THERMAL DEGRADATION AND KINETIC PARAMETER OF TWO INSENSITIVE PROPELLANTS: AN EXPERIMENTAL STUDY
Résumé
Low vulnerability gun propellants are energetic materials designed to resist unintended ignition
stimuli. The present work aims to determine kinetic parameters for two insensitive powders. The first
propellant is made of 1,3,5-trinitro-1,3,5-triazinane, usually called hexogen (RDX), and hydroxylterminated
polybutadiene as a binder. The second one is a nitrocellulose (NC) based propellant,
which also contains diphenylamine. These propellants are commercial products and were provided
by ArianeGroup. Both propellants have a cylindrical shape with several perforations. Only a few
milligrams of each sample are used in this study. Combustion properties of these samples were already
studied and published concerning the RDX- and NC-based propellants. This experimental
study focuses on two thermal analysis methods, which are the thermogravimetric analysis (TGA)
and the differential scanning calorimetry (DSC). This study is complementary to the previous works
on combustion behavior. Data obtained with such thermal analysis techniques provide important results
concerning thermal behavior of propellants. These results are useful to study ignition and
combustion, but also storage (aging). For each propellant, DSC and TGA analyses are performed
using several heating rates to obtain their activation energies. Comparison of their reactivities is
done by working under two different gaseous atmospheres (argon and nitrogen). Activation energies
obtained using the two techniques and under the two atmospheres are given, discussed, and
compared to literature available data.