Thermal Studies of Organozinc films: part XI

Cárdenas T. Galo; Oliva C. Ricardo; H. Luis D. Tagle

Abstract

The thermal stability of organozinc films was studied by thermogravimetric analysis (TGA) between 25 and 550°C mint-1. The decomposition temperatures were obtained from the maximum of the first derivatives of the TG curve. The kinetic parameters of the thermal decomposition were determined by the Arrhenius equation. All the films degraded in one step with a very small weight loss. Films prepared with toluene and THF exhibit higher weight losses, 23.77% and 12.48%, respectively, and zinc-2-propanol film is the most stable (1.11% weight loss). The variation in thermal stability is discussed in relation to the various solvents used and comparisons are made with the results reported for Pd, Ge and In organo films. For organozinc films, the stability decreases for the solvents used in the order: dimethyl sulphoxide (DMSO), isobutyl methyl ketone, 2-butanone, ethanol, 2-propanol, acetone, dimethylformamide (DMF), tetrahydrofuran (THF). The activation energies of the thermal degradation are comparable with those for organo-Pd films. The order of reaction for the thermal decomposition of organozinc films was found to be −0.5 for most of them, with films prepared from ethanol and toluene having zero reaction order. The pre-exponential factor, the reaction order and the activation energy of the decomposition for organozinc films have been determined for most of the solvents.

Más información

Título de la Revista: THERMOCHIMICA ACTA
Volumen: 232
Número: 2
Editorial: Elsevier
Fecha de publicación: 1994
Página de inicio: 279
Página final: 284
Notas: DOI:10.1016/0040-6031(94)80068-5