Regularities of thermolysis for the Fe(II), Co(II), and Ni(II) salts of maleic and ortho-phthalic acids with the formation of metal/polymer composites

Regularities of the thermolysis of acidic salts of unsaturated (maleic) [M(H₂O)₄(C₄H₃O₄)₂] and aromatic (ortho-phthalic) [M(H₂O)₆](C₈H₅O₄)₂ (M = Fe(II), Co(II), and Ni(II)) acids are established. The thermolysis of both maleates and phthalates can conventionally be divided into three stages. The onset decomposition temperature of the maleates is insignificantly higher than that of the phthalates for the salts of similar metals. The onset dehydration temperature increases in the series of the acidic transition metal maleates and phthalates Fe < Co < Ni, whereas the decarboxylation temperature decreases in the series Fe > Co > Ni. Composites consisting of a metal, an organic polymer, and amorphous carbon are the thermolysis products of both maleates and phthalates in a helium flow. The composites with iron and cobalt in the polymer contain nanosized metal particles and oxide nanoparticles, whose content increases in the composites obtained by the decomposition of phthalates, whereas only metal nanoparticles are observed in the composite with nickel. The compositions and structures of the carbon/polymer matrix differ in these composites.