High-Temperature Decomposition of Ammonium Perchlorate-Polystyr ene-Catalyst Mixtures

Abstract

The study was performed on the kinetics and mechanism of chemical reactions in the ammonium perchlorate (AP)-polystyrene (PS)-Fe2O3 mixtures. The experiment simulated the processes of thermal decomposition and combustion, as well as the catalysis of these processes. By means of an elaborate technique using a time-of-flight mass-spectrometer, a study was made of the influence of AP particle size (4-300//), the ratio of AP and PS, temperature (305-390°C), pressure (15 mm Hg, 1 atm.) and concentration of the catalyst Fe2O3 (2.5%-12.5%) on kinetic parameters of the decomposition of rich and stoichiometric (8 :1) AP and PS mixtures. It was concluded from analyses of the kinetic data that the thermal decomposition of these systems is a multistage process. Such stages are reactions of perchloric acid (primary product of the AP dissociation) with PS and condensed products of this interaction. The validity of this follows from direct experiments on the reaction kinetics of HC1O4-PS. It has been shown that in the decomposition of mixtures with AP (250-400/i), HC1O4 diffusion from the AP surface through a polymer film, and its simultaneous reaction with the latter are limiting stages. The developed model of the thermal decomposition of the AP-PS-catalyst system is based on the data obtained.