Polymer complexes - XXXIII. Potentiometric and thermodynamic studies of 2-acrylamido-1-phenyl-2-aminothiourea and its metal complexes in monomeric and polymeric forms

Abstract

The proton-monomeric ligand dissociation and metal-monomeric ligand stability constants of 2-acrylamido-1-phenyl-2-aminothiourea (APAT) with some transition metal ions were calculated potentiometrically in 0.1 M KCl and a 50% (v/v) ethanol-water mixture. The proton-polymeric ligand dissociation and metal-polymeric ligand stability constants in the presence of 2,2′-azobisisobutyronitrile as initiatior were also calculated. The effect of temperature on the dissociation of APAT and the stability of its formed complexes were studied in monomeric and polymeric forms. The corresponding thermodynamic functions were derived and discussed. The dissociation process is non-spontaneous, endothermic, and entropically unfavourable. The formation of the metal complexes is spontaneous, endothermic, and entropically favourable.