehyde in the presence of oxalic acid. These monomers were characterized by elemental analysis, IR and 1H-NMR spectroscopy. The monomers were polymerized in DMF medium using benzoyl peroxide as free radical initiator. The DMF solution of the polymers containing a few drops of ammonia on treatment with aqueous solution of Cu(II)/Ni(II) ions gave the corresponding metal complexes: poly(2-hydroxy- 4-acryloyloxybenzophenone hydrazone) poly(2H4ABPH)-Cu(II)/Ni(II), poly(2-hydroxy-4-methacryloyloxybenzophenone hydrazone) poly(2H4MBPH)- Cu(II)/Ni(II), poly(2-hydroxy-4 acryloyloxyacetoophenonehydrazone) poly(2H4AAPH)-Cu(II)/Ni(II), poly(2-hydroxy-4-methacryloyloxyacetoophenone) poly(2H4MAPH)-Cu(II)/Ni(II), poly(2-hydroxy-4-acryloyloxybenz aldehydehydrazone) poly(2H4ABAH)-Cu(II)/Ni(II), poly(2-hydroxy-4 methacryloyloxybenzaldehydehydrazone) poly(2H4MBAH)-Cu(II)/Ni(II) Characterization of the polymers and polymer-metal complexes were carried out. The polymers were soluble in THF, DMF, DMAc, and DMSO whereas insoluble in common organic solvents like benzene, toluene, acetone and methanol. GPC data reveals that the molecular weight W (M ) of the polymers is moderately high of the order of 3.21 × 104 - 3.94 × 104. Elemental analysis values and 1H NMR signals are in good agreement with expected structure of the polymers. The IR-spectra of polymers exhibit broad bands around 3400-3000cm-1 due to the intramolecular hydrogen bonded OH stretching,1730cm-1 due to the C=O group of ester. In the case of Cu(II) complex, the broad band is absent due to the involvement of phenolic OH group in co-ordination with the metal.