Kinetic study of the thermal degradation of porous ammonium perchlorate-based composite solid rocket propellant

摘要

Composite propellants are highly particle loaded elastomers used in solid rocket motor technology. These energetic materials are made by the incorporation of the oxidizing load and fuel in an organic matrix. During the past 60 years, the thermal decomposition of ammonium perchlorate has been the subject of various research works. Among these research activities, partial decomposition of ammonium perchlorate at low temperature has been observed. This property enables us to produce porous ammonium perchlorate and to use it as an ingredient in composite propellant charge. The aim of this work is to study the effect of porous ammonium perchlorate on thermal properties.and ballistic properties of rocket composite propellant. The first phase of this study consists in the preparation of porous ammonium perchlorate (oxidizer), from commercial ammonium perchlorate using a Pyrex cell. Samples of propellant grains were prepared by casting molded using the porous and non porous ammonium perchlorate and polyvinyl chloride as a binder. No combustion catalysts have been added in order to keep the investigation focused on the influence of the porosities on the thermal properties. The second part of this study is the morphological characterization of the produced porous ammonium perchlorate using scanning electronic microscopy (SEM), and the characterization of propellant systems by DSC for thermal kinetics evaluation using different kinetic models. Experimental results indicate that the thermal properties of composite propellants containing porous ammonium perchlorate are better than the composite propellants containing normal ammonium perchlorate.