Eclética Química (Sep 2018)
Thermal degradation behaviour of some polydithiooxamide metal complexes
Abstract
The thermal decomposition behavior of the Fe(II), Co(II), Ni(II) and Zn(II) complexes of polydithiooxamide has been investigated by thermogravimetric analysis (TGA) at a heating rate of 20°C min -1 under nitrogen. The Coats-Redfern integral method is used to evaluate the kinetic param- eters for the successive steps in the decomposition sequence observed in the TGA curves. The process- es of thermal decomposition taking place in the four complexes are studied comparatively as the TGA curves indicate the difference in the thermal decomposition behavior of these complexes. The thermal stabilities of these complexes are discussed in terms of repulsion among electron pairs in the valence shell of the central ion and electronegativity effects.