Elastomeric micro- and ultrafine-rubber are first considered as binders in melt-cast explosives for improving the mechanical properties. Acrylonitrile-butadiene rubber (NBR), in ultrafine fully vulcanized form (UF-NBR), carboxylated acrylonitrile-butadiene rubber (CNBR), in ultrafine fully vulcanized form (UF-CNBR), styrene-butadiene rubber (SBR), in ultrafine fully vulcanized form (UF-SBR), carboxylated styrene-butadiene rubber (CSBR), in ultrafine fully vulcanized form (UF-CSBR), acrylic rubber (ACM), in ultrafine fully vulcanized form (UF-ACM), room temperature vulcanized silicone rubber (RTV), in ultrafine fully vulcanized form (UF-RTV) and polytetrafluoroethene (PTFE) in micro-rubber form (PTFE-M) were utilized for modifying 2,4,6-trinitrotoluene (TNT) based melt-cast explosives. Based on their dispersity in TNT and RDX slurry, only UF-NBR, UF-CNBR and PTFE-M can be used. In the modification experiment, their influence on the mechanical and detonation performance of the matrixes were studied, as well as the impact sensitivity. Compared with PTFE-M and UF-CNBR, UF-NBR improved the tensile and compressive strength of the original formulation CYCLOTOL-65/35. The toughening mechanism was also explained through interfacial interactions and fracture energy analysis. The predicted detonation properties of the modified formulations (detonation pressure variations from 26 to 28 GPa, detonation velocity variations from 7900 to 8100 m/s) are at the same energy level as CYCLOTOL-65/35. In addition, the drop hammer impact testing results confirm that the formulation containing UF-NBR is more sensitive than the one with UF-CNBR, with the same amount of additive.
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Thermal reactivities of 1,3,5-trinitroso-1,3,5-triazinane (TmTa), 1,3,5-trinitro-1,3,5-triazinane (RDX), 2,4,6-trinitrotoluene (TNT), TNT/TmTa and RDX/TmTa mixtures and mixtures of 1,3,5-trinitrobenzene (TNB) with TmTa and TMTA/RDX were specified by means of differential thermal analysis with outputs evaluation by the Kissinger method. The reactivities, expressed as Ea R-1 slopes of Kissinger relationship, correlate with squares of detonation velocities of the corresponding explosive samples in the sense of modified Evans-Polanyi-Semenov equation. Taking this fact it is stated that initiation of detonation of the mixtures with TMTA content proceeds through primarily fission of the TMTA molecule. If an ionic mechanism dominantly participates on thermal decomposition of some studied mixtures then resulting Ea R-1values do not correlate in the sense of the equation. This is the case of the TNT/TmTa mixtures where TNT has acidic character toward TmTa. also in TNB/TmTa/RDX mixture might react amine intermediates of TmTa thermal decomposition with RDX by ionic mechanism.
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The paper deals with possible applications of the connection of liquid chromatography with atmospheric pressure chemical ionization (APCI) mass spectrometry (Agilent 1100 series LS-MSD system) and gas chromatography with electron capture detector (GC-ECD) in the analysis of some common available or improvised explosives. The analysis of selected types of individual explosives, 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitroso-1,3,5-triazinane (TMTA) and analysis of their mixtures (TNT/TMTA and RDX/TMTA) in their post-explosion residues on the basis of generated characteristic mass spectra by using LC-MSD system is the aim of this work. Post-explosion analysis of TMTA and its explosive mixtures can be similarly complicated, like that of the well-known plastic explosive on the basis of pentaerythritol tetranitrate, Semtex-1A.
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