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Compositions based on 2,4-dinitroanisole (DNAN) with several cyclic nitramines, namely 1,3,5-trinitro-1,3,5-triazinane (RDX) and β-1,3,5,7-tetranitro-1,3,5,7-tetrazocane (β-HMX), cis-1,3,4,6-tetranitrooctahydroimidazo-[4,5-d]imidazole (BCHMX), and ε-2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (ε-CL20) were prepared and studied in comparison with 2,4,6-trinitrotoluene (TNT) compositions. Impact and friction sensitivities, combustion heats, detonation velocities and relative explosive strengths (RS) were determined for these mixtures. Detonation parameters were calculated by means of the Explo5 thermodynamic code. The difference between the TNT and DNAN compositions was shown by the relationships between RS and the energy outputs of the prepared mixtures. The results show better sensitivity characteristics for DNAN composition in comparison with same compositions containing TNT. [ABSTRACT FROM AUTHOR]

In this work, new cyclic nitramine named cis-1,3,4,6-tetranitrooctahydroimidazo-[4,5-d]imidazole (BCHMX) was premixed with insensitive explosives (3-nitro-1,2,4-triazol-5-one, NTO and1,1-diamino-2,2-dinitroethene, FOX) and with two cyclic nitramines (1,3,5-trinitro-1,3,5-triazinane, RDXand, 1,3,5,7-tetranitro-1,3,5,7-tetrazocane, HMX) and bonded by polydimethyl-siloxane (PDMS) binder.Impact and friction sensitivities were evaluated. Detonation velocity was measured and the detonationcharacteristics were calculated by EXPLO 5 thermodynamic code. Relative explosive strength wasdetermined by using the ballistic mortar test. The results showed a great positive influence on the sensitivityof BCHMX due to the addition of the insensitive explosive (NTO, FOX-7) however the performance wasdecreased. On the other side, mixing the nitramines improved the performance with reduction of BCHMXsensitivity. PDMS binder succeed to decrease the sensitivity of all the studied mixtures.

Co-crystallization of cyclic nitramines with sterically crowded molecules, i.e., ε-2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (ε-CL-20) with cis-1,3,4,6-tetranitrooctahydroimidazo-[4,5-d]imidazole (BCHMX), is very difficult, but the co-agglomeration (slurry method) of their mixed micro-co-particles gives very good results. CL-20 is present in these co-agglomerates (CACs) in its β-form. Besides the medium of co-agglomeration, also the molar ratio is very important; it is possible to obtain β-CL-20/BCHMX (molar 1.8/1.0) with the impact sensitivity of 14.9 J. The density of these CACs approaches 99.6% of the density of the β-CL-20 crystals. Based on the application of the Raman, FTIR and PXRD techniques, it has been proved that the agglomeration of CL-20/BCHMX micro-co-particles leads to the formation of CACs mostly with the properties of co-crystals (CCs). This also seems to be confirmed by the relationships between the heat of formation and ring-deformation vibrations (in plane) and between the impact sensitivity and the difference in the asymmetric NO2 stretching vibrations in pure CL-20 and its CACs. The CACs studied have lower detonation energies than would be consistent with the percentage of individual coformers in these crystals. An examination of the most sensitive CACs (1.2 J) as a detonator primer has shown the absence of its required acceleration capabilities in the given detonator design. A comparison with literature data and our unpublished preliminary results indicates that the CACs and CCs of this type could have potential beneficial applications in propellants. [ABSTRACT FROM AUTHOR]

On 15 high nitrogen and three polynitrated polyazaarenes (including six azido-derivatives), the paper demonstrates the relations between their impact sensitivities (Edr) on the one hand and the volume heats (ρQmax) or a representative of detonation pressure (ρD2) of their explosion or their enthalpies of formation (ΔHform) on the other. The semi-logarithmic subrelations between the Edr and ρQmax values are limited by the mechanism of primary fission. While the mentioned relations between Edr and ρQmax values for azido derivatives predominantly show the expected course, in the case of the remaining high-nitrogen EMs, the opposite is the case, i.e., an increase in ρQmax values corresponds to a decrease in impact sensitivity. The same is valid for ρD2 values as an independent variable. Taking the energy content of the studied EM molecules, represented by ΔHform values, instead of the heat of explosion, yields unambiguous semilogarithmic relations, according to which the growth of the ΔHform values increases impact sensitivity. The results obtained indicate that it is necessary to distinguish between the influences of the performance and the energetic content of high-nitrogen energetic materials on their initiation reactivity. [ABSTRACT FROM AUTHOR]

A new focus in the fields of energetic materials is on preserving high performance while enhancing manipulation safety. In this work, a special type of plastic‐bonded explosive (PBX) mixture has begun to be developed by combining a new nitramine, cis‐1,3,4,6‐tetranitrooctahydroimidazo‐[4,5‐d]imidazole (BCHMX), with the thermally stable explosives 1,3‐diamino‐2,4,6‐trinitrobenzene (DATB) and 2,2',4,4',6,6'‐hexanitroazobenzene (HNAB) bonded by a styrene‐butadiene rubber (SBR) binder. The studied PBXs prepared are insensitive explosives. They have been compared with Czech plastic explosives (SEMTEX 10 and SEMTEX 1H), a new Egyptian plastic explosive (EPX‐1), a Swedish plastic explosive (Sprängdeg m/46) and with analogous PBXs, filled by 1,3,5‐trinitro‐1,3,5‐triazinane (RDX), β‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocane (β‐HMX), and cis‐1,3,4,6‐tetranitrooctahydroimidazo‐[4,5‐d]imidazole (BCHMX). The individual explosives, PETN, BCHMX, β‐HMX and RDX, have been studied as well. Thermal behavior of the pure active components has been investigated. The impact and friction sensitivities have been obtained along with the measured detonation velocities. The detonation characteristics have also been calculated using the EXPLO5 code. The relationship between performance and sensitivity to mechanical impulses has been investigated. The results have shown that DATB has a significant influence on the reduction of the sensitivity of BCHMX to a level close to TNT and much lower than all the other studied plastic explosives. In addition, the new PBX based on BCHMX and DATB has higher detonation characteristics than the commercial PBXs and TNT. The influence of DATB on BCHMX is a promising topic requiring more research for its application. [ABSTRACT FROM AUTHOR]