L. Pedroso

New Propellant Component, Part II. Study of a PSAN/DNAM/HTPB Based Formulation

A study of DNAM as a candidate ingredient for propellant formulations is reported. A formulation including DNAM and based on Phase Stabilized Ammonium Nitrate (PSAN) and Hydroxy-Terminated-Poly Butadiene (HTPB) was selected for the study. This includes thermoanalytical measurements on the mixtures of solid components and propellant samples. Performance is assessed by burning rate measurements. A new small-scale shock sensitivity test developed for studying the propellant under consideration is described. A good potential for DNAM was found for this formulation as revealed by the performance and low vulnerability of the PSAN/DNAM/HTPB composition.

Thermal decomposition of solid mixtures of 2-oxy-4,6-dinitramine-s-triazine (DNAM) and phase stabilized ammonium nitrate (PSAN)

Abstract The thermal decomposition of solid mixtures of 2-oxy-4,6-dinitramine- s -triazine (DNAM) and phase stabilized ammonium nitrate (PSAN) at different mass ratios has been studied. Simultaneous thermal analysis (DSC/TG) and thermomicroscopy have been used. It was found that PSAN promotes the lowering of the decomposition temperature of DNAM. The beginning of this process occurs when both components are in the solid state irrespective of the composition. However, the composition appears as the main factor determining the process progression once initiated. These observations are interpreted in the light of known properties of both DNAM and PSAN. Non-isothermal kinetic analysis, restricted to the early stage of the decomposition process, has been performed for the particular DNAM/PSAN ratios of 50/50 and 60/40. The complexity of the process is evidenced by the impossibility of being described by a kinetic model function other than an empirical one (Sestak–Berggren). Noticeable differences in the apparent Arrhenius parameters were found, indicating remarkable changes in the process over the composition range of the kinetic analysis.

New Propellant Component, Part I. Study of 4,6-Dinitroamino-1,3,5-Triazine-2(1 H)-One (DNAM)

This paper reports a study of the synthesis and characterization of 4,6-dinitroamino-1,3,5-triazine-2(1 H)-one (DNAM) carried out under the perspective of looking for new ingredients in propellant formulations. Emphasis is given to the characterization of DNAM. The following attributes were identified: low sensitivity to impact and friction, thermal stability over a wide temperature range, energetic nature, high density, and interesting particle size distribution. In Part 2 a preliminary evaluation of DNAM capabilities in a propellant formulation will be presented.

Low-Temperature FTIR Spectroscopic and Theoretical Study on an Energetic Nitroimine: Dinitroammeline (DNAM)

This paper presents an overview of recent progress in spectroscopic studies of the energetic nitroimine 4,6-bis(nitroimino)-1,3,5-triazinan-2-one (DNAM), based on experimental and theoretical data. The following topics are considered: variable temperature FTIR spectroscopy (4000-400 cm(-1)) applied to the study of natural and isotopically substituted (deuterated) samples aiming to obtain a successful vibrational assignment of the spectra and to investigate H-bonding interactions; extensive theoretical work based on accurate quantum chemical calculations (ab initio MP2 and DFT/B3LYP; harmonic and anharmonic vibrational calculations) to model and help interpreting the experimental findings, as well as to provide fundamental data on this simple prototype nitroimine that can be used as a starting point to the study of more complex related compounds. This work allowed us to reveal detailed features of the IR spectrum of the title compound, presenting, for the first time, plausible assignments.

Detonation Meso‐Scale Tests for Energetic Materials

The objective of the present study is to characterize, on the meso‐scale level, the detonation behaviour of PBX based on HMX , based in the minimisation of the test samples of energetic materials up to 10 mg. The development of a non‐intrusive, high resolution, optical metrology procedures, using multi‐fibber strip, allows the testing of PBX micro‐samples, formed by few crystals surrounded by binder, with the simultaneous registration of parameters as local detonation velocity and pressure, geometrical shape of detonation front and the structure of the shock‐to‐detonation transition zone. The enhanced information allows a better understanding of the processes of formation and propagation of detonation wave. This procedure can be applied to the study of new advanced energetic materials.

Synergetic phenomena in detonation of solid heterogeneous explosives. Control of oscillations and dissipative structures in detonation flow

We present experimental evidences for existence of synergetic effects in detonations of PBX -most advanced class of the modern high explosives. Both phenomena, oscillating regimes of detonation propagation and origination of dissipative structures in detonation flow are detected at wide variation of global geometry of detonation flow and PBX macro-structure.

DMTA Analysis of Propellants Based on Inert and Energetic Binder Systems

Abstract. In this work, we compare the mechanical properties of a widely used inert binder based on HTPB and a new energetic binder based on GAP and DNAM as additive, by DMTA technique. Both formulations are tested on their own and filled with ammonium perchlorate, a current high performance filler. The DMTA results show a wide operational temperature range for the inert binder systems along with a high resistance to propellant cracking, when compared with the energetic binder systems.