Abstract:1, 1-Diamino-2, 2-dinitroethylene (FOX-7) was prepared from acetamidine hydrochloride and malonate by condensation, nitration and hydrolysis. The structure of FOX-7 was characterized by IR, MS, NMR. Organic solvents was added in the nitration process, the reaction conditions were optimized as t=3 h, n_H2SO4:n_{4, 6-dihydroxy-2-methylpyrimidine}=9:1, T=10 ℃, V_{organic solvents}:V_H2SO4=1:1, the yield of FOX-7 is 89.6%.

Abstract:The main product of nitrolysis of 3, 7-dinitro-1, 3, 5.7-tetrazabicyclo[3.3.1]nonane(DPT) in dinitrogen pentoxide/nitric acid/ammonium nitrate with lower dinitrogen pentoxide concentration is HMX. While with higher dinitrogen pentoxide concentration, some of straight-chain by-products of both 1, 9-dinitroxy-2, 4, 6, 8-tetranitro-2, 4, 6, 8-tetrazanonane and N, N′-bis(hydroxymethyl)nitramide were obtained and separated by column chromatography, and the structures were confirmed with infrared spectroscopy(IR), nuclear magnetic resonance(HNMR) and mass spectrometry(MS). Increasing dinitrogen pentoxide concentration leads to more by-products. Nitrolysis of DPT in dinitrogen pentoxide/nitric acid or dinitrogen pentoxide/methylene chloride afforded only straight-chain by-products.

Abstract:1-Amino-3-methyl-1, 2, 3-triazolium nitrate(1-AMTN) was synthesized using glyoxal and hydrazine hydrate as starting materials in three steps, i.e. addition-elimination, cyclization, methylation and replacement reaction. The overall yield is 71.8%(based on glyoxal). The structure of products was confirmed by IR, MS, NMR and elemental analysis. The properties of 1-AMTN were estimated: density 1.63 g·cm^-3, enthalpy of formation 84 kJ·mol^-1 and detonation velocity 8115 m·s^-1. The key factors of cyclization and methylation were studied and the optimal reaction conditions were confirmed: medium acetonitrile, 20 ℃, and the ratio of glyoxal bishydrazone and methyl Iodide 1:5. The overall yield of cyclization and methylation is 86.7%. In addition, actived manganese oxide was recycled and its mechanism was also discussed.

Abstract:A novel Keggin heteropolyacid anionic Brϕnsted acid salt [(CH₂)₄SO₃HMim]H₂PMo₁₂O₄₀ was synthesized and used as catalyst in toluene nitration in HNO₃(67%) with good catalytic activity. With the molar ratio of toluene to nitric acid 1:3, catalyst to toluene 1:10, and reaction for 10 h at 50 ℃, the yield of mononitro products is about 84.9%, and the ratio of ortho-to para-isomers about 1.21.

Abstract:3, 3′-Bis(tetrazol-5-yl)difurazanyl ether was designed and synthesized with a yield of 46.7% from 3-amino-4-cyano furazan through oxidation, ertherification and cyclization, and was characterized by ¹³C NMR, IR, MS and elemental analysis. In addition, the mechanism of cyclization promoted by Zn²⁺ was proposed and discussed, and the reaction conditions of cyclization were optimized as follows: time is 4 h, ZnCl₂·2H₂O as catlyst, molar ratio of ZnCl₂·2H₂O to FOF-2 is 1:1.

Abstract:Methyl-4-bromo-4, 4-dinitrobutanoate was synthesized by Michael addition reaction of bromodinitromethane and methacrylate, and the effects of the ratio of raw materials, temperature and reaction time on its yield were studied. The optimum synthetic technology conditions with 54% yield are: molar ratio 2:1 of methacrylate to bromodinitromethane potassium salt, reaction temperature 40 ℃, reaction time 30 min, tetrabutyl ammonium bromide(TBAB) as phase transfer catalyst. The quantity of TBAB is equivalent to 12% of bromodinitromethane potassium salt. The structure of the product methyl-4-bromo-4, 4-dinitrobutanoate was identified by infrared spectroscopy(IR), nuclear magnetic resonance(¹H NMR), ultraviolet and visible spectroscopy(UV-Vis), mass spectroscopy(MS) and elemental analysis.

Abstract:A new energetic compound, 1-methyl-3-amino-5-nitro-1, 2, 4-triazole (DNMT), was synthesized using a new synthetic process from hydrazine dihydrochloride and methyl hydrazine as starting material via condensation, cyclization and diazo-reaction. The yield of DNMT was 62.3% and its purity was more than 99.4%. The structure of DNMT was characterized by IR, MS, NMR and elemental analysis. The condensation synthetical process were discussed in detail. The optimum reaction condition was as follow: alcohol as reaction solvent, n(C₂H₃N₄):n(NH₂NHCH₃·2HCl)=1:1.1, pH=8-9, hydrochloric acid as acidifying agent, acetone as recryctallization solvent.

Abstract:2, 4, 6, 8, 10, 12-Hexanitrohexaazaisowurtzitane(HNIW, or CL-20) exists in four crystalline polymorphs(α-, β-, γ-and ε-) which can be transited in different solvents at ambient conditions. In this work, the ε-HNIW crystallization process in a saturated HNIW solution in ethyl acetate being added to n-heptane with different addition rates. Crystal polymorph and morphology of HNIW were studied by Fourier transform infrare spectroscopy(FTIR) and scanning electron microscope(SEM), respectively. It is revealed that crystallization mechanism of ε-HNIW is kinetic-controlled when n-heptane addition rate is above 100 mL·s^-1 and the crystallization process of HNIW is that metastable phase β-HNIW nucleus firstly formed and growed; then, β→ε phase transition occured and stable phase ε-HNIW increased; at last, β-HNIW disappeared and ε-HNIW attained completely. When n-heptane addition rate is below 20 mL·s^-1, crystallization mechanism of ε-HNIW is thermodynamic-controlled and only ε-HNIW nucleus formed and growed without phase transition in the whole crystallization process. The hydrate α-HNIW will be formed if water existed in HNIW solution. So, the non-solvents used for preparation of ε-HNIW should be non-polar or poor-polar solvents, not solvents with high values of dipole moment.

Abstract:The single crystal structure of 4-amino-1, 2, 4-triazole NTO salt ((AT)(NTO)) prepared by neutral reaction of 4-amino-1, 2, 4-triazole (4-AT) and NTO was determined by a four-circel X-ray diffractometer. The results show that the crystal is moloclinic, space group P_21/c with main crystallography parameters a=7.071(2) Å, b=6.361(3) Å, c=18.792(7) Å, β=96.43(3)°, V=839.9(5) ų, Z=4, D_c=1.694 g·cm^-3, μ=0.145/mm, F(000)=440. The atoms of the 4-AT cation and the atom of the NTO anion in (AT)(NTO) crystal are in a plane of self-triazole ring. The two plane angle is 7.6°. The values of standard volume of gas evlved by 100 ℃/48 h, 50% drop height of impact sensitivity, explosion probability of friction sensitivity, 50% fire voltage and 50% fire energy by vacuum stability test(VST) and sensivity tests to impact, friction and static electricity spark are 0.28 mL·g^-1, 124.7 cm, 0%, 12.841 kV and 2.515 J, respectively, indicating that (AT)(NTO) is thermally stable and insensitive to impact, friction and spark.

Abstract:1-Methy-4, 5-dinitroimidazole(4, 5-MDNI) was prepared. The single crystal of 4, 5-MDNI was cultivated. The single crystal structure was determined by a X-ray diffractometer. The results show that the crystal is orthorhombic, space group Pna2(1)/n with crystal parameters of: a=0.8412(2) nm, b=1.2646(1) nm, c=0.6563(1) nm, V=0.6982 (3) nm³, Z=4, D_c=1.637 g·cm^-3, μ=0.15 mm^-1 and F(000)=352. The impact and friction insenstitvity of 4, 5-MDNI were tested by GJB772-1997 method. 4, 5-MDNI is insensitive to impact and friction and close to TATB.

Abstract:In order to find sensing materials used for explosives detecting, fluorescence analysis technique was used to study the fluorescence response of the fluorescence of conjugated compounds with small molecular weight and fluorescent property ethyl 2-(chloromethyl)-4-phenyl-quinoline-3-carboxylate (ECMPQC) to trace nitro-explosives in practice, and fluorescence quenching efficiency with various concentration of nitro-explosives. Electron transfer occurs when ECMPQC with nitro-explosives (such as TNT, HNS and HMX) which are lack of electrons in their molecular structures. As a result, the fluorescence intensity decreases in this system and the fluorescence intensity decreases with the concentration of TNT increasing. ECMPQC has potential application in nitro-explosives detection. The fluorescence property of ECMPQC was investigated in chloroform, acetone and ethanol. Results show that with the increase of solvent polarity, the bathochromic shift of the emission maximum wavelength becomes more remarkable. In ethanol, a new emissive band which is assigned to the formation of the exciplex is appeared in the region of 365~450 nm in fluorescence spectrum between ECMPQC and nitro-explosives.

Abstract:A series of thermoplastic polyurethane elastomers(TPUEs) with bonding function which can be used as propellant binders were synthesized from polyethylene/polypropylene adipate diol(PEPA), tetrahydrofuran/ethylene oxide copolyether(PET), isophorone diisocyanate(IPDI), 1, 4-butanediol (BDO) and diethyl bis(hydroxymethyl) malonate(DBM) as primary substances by melt pre-polymerization method. Then Fourier transform infrared spectroscopic(FTIR), gel permeation in chromatography(GPC), differential scanning calorimetry(DSC) and tensile test techniques were employed to characterize the structures and properties of TPUEs. Results show that the microphase segregation of TPUEs become more obvious with the BDO content in chain extenders increasing. When the molar content of BDO exceeds 50% in chain extender, the glass transition temperature of soft segment become lower than -70 ℃. It is also observed that tensile strength of the TPUE increased with the BDO content increasing, while the elongation to break decreased. TPUEs extended with mixed diols have better effect than that extended with BDO or DBM to improve the mechnical properties of modified double-based propellant.

Abstract:The process of laser ignition of RDX was calculated using numerical simulation. The results show that the gas phase is ignited with the accumulation of reactant and the increase of temperature and reaction rate in the gas phase after undergoing a series of processes of heating, melting, decomposing, vaporizing and flowing into gas-phase for RDX. The effect of environment pressure and laser power density on ignition delay time and critical ignition distance was discussed. The calculated ignition delay time is consistent with the results reported in previous literatures.

Abstract:According to the theory of two-dimensional steady flow and basic assumption of steady detonation, deduced compatibility relationship of characteristic curve in universal equation of state. The movement of flyer plate was investigated with characteristic curve method in sliding detonation. The flying parameters of flyer plate were compared and analysed in detonation of TNT and emulsion explosive, which were in characteristic method of polytropic equation and universal equation of state. At different mass ratios, projectile curves of flyer plate under detonation of TNT and emulsion exlosive were investigated, and compared with the calculation results. Finally, in order to verify accuracy of the calculation results, two-dimensional Richter method was used to calculate the parameters of flyer palte. Results show that the throwing angle and vertical displacement with characteristic curve of universal equation of state are less than that of Richter formula, which are greatly consistent with the distinction of Richter formula, and the maximum difference is 9%.

Abstract:The dynamic properties of two types of pressed booster explosives (JH-14C, JHB-1C) and one cast booster explosive PBXN-110 were investigated using Split Hopkinson Pressure Bars (SHPB). The macro and micro failure modes of the recovery specimen were analyzed by high-speed photography and scanning electron microscope(SEM), the corresponding stress-strain curves of three distinct explosives under high strain-rate dynamic response were obtained. Results show that the dynamic mechanical properties of pressed and cast booster explosives are distinctly different and also can be used as reference and guidance for comparison and choice of booster explosives in penetrate warhead designed for over-loading environment.

Abstract:With the help of REAL software, the energy characteristics of composite modified double-based propellant containing different ratio of CL-20, RDX and Al were calculated using least free energy method. The effect of hexanitrohexaazaisowurtzitane(CL-20), RDX and Al content changing on the energetic characteristics of the propellant was studied. The results show that with increasing the CL-20 content, the theoretical specific impulse, combustion temperature, oxygen balance and average molecular weight of combustion gas increase significantly. With adding more aluminum, the energetic parameters of the propellant increase, but Al content should be suitable to ensure the coefficient of oxygen balance higher than 0.53, otherwise energy parameters of the propellant will be reduced.

Abstract:In order to regulate the rheological properties of cast smokeless composite modified double based (CMDB) propellants composed of nitrocellulose, nitroglycerin and clotrimethylene-trinitramine, the influences of plasticizer, rheological modifier and temperature on the rheological properties of cast CMDB propellants were studied by a HAAKE rotational viscometer. The results show that CMDB propellants are pseudoplastic fluid with yield stress. By adjusting the ratio between plasticizer nitroglycerin and DINA (m(NG):m(DINA)=10:1, 8:1, 6:1), with specific plasticizer reduces, the viscosity and yield of CMDB propellants increase and the flow activation energy decreases. With the increasing in rheological modifier content, the viscosity of CMDB propellants increases obviously, and the flow activation energy decreases. The viscosity of CMDB propellants decreases at higher temperatures.

Abstract:The effects of density of grain-molded gun propellant and surface treatment of based-propellant on combustion performance of the grain-molded gun propellant were studied by closed-bomb test and 30 mm simulation ballistic gun test using high energy grain nitramine propellant RGD7A-6/7 as based-propellant. The characteristics of p-t and L-B curves for grain-molded gun propellant with different modular densities and different surface treatment of based-propellant were analyzed. The influences of density and surface treatment on the combustion property of the grain-molded gun propellant were obtained. The results show that in the density range from 1.0 g·cm^-3 to 1.5 g·cm^-3, the higher the density of the grain-molded propellant is, the better its progressivity is. The progressivity of grain-molded gun propellant MD7 obtained with surface-deterred and then surface-coated for based-propellant is the best. The muzzle velocity of MD7 at chamber pressure of 29.7 MPa increases by 6.6%. The muzzle kinetic energy increases by 13.8%.

Abstract:Four kinds of flame inhibitors with different structure and functionalities, K₂SO₄, KNO₃, new potassium salts AK and BK were selected and the powder charge samples were made using two patterns of adding flame inhibitors in desensitiged and coated course. The muzzle flames were tested with a B-shutter photography method. The effects of flame inhibitor on muzzle flame were experimentally studied. Results show that different adding patterns of the same flame inhibitors have different effect on reducing flame. The effects on reducing flame when adding in the desensitiged course are better than that in the coated course. The new potassium salts AK and BK are not hygroscropic and have better effect on reducing muzzle flame than the common flame inhibitors, K₂SO₄ and KNO₃. Under the conditions of same inhibitor and adding pattern, the more flame inhibitor adds, the better effect on muzzle flame reduces.

Abstract:A SETARAM C80 calorimeter was used in the experiment to measure the enthalpy of dissolution and thermodynamic properties of trinitrophloroglucinol (TNPG) dissolved in deionized water (H₂O) at 298.15 K. The empirical formula for the enthalpy of dissolution was calculated by polynomial expressions. The fomula is: Δ_dissH_m=106.799266-2352.19194b^1/2+15538.58581b. The standard molar enthalpy of dissolution, the relative apparent molar dissolution enthalpy and the relative partial molar enthalpy also were obtained from the experimental data of the enthalpy of dissolution of TNPG in water. The kinetic formula was obtained. From the formula the rate constant and reaction order are deduced.

Abstract:Aim at the strong hygroscopicity of ammonium dinitramid(ADN)and the necessity of the hygroscopicity investigation, a new dynamic analytical method was estabilished. The hygroscopicity of ADN was studied by a rapid analytical method. The curves describing the hygroscopic process, hygroscopic speed and critical relative humidity were obtained. Compared to airer equity method, the dynamic method showed an equivalent result to the standardization method GJB770B-2005-404.1 in accuracy. The relative standard deviation of the dynamic analytical method was 1.45%.

Abstract:The electrosynthesis of pentoxide dinitrogen from tetroxide dinitrogen with RuO₂-IrO₂ coatings on the Ti substrate as anode and IrO₂ coatings on the Ti substrate as cathode, and PTFE membrane as separator was carried out in a semi-continuous plate-and-frame electrolyzer at a constant voltage. Influences of technological parameters such as the initial concentration of tetroxide dinitrogen in anolyte solution, the flow rate of the anolyte and temperature on the electro-oxidation of tetroxide dinitrogen to form pentoxide dinitrogen were investigated. At an initial concentration of tetroxide dinitrogen in anolyte solution below 45% the current efficiency and specific energy improved with increasing the initial concentration of tetroxide dinitrogen in anolyte. At an initial concentration of tetroxide dinitrogen in anolyte solution above 45% the current efficiency tended to a constant value. However, there no significant change in the yield of pentoxide dinitrogen was found with increasing the initial concentration of tetroxide dinitrogen in anolyte solution. The higher the flow rate of the anolyte is, the higher the current efficiency and yield of pentoxide dinitrogen are and the lower the specific energy. There was an initial increase in both the current efficiency and yield of pentoxide dinitrogen with increasing temperature up to a maximum at 6 ℃, followed by a decrease in both the current efficiency and yield of pentoxide dinitrogen as temperature further increased. The tendency of the change in the specific energy was inverse with that both the current efficiency and yield of pentoxide dinitrogen. The optimized technological parameters for the electro-oxidation of tetroxide dinitrogen are initial concentration of tetroxide dinitrogen in anolyte solution of 45%, electrochemical reaction temperature of 6 ℃ and flow rate of the anolyte of 63 mL·min^-1.

Abstract:In order to evaluate the activation of aluminium powder in aluminized explosives, the activity of aluminium powder in military FLX and FLU series was measured by X-ray fluorescence (XRF) spectrometry and X-ray diffraction (XRD) spectrometry. The results show that only XRF method can be used to analyze activity of aluminium powder. A correction factor of aluminium activity is obtained by fitting results of XRF method and standardization method (chemical analysis method) GJB1738-1993. The relative deviation obtained by XRF method and chemical analysis method for detecting activity of aluminium powder in A-Ⅸ-Ⅱ explosives is less than 4%.

Abstract:D-optimal method was employed in the experiments of semiconductor bridge (SCB) ignition. The SCB with and without electrostatic discharge (ESD) were used to ignite lead styphnate (LTNR). The ignition voltage, current and time were obtained by oscillograph, and the deck ablation area of SCB was measured by microscope. It was found the ESD could do some damage on SCB, and the higher ESD, the greater deck ablation area is. Compared with the non-ESD SCB, the ignition voltage and energy of ESD SCB were lower, which means that the ESD SCB was more sensitive. The ignition energy and ignition time were measured by t-test, which showed that the ESD of 21 kV was the critical point. With higher than 21 kV, ESD had greater effect on SCB, and the lower, the less.

Abstract:An experiment device of in-line explosive trains(slapper detonator—HNS-Ⅱ—JHB-1)was designed to study the explosive performance of in-line explosive trains. The output performance of slapper detonator used in the experiment were analyzed, and the explosive performance of in-line explosive trains under low temperature and normal temperature were experimented. The results show that, in this experiment condition, slapper detonator can reliably initiate the bare insensitive JHB-1 under the condition of less 8 mm transfer intervals; slapper detonator can also reliably initiate HNS-Ⅱ under the low temperature of -40 ℃, normal temperature as well as extend transfer interval; and finally, in-line explosive trains (slapper detonator—HNS-Ⅱ—JHB-1)can reliably detonate.

Abstract:In order to study the effect of foil bridge included angle on the energy efficiency of exploding foil initiator, five exploding foil bridges of included angle as 30°, 45°, 60°, 75° and 90° were designed and fabricated by an ion etching method. Their electrical exploding performances were investigated. Results show that under the same discharge voltage, the burst current and peak current produced by foil bridge with an included angle of 45° is the largest. The analysis of the relationship between the burst current and the flyer velocity and the comparison of burst power and difference between the burst time and the peak time reveal that the exploding foil bridge with included angle of 45° has a better performance of higher energy efficiency and lower fire energy.

Abstract:A Bayesian reliability assessment method for cartridge of ejector was proposed. The reliability information of whole cartridge and its subsystems was comprehensively utilized in this method. Firstly, inheritance factor was determined, then mixed Beta distribution was established based on the reliability information of whole cartridge and its subsystems, lastly, the posterior distribution was used to assess system reliability. With new method and GJB376-1987 method and the traditional Bayesian method, the reliability of a cartridge ejector was respectively evaluated to reach 0.9922, 0.978, 0.996 under the confidence level 0.90. The result shows that the new method is effective to evaluate the reliability of cartridge of ejector.

Abstract:The failure modes of electric squib were studied during accelerated life test. The conditions of the aging test were temperature 71 ℃ and temperature 71 ℃, relative humidity 50% and 80%. The results show that the resistanc, fire time and output gass pressure did not change obviously, but the breakdown voltage dropped after accelerated life test. Especially, in the condition of humidity, the breakdown voltage of electric squib dropped significantly. By studying the effect factor to electric squib′s breakdown voltage, the reason was the inhomogeneous mixing of epoxy resin at the condition of humidity.

Abstract:Based on the special "push-pull" nitro-enmaine of the novel energetic material 1, 1-diamino-2, 2-dinitroethene(FOX-7), the reported chemical reactions of FOX-7 were summarized, including acid-base reaction, coordination reaction, nucleophilip substitution reaction of amino group, acyl reaction, oxidation reaction, reduction reaction, hydrolysis reaction, electrophilic addition reaction and azidine reaction. Reactivity of C-C double bond, amino group and nitro group of FOX-7 was analyzed, and reaction routes and mechanisms were also discussed.

Abstract:The current development of three 3,5-dinitrohydroxylpyridines (2-hydroxyl-3,5-dinitropyridine, 4-hydroxyl-3,5-dinitropyridine and 4-hydroxyl-3,5-dinitropyridine-N-oxide) derived metal and nonmetal salts concerning their syntheses, crystal structures, thermochemical properties and thermokinetic behaviors as well as their effects on combustion properties of cyclotrimethylene trinitramine-composite modified doule based(RDX-CMDB) propellants was reviewed. It was founded that all lead and copper salts derived from these 3,5-dinitrohydroxylpyridine compounds present catalytic effects on the combustion of RDX-CMDB propellants, of which the lead and copper salts of 2-hydroxyl-3,5-dinitropyridine(2HDNPPb/2HDNPCu) composite catalyst is the best one. It is predicted that some candidates with better catalytic properties as burning-rate modifiers for combustion of solid propellants will be found, when more and more novel 3,5-dinitrohydroxylpyridine derivatives and their energetic salts are synthesized and their catalytic efficiencies are evaluated.

Abstract:The synthesis of boron hydrides were briefly reviewed, and latest study as solid propellant burning rate catalyst were summarized. Ionic borohydride salt and carborane can respectively regulate solid propellant burning rate in large ranges, but the synthesis process of ionic borohydride salt is relatively simple and low cost. With high density, high energy, insensitive and low toxicity, energetic ionic liquids (salt) has good prospects in propellants and explosives.

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