模型复合推进剂燃烧转爆轰研究

本文较详细地研究了模型推进剂(AP/wax,AP/A1/wax,AP/RDX/A1/wax)由燃烧转爆轰(DDT)的过程。分析了装药密度和铝粉含量对装药DDT的影响。结果表明:模型推进剂当其配比接近零氧平衡时较易产生DDT;含与不含铝粉的AP/粘合剂系复合推进剂药柱以及硝胺含量为20％的AP/硝胺炸药/A1粘合剂系复合推进剂药柱都不可能产生DDT。     

Distortions in nitramine substituted cubanes: The structures of N,N′-dinitro-1,4-diaminocubane,N,N′-dinitro-N,N′-(2-pyridyl)-1,4-diaminocubane,and 1,2,4,7-tetrakis(N-methoxycarbonylnitramino)cubane

The structures of three nitramine substituted cubane molecules, N,N-dinitro-1,4-diaminocubane (1), N,N-dinitro-N,N-(2-pyridyl)-1,4-diaminocubane (2), and 1,2,4,7-Tetrakis(N-methoxycarbonylnitramino)-cubane (3), have been determined.1 crystallized in the space group P2₁/a with cell dimensionsa=6.545(1),b=9.331(1),c=7.459(1) Å, =105.80(1),2 crystallized in the monoclinic space group P2₁/a with cell dimensionsa=7.545(2),b=8.697(3),c=12.406(4 Å, =96.28(3)°, while3 crystallized in the monoclinic space group P2₁/c with cell dimensionsa=10.866(3),b=6.866(2),c=16.167(6) Å, =108.79(3)°. The metrical parameters of the cubane skeleton showed no significant deviations from those found in other similarly substituted cubane molecules. For2 and3 there were considerable distortions of the nitramine moiety from planarity in contrast to1 where the nitramine moiety was almost exactly planar. The bond distances and angles for the nitramine group in1 indicates a substantial introduction of double bond character into the N–N bond in1, achieved by delocalization of the amine lone pair, compared with2 and3.     

Electrooxidation of primary nitramine anions on platinum in MeCN

Oxidation of primary nitramine anions RNNO₂ ⁻Bu₄N⁺ (R=Me, Et, Pr¹, or methoxyfurazanyl) in 0.1N Bu₄NClO₄ in MeCN on a Pt anode was studied by voltammetry and controlled potential electrolysis. It was found that the first stage of oxidation affords the corresponding radicals, which are further stabilized due to hydrogen abstraction from the medium. These radicals are also involved in other reactions, including those, which yield azo derivatives. The possibility of generation of nitrene species in these reactions is discussed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1935–1939, October, 1999.     

环杂硝胺结构和性能的DFT比较研究

用密度泛函理论（DFT）B3LYP方法,在6－31G^**基组水平下,全优化计算了 环二甲撑二硝胺（DAX）、环三甲撑三硝胺（RDX）、环四甲撑四硝胺（HMX）和环 五甲撑五硝胺（CRX）共4种环杂硝胺同系物的分子几何构型、电子结构、IR谱和热 力学性质,揭示了它们结构和性质的异同。基于Kamlet公式计算了这4种化合物的 爆速和爆压,求得与已有实验相符的递变规律。     

Substituent effect on the molecular stability, group interaction, detonation performance, and thermolysis mechanism of nitroamino-substituted cyclopentanes and cyclohexanes

Density functional theory (DFT) method has been employed to study the effect of nitroamino group as a substituent in cyclopentane and cyclohexane, which usually construct the polycyclic or caged nitra-mines. Molecular structures were investigated at the B3LYP/6-31G** level, and isodesmic reactions were designed for calculating the group interactions. The results show that the group interactions ac-cord with the group additivity, increasing with the increasing number of nitroamino groups. The dis-tance between substituents influences the interactions. Detonation performances were evaluated by the Kamlet-Jacobs equations based on the predicted densities and heats of formation, while thermal stability and pyrolysis mechanism were studied by the computations of bond dissociation energy (BDE). It is found that the contributions of nitroamino groups to the detonation heat, detonation velocity, detonation pressure, and stability all deviate from the group additivity. Only 3a, 3b, and 9a-9c may be novel potential candidates of high energy density materials (HEDMs) according to the quantitative cri-teria of HEDM (ρ≈ 1.9 g/cm3, D ≈ 9.0 km/s, P ≈ 40.0 GPa). Stability decreases with the increasing number of N-NO2 groups, and homolysis of N-NO2 bond is the initial step in the thermolysis of the title com-pounds. Coupled with the demand of thermal stability (BDE > 20 kcal/mol), only 1,2,4-trinitrotriazacy-clohexane and 1,2,4,5-tetranitrotetraazacyclohexane are suggested as feasible energetic materials. These results may provide basic information for the molecular design of HEDMs.     

Density functional theory studies of effects of boron replacement on the structure and property of RDX and HMX

In this study, based on two model nitramine compounds hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5, 7-tetrazocine (HMX), two series of new energetic molecules were designed by replacing carbon atoms in the ring with different amounts of boron atoms, their structures and performances were investigated theoretically by the density functional theory method. The results showed that the boron replacement could affect the molecular shape and electronic structure of RDX and HMX greatly, and then would do harm to the main performance like the heat of formation, density, and sensitivity. However, the compound RDX-B2 is an exception; it was formed by replacing two boron atoms into the system of RDX and has the symmetric boat-like structure. Its oxygen balance (4.9%), density (1.91 g/cm³), detonation velocity (8.85 km/s), and detonation pressure (36.9 GPa) are all higher than RDX. Furthermore, RDX-B2 has shorter and stronger N NO₂ bonds than RDX, making it possesses lower sensitivity (45 cm) and better thermal stability (the bond dissociation energy for the N NO₂ bond is 204.7 kJ/mol) than RDX. Besides, RDX-B1 and HMX-B4 also have good overall performance; these three new molecules may be regarded as a new potential candidate for high energy density compounds.     

丁硝胺乙基硝酸酯合成2-叠氮乙基丁硝胺反应动力学研究

丁硝胺乙基硝酸酯（BuNENA）叠氮化是合成2-叠氮乙基丁硝胺（BuAENA）的经典方法.利用高效液相色谱法跟踪反应过程中原料浓度随时间的变化情况,对该反应动力学进行了研究.通过对实验数据的拟合,得出了62,70和80℃下的反应速率常数.结果表明反应为二级反应,分反应级数各为一级,反应的表观活化能Ea为85.06 kJ...     

Promising Oxygen- and Nitrogen-Rich Azidonitramino Ether Plasticizers for Energetic Materials

A simple, mild and general method has been developed for the preparation of alkyl nitramines bearing a halogenoalkoxylic moiety. From these reactive halogen intermediates, a few azidoalkoxyl alkyl nitramines have been produced as energetic plasticizers. This simple protocol allows azidonitramino ether plasticizers to be obtained from available precursors in high yields, as it is safe and viable for large-scale operations. The resulting products have been fully characterized by spectral methods, and their impact sensitivity, thermal transformations and burning properties were determined, thus allowing complete comparison to the analogues including other combinations of structural units. Such characterization of these new plasticizers illustrates the extent to which the nature and position of the functional units can be used to tune the above properties of these nitramines. All azidonitramino ethers are liquid with excellent energetic performance and are promising candidates for new environmentally friendly energetic materials.     

Electrosynthesis of diazene oxides under oxidation of nitramine anions at Pt in MeCN in the presence of nitrosobenzene

The electrooxidation of anions of primary nitramine salts RNNO ₂ ⁻ M⁺ (R=Me, Et, methoxyfurazanyl; M⁺=Bu₄N⁺, Li⁺, Na⁺) at a Pt anode in the presence of nitrosobenzene in divided and undivided cells was studied by potentio-and amperostatic electrolysis. Solutions of alkali metals and tetrabutylammonium salt in anhydrous MeCN were used as supporting electrolytes. Electrolysis can result in the formation of the corresponding diazene oxide, whose yield depends on the nature of the cation of the supporting electrolyte. In an undivided cell, the yield of diazene oxide increases owing to the regeneration of nitramine anions due to cathodic deprotonation of the nonionized form. The latter is formed by the stabilization of some radical intermediates by the elimination of hydrogen atoms from the components of the medium. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1427–1431, August, 2000.     

Theoretical studies on high energetic density nitramine explosives containing pyridine

The insensitive property of explosives containing pyridine is combined with the high energy of nitramine explosives,and the concept of new nitramine explosives containing pyridine is proposed,into which nitramine group with N N bonds is introduced as much as possible.Based on molecular structures of nitramine compounds containing pyridine,density functional theory(DFT) calculation method was applied to study designed molecules at B3LYP/6-31+G(d) level.The geometric and electronic structures,density,heats of formation(HOF),detonation performance and bond dissociation energies(BDE) were investigated and comparable to 1,3,5-trinitro-1,3,5-triazinane(RDX) and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX).The simulation results reveal that molecules B and D perform similarly to traditionally used RDX.Molecule E outperform RDX,with performance that approach that of HMX and may be considered as potential candidate of high energy density compound(HEDC).These results provide basic information for molecular design of novel high energetic density compounds.