Effect of the nature of crosslinking agents on the thermal decomposition of metal complexes of crosslinked polyacrylamide-supported dithiocarbamates

Abstract

The thermal decomposition of metal complexes of dithiocarbamate functions supported on crosslinked polyacrylamides in different structural environments was investigated. The dithiocarbamate functions were incorporated into the polyacrylamide supports by a two-step polymer-analogous reaction. The phenomenological and kinetic parameters of the thermal decomposition of the metal complexes were observed to vary with the nature of the crosslinking agent in the polymer support. The thermal stabilities of the metal complexes are higher than the stability of the free dithiocarbamate resin. In the Cu(II) and Ni(II) complexes of N,N'-methylenebisacrylamide-crosslinked polyacrylamide-supported dithiocarbamates the Ni(II) complexes have the higher thermal stability. In the Cu(II) and Ni(II) complexes, the activation energy decreases with increasing crosslinking, reaches a minimum, then increases and again decreases. The energy values fit into the general equation for a cubic polynomial. The entropies of the metal complexes are more positive than the entropy of the uncomplexed resin.