Poly(acrylic acid-co-maleic acid)-metal complexes with copper(II), cobalt(II), and nickel(II) -: Synthesis, characterization and structure of its metal chelates

Polychelates were obtained by addition of an aqueous solution of the copolymer poly(acrylic acid-co-maleic acid) to the aqueous solutions of Cu(II), Co(II), and Ni(II) chlorides. Elemental analyses, as well as magnetic, spectral and thermal properties, in addition to electrical conductivities of the chelates were investigated, and possible structures have been assigned to the chelates. All the polychelates were found to include water. The chelate with Co(II) showed a thermotropic effect between 50 degrees C and 70 degrees C with a change in color, thermal behavior, and geometry arrangement. Semi-empirical calculations at the PM3 level were carried out on the geometrical arrangement of the polychelates. (C) 1999 Elsevier Science Ltd. All rights reserved.