Synthesis and Polymerization of Copper(II) and Cobalt(III) Complexes Containing 3-(2-Pyrrolylmethylenimino)propene-1 or p-(2-Pyrrolylmethylenimino)styrene

Abstract

The Cu(II)or Co(III)-Complexes of the two Schiff-base ligands, 3-(2-pyrrolylmethylenimino) propene-1(PIP) and p-(2-pyrrolylmethylenimino)styrene(PIS), were synthesized. The radical polymerizability of the vinyl groups in these comple, xes was studied.
The kinetic order with respect to the initiator was O.5 in the copolymerization of Cu(PIP)2 with AN and was 1.0 in the homopolymerization of Cu(PIS)2. These results suggested that the termination mechanisms changed with the difference of the conjugated system in the complexed monomers. Since transition metal ions acted as a kind of retarder, the polymerization rate was low and the molecular weight of the polymer c6mplexes obtained' was small. The inhibition effect of metal ions or complexes depended on their redex-potentials and electronic structures of d-orbital, so that the inhibition effect of Co(II)-complexes was greater than that of Co(III)-or Cu(I)-complex.
Large ri-values were obtained in both the copolymerization systems, i.e., Co(PIP)s (Mi)-AN (M2) and Cu(PIS)2 (Mi)-St (M2) systems. This may be due to the unchanged vinyl groups coordinated to the metal ions in the polymer.
On the polymerization of Cu(PIS)2 complex, the intramoleeular electron transfer mechanism was assumed and the formation of uncross-linked polymer could be explained in terms of this mechanism.