1-氨基-1-肼基-2,2-二硝基乙烯碱金属盐的制备及对改性双基推进剂主组分热分解的催化作用

1-氨基-1-肼基-2,2-二硝基乙烯（AHDNE）与氢氧化钾或碳酸铯反应得到相应的碱金属盐AHDNE-K 和AHDNE-Cs。 通过元素分析和红外光谱对其进行结构表征;采用单晶X射线衍射分析法测定了AHDNE-K的单晶结构,DSC技术研究了两种金属盐对3种改性双基推进剂主组分HMX、RDX和NC/NG热分解的影响。结果表明,AHDNE-K对NC/NG有明显的催化效果,使分解温度降低了约24 ℃,能量增加了1 316 J·g^-1。     

Investigation of the Decomposition Mechanism and Thermal Stability of Nitrocellulose/Nitroglycerine Based Propellants by Electron Spin Resonance

Nitrocellulose based (NC) and nitroglycerin based (NG) propellants often have a fixed acid and water content during the manufacturing time. After manufacture, the quantity and ratio of acid/water will continue to vary depending upon the conditions of storage and operation. The level of variation depends on many factors such as loading density, temperature, volume of ullage and sealing condition of the containing cartridge, just to name a few. As described in this paper and other literature, the degradation mechanisms and aging processes of NC/NG based propellants are extremely complicated. This paper describes the details of the application of Electron Spin Resonance (ESR) to study if the free‐radical mechanism is involved in the decomposition of nitrocellulose and nitroglycerin. Due to the high free‐radical intensity possessed by the propellant composition, we believe that a π complex intermediate may be formed between DPA and NG and/or NC. The formation of a π complex intermediate is not preferred because it may enhance the rate of decomposition of nitrate esters.     

Formulation and Characterization of a New Nitroglycerin‐Free Double Base Propellant

Double base propellants composed of nitrocellulose (NC) and nitroglycerine (NG) are widely used. However, the inclusion of liquid NG presents both stability and performance problems: the NG may migrate from the propellant in storage, and it softens the propellant at high inclusion levels. In this work, the novel nitrate ester 1,4‐dinitrato‐2,3‐dinitro‐2,3bis(nitratomethylene) butane (SMX) is considered as a replacement for NG in a double base propellant. Thermochemical calculations indicate improved performance when compared with the common double base propellant JA2 at SMX loadings above 40 wt‐%. Also, since SMX is a room temperature solid, migration may be mitigated. Both unplasticized and plasticized propellants were formulated to enable the study of the interaction of SMX with nitrocellulose. Thermal analysis of unplasticized propellant showed a distinct melt‐recrystallization curve, which indicates that a solid phase solution is being formed between SMX and NC, and that SMX would not act as plasticizer. Analysis of propellant prepared with diethyleneglycol dinitrate (DEGDN) plasticizer indicates that the SMX is likely dissolved in the DEGDN. The plasticized material also showed similar hardness and modulus to JA2. Safety characterization showed that sensitivity is similar to JA2. In short, replacing NG with SMX results in a new family of propellants with acceptable safety characteristics and which may also offer improved theoretical performance.     

含高氮化合物的高燃速CMDB推进剂的能量特性

利用能量计算程序计算了含高氮化合物3,6–双(1–氢–1,2,3,4–四唑–5–氨基)–1,2,4,5–四嗪(BTATz)的复合改性双基(CMDB)推进剂的能量特性,并研究了用3种含能添加剂高氯酸铵(AP)、六硝基六氮杂异伍兹烷(HNIW)、黑索今(RDX)和2种增塑剂1,5–二叠氮基–3–硝基–3–氮杂戊烷(DIANP)及二缩三乙二醇二硝酸酯(TEGDN)分别部分取代BTATz和硝化甘油(NG)后,对含BTATz的CMDB推进剂能量特性的影响规律。结果表明:无论推进剂中是否含铝粉,用BTATz取代CMDB推进剂中的硝化棉(NC)和NG后,将不同程度地降低原推进剂的各能量特性参数;用AP和HNIW部分取代BTATz后,可使BTATz–CMDB推进剂的理论比冲明显提高;用DIANP或TEGDN部分取代推进剂中的NG,各能量特性参数均随其含量增加而减小。     

A New Method for Determining the Vapor Pressure of Nitroglycerine Above Solid Rocket Propellants

Measuring the vapor pressure of compounds such as nitroglycerine (NG) which have a low volatility has not been a straightforward task in the past. There are a wide range of values in the literature for the vapor pressure of NG and furthermore, there is little information regarding the vapor pressure of this compound above solid rocket propellant formulations. We have devised a new method for determining the vapor pressure of NG both above the pure material and solids containing this nitrate ester. The values obtained for pure liquid NG are in good agreement with some previously published values. It was also found that the vapor pressure of this compound is slightly lowered when it is incorporated into solid rocket propellant formulations.     

Chemiluminescence Study on Thermal Decomposition of Nitrate Esters (PETN and NC)

Measurements of chemiluminescence (CL) during heating of nitrate esters (PETN and NC) have been conducted in the temperature range between 40 °C and 90 °C in an inert atmosphere. Faint light was emitted from the condensed-phase in steady-state fashion. This new finding implies that the thermal decomposition of nitrate esters is accompanied by some oxidation reactions. Spectral analysis of the CL showed that the light-emitting species will be the first excited triplet of carbonyl-containing products and singlet oxygen. The low-temperature CL phenomena observed for PETN and NC are represented by Arrhenius law, providing the activation energy of 63 kJ/mol (= 15 kcal/mol). Kinetic analysis of the CL has led to the result that the formation of peroxy radicals, which can be produced by oxidation of the primary products of nitrate ester bond (RO NO₂) cleavage, predominates a consecutive series of radical reactions of the CL.     

NEPE推进剂中聚氨酯的热分解行为

采用ＴＧ和ＤＳＣ两种热分析方法研究了ＮＥＰＥ推进剂中各种填料和助剂对聚醚聚氨酯粘结剂热分解行为的影响。     

静态与动态高压对含能材料热分解的影响

利用常压和高压差示扫描量热仪（DSC、PDSC）在动态和静态状下研究了CL-20、HMX、RDX、NC、NG、NG NC等几种含能材料的热分解,探讨了常压与高压条件下,静态与动态对这些含能材料热分解的影响。结果显示含能材料热分解受压力和动态气氛的影响有三种情况：1、热分解同时受到压力和动态气氛的影响;2、热分解既不受压力也不受动态气氛的影响;3、热分解只受压力的影响而不受动态气氛的影响。     

An Investigation on Thermal Decomposition of DNTF‐CMDB Propellants

The thermal decomposition of DNTF‐CMDB propellants was investigated by pressure differential scanning calorimetry (PDSC) and thermogravimetry (TG). The results show that there is only one decomposition peak on DSC curves, because the decomposition peak of DNTF cannot be separated from that of the NC/NG binder. The decomposition of DNTF can be obviously accelerated by the decomposition products of the NC/NG binder. The kinetic parameters of thermal decompositions for four DNTF‐CMDB propellants at 6 MPa were obtained by the Kissinger method. It is found that the reaction rate decreases with increasing content of DNTF.     

纳米氧化铁的制备及其对吸收药热分解催化作用的研究

用室温湿固相反应制备了纳米氧化铁，并进行了表征，用BSC研究了纳米氧化铁对吸收药（耠化棉吸收硝化甘油的混合物，NC／NG）热分解反应的催化作用，并提出了该催化反应的机理，实验结果表明，纳米氧化铁能有效地催化吸收药的热分解。     

纳米氧化镧对吸收药热分解的催化作用

研究了纳米氧化镧对吸收药(硝化棉吸收硝化甘油的混合物,NC／NG)热分解反应的催化作用,并提出了形成过渡态配合物的反应机理。实验结果表明,纳米氧化镧能有效地催化吸收药的热分解。     

2,4-二羟基苯甲酸铜纳米催化剂的合成及性能

以2,4-二羟基苯甲酸和硫酸铜制备纳米燃速催化剂，采用TEM、XRD、TG和IR等手段对催化剂样品进行表征，考察了反应终点和反应浓度对收率的影响，洗涤溶剂极性影响最终催化剂形貌，实验表明,纳米催化剂对双基推进剂NC/NG热分解有明显催化效果。     

叠氮推进剂的感度和能量特性研究

对叠氮推进剂的感度和能量特性进行了理论计算,得到了采用硝化甘油/低感度硝酸酯混合体系来降低冲击感度和摩擦感度的有效方法,以及高能量叠氮缩水甘油醚(GAP)推进剂各主要组分含量。增塑剂为硝化甘油/丁三醇三硝酸酯(NG/BTTN),增塑比为2.0,Al粉、高氯酸铵(AP)和奥克托今(HMX)质量分数分别为18%、30%和22%。     

Density functional theory and molecular dynamic investigations on the energetic and mechanical properties of nitrocellulose/nitroglycerin/pentaerythritol diazido dinitrate composites

Experimental researches stated that pentaerythritol diazido dinitrate (PDADN) may be used as an energetic plasticizer in propellants. To explore whether PDADN is an effective energetic additive of the nitrocellulose/nitroglycerin (NC/NG) double‐base propellant, in this study, various NC/NG/PDADN composites were constructed and investigated using the density functional theory and molecular dynamic methods. Results show that when the content of PDADN is less than about 20%, PDADN can increase the interactions between NC and NG and improve the mechanical properties of NC/NG; but when the content exceeds 20%, the interactions between NC and NG are weakened and the mechanical properties decrease. The composite with a mass ratio of 72.5/22.6/5.0 (NC/NG/PDADN) has the optimal mechanical properties. However, PDADN in this formula does not improve the energy output. As a whole, PDADN can be used as a plasticizer, but not an effective energetic plasticizer of NC/NG. This investigation provides a theoretical evaluation of using PDADN as an additive in the double‐base propellant and gives a practical guidance for designing the NC/NG/PDADN formula. POLYM. COMPOS., 38:192–198, 2017. © 2015 Society of Plastics Engineers     

Thermal Decomposition of Energetic Materials 83. Comparison of the Pyrolysis of Energetic Materials in Air versus Argon

T‐Jump/FTIR spectroscopy was employed to flash pyrolyze a series of energetic compounds in an air atmosphere for comparison with an argon atmosphere. The O‐NO₂ compounds (NG, NC, and PETN), N‐NO₂ compounds (RDX and HMX), and C‐NO₂ compounds (DNT, TNT, and NTO) were studied. The effect of the surrounding atmosphere on the pyrolysis gases roughly correlates with the trend in the vapor pressure of the parent energetic material (i. e. DNT>NG>TNT>NTO>PETN≈RDX>NC≈HMX). For high vapor pressure compounds, the gaseous phase reactions dominate and the dependence on the surrounding atmosphere is strong. For low vapor pressure compounds, the condensed phase decomposition dominates and the dependence on the surrounding atmosphere is weak. That is, the extent of condensed phase vs. gas phase decomposition is the major factor in the effect of the surrounding atmosphere on the decomposition gases. The main reactions in the air are CO with O₂ which is fast, and NO with O₂, which is slow. However, these pyrolysis products for the nitrate esters, the nitramines, and the C‐NO₂ compounds behave differently suggesting that a common process, such as surface catalysis, is not responsible for the behavior seen. There is little effect of the relative humidity (0–60% range) except in the case of HMX.     

改性双基推进剂主要组分的高压热分解特性

利用高压差示扫描量热仪测试了改性双基推进剂常用的ＮＣ、ＮＧ、ＲＤＸ、ＨＭＸ等几种主要组分在常压及不同压力下的热分解行为,揭示了它们的热分解行为与压力的关系,并进一步分析探讨了各组分对推进剂燃烧性能的影响。     

真空安定性判据对几种新型高能量密度化合物的适用性研究

为了研究真空安定性法对新型高能量密度化合物的适用性,采用NBK型“拉瓦”量气测试系统研究了4种新型高能量密度化合物CL-20、ADN、TNAZ、DNTF及典型一代、二代含能材料NC+NG(质量比50∶50)及RDX在恒温条件下的受热全分解过程,计算得到了其全分解放气量分别为653.53~662.38、613.80~619.82、624.04~636.23、601.52~629.82、594.52~617.25、和556.74~569.22 mL/g,真空安定性判据2 mL对应的反应深度都不超过0.4%,所对应的安全系数均大于2.5。通过对典型一代、二代含能材料及新型高能量密度化合物全分解过程的机理函数及动力学参数分析,由时温等效关系推算新型高能量密度化合物在100℃放气量达到判据2 mL的时间分别为7341~8967、2091~2808、438~664和3955~3997 h,所得结果均远大于真空安定性法规定的测试时长48 h。典型一代、二代含能材料NC+NG(质量比50∶50)及RDX在100℃受热分解放气量达到判据2 mL的时间分别为5191~6316 h和111~241 h。通过对比验证,证明几种新型高能量密度化合物可以沿用真空安定性试验2 mL判据。     

Utilization of New Non‐toxic Substances as Stabilizers for Nitrocellulose‐Based Propellants

Propellants consisting of nitrocellulose (NC) and/or other nitrate esters are inherently chemically unstable and undergo decomposition even under standard storage conditions. Decomposition of such compounds can be inhibited or nearly stopped when stabilizers are used. However, conventional stabilizers form nitrosamines that have toxic and carcinogenic effects. As a result, these conventional stabilizers should be replaced as soon as possible. A series of NC‐based propellants doped with different novel manufactured stabilizers were investigated using microcalorimetry, conventional stability tests, and sensitivity tests. The results were compared with propellants containing the conventional stabilizer Akardite II. The chemical structure of these new stabilizers and their decomposition products do not enable the formation of toxic N‐nitrosamines.     

Phase transitions and mechanical properties of nitrocellulose plasticized by glycidyl azide polymer and nitroglycerine

Films of nitrocellulose (NC), glycidyl azide polymer (GAP), and nitroglycerine (NG) have been evaluated using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, dynamic mechanical analysis (DMA), and tensile testing. The SEM micrographs demonstrate that, even at low GAP concentration, a portion of GAP will coalesce into spherical domains due to a saturation effect. This is related to the inability of higher molecular weight GAP to effectively situate itself between NC polymer chains. The addition of a small fraction of lower molecular weight NG completely changes this behavior. DMA confirms that two transitions are present and can be attributed to a plasticizer rich phase (β), a polymer rich phase (α) and that NC plasticized with GAP is in accordance with the Gordon-Taylor equation. Tensile results show that the addition of a small fraction of NG to a NC/GAP based-formulation increases elongation at break to values similar to that of the NC/NG base formulation. The combination of these two plasticizers, GAP and NG, allows for the plasticization of NC at significantly lower environmental and human toxicity levels.     

功能化石墨烯掺杂熔盐的制备及性能研究

通过物理混合方法,在由硝酸钾、硝酸钠、硝酸锂组成的熔盐中加入不同量的氧化石墨烯（GO）、钠化石墨烯（Na-GO）和钾化石墨烯（K-GO）,制得3个系列熔盐复合材料,考察功能化石墨烯的含量,氧化、钠化、钾化对熔盐复合材料熔点、热分解温度、热传导率、黏度等物化性质的影响。结果发现在添加量为0.1%~5%范围内,随着功能化石墨烯添加量的增加,熔盐复合材料的熔点先逐渐下降,后下降趋平缓,其中Na-GO对熔盐熔点下降作用最为明显;熔盐复合材料的起始分解温度随着功能化石墨烯添加量的增加而提高。GO、Na-GO和K-GO的加入提高了熔盐复合材料的热传导率,降低了其流动性能。综合考虑各种因素,在熔盐中添加0.5%~1%的Na-GO,所得熔盐复合材料的综合性能较好。