Thermal degradation of some coordination polymers

Autor: Narayan S. Bhave, Vaidyanathan N. Iyer
Rok vydání: 1987
Předmět:
Zdroj: Journal of Thermal Analysis. 32:1369-1379
ISSN: 1572-8943
0368-4466
DOI: 10.1007/bf01913337
Popis: Coordination polymers of Co(II), Ni(II) and Cu(II) were synthesized using two ligands, 5- benzylidene pseudothiohydantoin and 5-cinnamylidene pseudothiohydantoin. These polymers were characterized by dynamic and static TG, and their relative thermal stabilities were compared. The thermal stabilities found by dynamic and static TG were in harmony. The structure of the polymeric unit for each polymer was predicted with the help of thermoanalytical data. The data reveal one pattern for Co(II) and Cu(II), i.e. an (ML 2 ) n -type polymerkc unit, and another pattern for Ni(II), i.e. an (ML 2 · 2H 2 O)n-type polymeric unit. The static (isothermal) TG data were analysed by use of (i) the difference equation method, and (ii) the Avrami-Erofeyev method. The activation energies of the coordination polymers were calculated, and it was observed that the chelate polymers of Ni(II) with both ligands were more stable than those of Co(II) and Cu(II). This prediction on the basis of static TG data is in agreement with the prediction based on the activation energies and initial decomposition temperatures calculated from the dynamic TG curves.
Databáze: OpenAIRE
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