In order to study the thermal hazard of n-butylethanolamine in nitration reactions, a Calvet microcalorimetry was used to measure the exothermic evolution of the two-step nitration reactions, differential scanning calorimetry (DSC) was used to measure the thermal decomposition curves of the initial materials and nitration products at different stages of the two-step nitration reaction, and the most unstable reaction system during the reaction process was determined by comparing the initial decomposition temperature. Adiabatic acceleration calorimetry was used to measure the heat release process of the most unstable materials under adiabatic conditions, and the thermal safety characteristic parameters were obtained based on the adiabatic decomposition kinetics model. Finally, the degree of danger of BuEA nitration reaction was determined by the principles of reaction risk assessment. This study provides critical safety technical guidance for the BuEA synthesis process and safety design. The result shows that the BuEA nitration reaction is a strong exothermicity reaction. The maximum temperature of a synthesis reaction (MTSR) is 234.12 °C. The initial stage of the first-step nitration reaction represents the most unstable reaction system, and TD24 is 57.31 °C. According to the relationship among the TP, MTSR, TD24 and MTT, the degree of danger of the reaction can be divided into five levels. It is indicated that the adding rate of BuEA should be strictly controlled during the reaction process to keep the temperature rise below 57.31 °C and prevent decomposition exotherm in the reaction system. This study is the first systematic thermal hazard assessment for BuEA nitration process, filling the research blank of thermal safety for BuNENA industrial production. It provides essential technical support for defining safe operating boundaries, optimizing feeding control, and realizing inherent safety in synthesis and engineering design.

The thermal decomposition mechanism of 2,4,6-triamino-1,3,5-triazine-1,3-dioxide (MDO) was investigateded using a combined approach of differential scanning calorimetry- thermogravimetric-mass spectrometry-fourier transform infrared (DSC-TG-MS-FTIR) techniques and ReaxFF molecular dynamics (ReaxFF MD) simulations. ReaxFF was employed to conduct ReaxFF MD of the response process of MDO under thermal stimulation, and the intermediate and final products of MDO thermal decomposition were obtained at temperatures of 2500 K, 3000 K, 3500 K, and 4000 K. The simulations results indicate that the initial decomposition stage of MDO predominantly involves H transfer and cleavage of N-H and N-O bonds. Subsequently, the intermediates undergo a series of complex interactions to form the final products, with the primary gaseous products of N2, H2, NH3, and CO2. The gaseous pyrolysis products derived from ReaxFF MD simulations were validated and analyzed by DSCTG-MS-FTIR techniques, which enhanced the reliability of the simulation data. By integrating experimental and simulation results, the microscopic process of MDO thermal decomposition was elucidated, leading to the identification of the primary decomposition pathways. This study contributes to the safe application of MDO as an energetic material.

3,4-Dinitrofurazanfuroxan (DNTF) exhibited pronounced detonation properties and moderate sensitivity, but restricted on thermal decomposition investigation in melt-cast explosives owing to the volatility. Thereby, we employed pressurized experimental methods and density functional theory (DFT) simulation to comprehensively study the thermal decomposition mechanisms of DNTF, DNTF/CL-20 and DNTF/TKX-50 mixtures. The decomposition peak temperatures of DNTF/CL-20 and DNTF/TKX-50 systems shifted forward by 62 °C and 51 °C compared with DNTF, along with multi-step composite autocatalytic reactions. Through pressurized DSC/TG-FTIR-MS characterization and DFT calculations, the initial decomposition was triggered by (O)NO bond rupture on furoxan ring, NNO2 bond cleavage in liquefied CL-20 for DNTF/CL-20 mixture, and (O)NO bond dissociation of DNTF rings activated by NH3OH+ from TKX-50, respectively, originating from intermolecular π-π and O−H•••π interactions. We provided a feasible strategy combining experiments and DFT simulations to elucidate thermal decomposition mechanism of DNTF-based materials, holing great potential for optimizing DNTF-based melt-cast explosive formulations.

In order to study the thermal hazard of butyl nitrooxyethyl nitramine (BuNENA), differential scanning calorimetry (DSC) was used to measure the thermal decomposition curves at heating rates of 2.5 °C·min−1, 5 °C·min−1, 10 °C·min−1 and 20 °C·min−1. A thermal decomposition kinetic model was established by fitting DSC curves and the thermal hazards of BuNENA was assessed, which can effectively support the intrinsic safety design of BuNENA production and transportation processes, the establishment of scientific early warning systems, and the formulation of safety precautionary measures. The result indicates that BuNENA begins to thermal decomposition at 158.2–195.7 °C. As the heating rates increase, both the initial decomposition temperature (T0) and the peak temperature (Tp) moved toward the high temperature. The Freidman method indicate that the thermal decomposition of BuNENA is a complex process, the activation energy (Ea) and pre-exponential (ln A) are 90–190 kJ·mol−1 and 17–37 s−1, respectively. The kinetic model has been established comprising continuous reactions which contain three steps, and kinetic parameters of each step are obtained. Additionally, the curve of time to maximum (TMRad) illustrate the process temperature should not be higher than 95.17 °C during the preparation and use of BuNENA, and the ambient temperature should be maintained below 74 °C during transportation.

Organoaluminum compounds have been employed as catalysts in many reactions. However, due to their high reactivity of the Al-C bond towards water or air, the accurate analysis and detection of organoaluminum compounds are still challenging. Here we demonstrate the possibility of rapidly and precisely detecting the purity and impurities of triethylaluminium (TEAL). An indirect GC-MS method via alcoholysis reaction using a designed alcoholysis reactor was adopted to detect and separate the main components and impurities of the synthesized TEAL. Previously, the nuclear magnetic resonance (NMR) and the inductively coupled plasma-mass spectrometer (ICP-MS) methods were also selected to detect the main compounds in the synthesized TEAL. The impurities in TEAL was identified as n-butyl aluminum, and the purity of synthesized TEAL is 97.47 % with high accuracy (ca. 99 %). This work suggests a new strategy to detect the purity and impurities of some kind of hazardous compounds.

目的 探索实际贮存状态NEPE推进剂自重产生的诱发压力对其贮存寿命的影响,开展温度-压力双应力作用下NEPE推进剂的寿命预估研究.方法 对比分析NEPE推进剂在加速老化试验过程中的失效机理,确定其老化失效模式以及老化失效参量,采用加速老化试验及力学性能测试,分析NEPE推进剂加速老化过程中力学性能的变化规律.基于不同温度-压力应力条件下NEPE推进剂老化特性的变化规律,构建温度-压力双应力作用的贮存寿命预估模型,对25℃和2 MPa下NEPE推进剂的寿命进行评估.结果 温度、预紧压力升高均会促进NEPE推进剂力学性能的衰减.结论 相比于单温度应力下的加速老化特性,温度-压力双应力作用会提高NEPE推进剂试片力学性能的衰减速度,考虑推进剂的自重影响因素,采用温度-压力双应力条件下的NEPE推进剂寿命预估模型,可以更准确地预测NEPE推进剂的贮存寿命.

目的 针对3,4-二硝基呋咱基氧化呋咱(DNTF)使用和贮存过程的安全性问题,拟开展老化过程的安全性研究,获得老化过程热稳定性、机械感度等变化规律及机理,为DNTF的安全使用和贮存提供技术指导.方法 通过高温加速老化试验,分别研究DNTF在老化过程中的热稳定性、机械感度等安全性能变化,利用显微拉曼光谱技术和液相色谱-质谱联用技术对安全性能变化进行机理分析,并且开展不同温度下的加速老化试验,利用贝瑟洛特方程对DNTF的寿命进行预估.结果 DNTF经过90℃和115 d老化后,热失重特征温度由195.1℃升高至199.0～202.0℃,摩擦感度由60％升高至96％,撞击感度由52％升高至84％;拉曼光谱半峰宽由6.3709 cm?1变为6.1103 cm?1.液相色谱-质谱联用分析结果表明,质量损失1％的DNTF老化样品中有DNTF二聚体和四聚体的生成;以质量损失1％为寿命终点,预估25℃下含能材料DNTF的寿命为673.5 a.结论 高温加速老化有助于提高DNTF的热稳定性,但是会导致机械感度升高,推测是DNTF老化过程晶体品质提升和DNTF二聚体、四聚体等杂质生成的原因.

Safety evaluation of chemical reactions is very significant before industrial applications are conducted. A lot of thermal hazards are generated in the synthesis of 3,4-bis(4-nitrofurazan-3-yl)furoxan (DNTF) because of the strong exothermicity of the oxidation reaction, unstable hydrogen peroxide, and interactions between the materials. In this article, systematic parameters regarding the safe synthesis of DNTF were studied, including the preparation stage of reaction solution and the oxidation reaction step. A Calvet microcalorimeter and an RC1mx reaction calorimeter were employed for process safety research. Differential scanning calorimetry and adiabatic accelerating rate calorimetry were used to investigate the thermal stabilities of the materials and their thermal hazards. After screening of the thermal stabilities of the materials in the two stages, hazardous materials were identified, and their thermal safety parameters were obtained. Finally, two evaluation methods were applied to evaluate the hazard levels of the preparation process and the oxidation reaction process in the synthesis of DNTF on the basis of thermal safety parameters. This study provides critical safety technical guidance for the DNTF synthesis process and safety design.

（C6H14N2）［Na（ClO4）3］ is a representative of energetic perovskite compounds. It is necessary to clarify the corresponding thermal decomposition behavior， thermal decomposition mechanism and sensitivity characteristics in order to promote the application in formulations and to solve the current lack of thermal and sensitivity studies on （C6H14N2）［Na（ClO4）3］. Thermal decomposition parameters， including heat release amount and decomposition temperatures， were obtained by simultaneous differential scanning calorimetric and thermogravimetric analyses （DSC‑TG） methods. The relevant decomposition mechanism was analyzed by kinetic simulation calculations. The decomposition products and decomposition processes of （C6H14N2）［Na（ClO4）3］ were explored by DSC/TG‑FTIR‑MS coupled technique combined with in‑situ infrared technology. The parameters of thermal sensitivity， friction sensitivity and impact sensitivity were obtained by national military standard methods. The results show that the heat of decomposition of （C6H14N2）［Na（ClO4）3］ is 4227 J·g-1 at the heating rate of 10 ℃·min-1 and the decomposition temperature reaches 345 ℃， which is higher than that of most active energetic materials， including Hexogen （RDX）， ogen （HMX） and hexanitrohexaazoisowuzane （CL‑20）， indicating an outstanding thermal stability. The decomposition products analysis shows that the cubic cage‑like skeleton effectively stabilizes the internal organic molecule， resulting in the high thermal stability of （C6H14N2）［Na（ClO4）3］. In addition， the outgassing amount of （C6H14N2）［Na（ClO4）3］ heated at 100 ℃ for 48 h is about 0.04 mL·g-1， and the impact sensitivity and mechanical sensitivity are 32% and 80%， respectively， which are better than RDX and HMX.

The dissolution behavior of N-butyl zaideethylnitramin(BuAENA)dissolved in DMSO(dimethyl sulfoxide)has been studied in the paper,and a method that can predict the dissolution enthalpy was also established.The dissolution properties of BuAENA in DMSO at four different temperatures under atmospheric pressure were measured by using a C80 microcalorimeter.The results show that the dissolution process for the BuAENA in DMSO is endothermic,and the empirical formulate of dissolu-tion enthalpies at 298.15,303.15,308.15 and 313.15 K are ΔdissH=60.17b-23.02b1'2+5.09,Δdiss H=62.17b-23.58b1/2+5.24,ΔdissH=65.45b-24.01 b1/2+5.37 and ΔdissH=68.57b-24.91 b1/2+5.60,respectively.The em-pirical formulate of the dissolution enthalpy of BuAENA dissolved in DMSO can be described as Δdiss H=(-53 080.91)/T+237.81 b+11 329.26/T-60.96b1/2+(-3 128.95)/T+15.57.And the accuracy is verified by measuring the dissolution enthalpy of the BuAENA in DMSO at 343.15K.The values of activation energy E and pre-exponential factor A for the dissolu-tion process are 3.35kJ/mol and 10-2.05s-1,respectively.

为探索新的特征参量来预估NEPE推进剂的贮存寿命,采用高温加速老化方法,通过老化样品性能测试,检测老化过程中爆热、力学性能、燃速、有效安定剂含量、热爆炸临界温度、交联密度等参量的变化,并利用Bethelot方程评估NEPE推进剂的贮存寿命.结果表明,NEPE推进剂在高温加速老化过程中爆热、燃速、热爆炸临界温度及有效安定剂含量随老化时间未出现显著变化,最大抗拉强度、交联密度随老化时间显著降低且具有规律性,表明力学性能、交联密度的下降是推进剂的主要失效模式,即力学性能和交联密度可作为特征参量;以交联密度性能下降至85％作为失效终点,评估NEPE推进剂在30℃下的贮存寿命为18.5 a,两种不同特征参量对NEPE推进剂贮存寿命的评估结果基本一致,可为NEPE推进剂贮存寿命研究提供指导.

The detection and separation of impurities are crucial for the quality control of triethylboron. While the purity of triethylboron is the key factor for ballistic performance, impact accuracy, and storage safety. This work will explore a modified gas chromatography-mass spectrometer method to detect and separate the impurities in synthesized triethylboron. They are identified as CH3CH2OCH2CH3, (CH3CH2)(3)B, (CH3CH2O)(3)B, CH3CH2CH2CH2B(CH3CH2)(2) and (CH3CH2)(3)O3B3. Further, optimized GC conditions are demonstrated to quantify the synthesized triethylboron accurately and determine its purity. The purity of triethylboron is 96.39 % via a normalization method with high accuracy (RSD=0.05 %). The optimized GC conditions were as follows: a hydrogen flame ionization detector, nitrogen as carrier gas whose pathway was installed with a water trap and an oxygen trap, an HP-5 capillary column (30 mx0.32 mmx0.25 mu m) with the column temperature of 60 degrees C, an inlet temperature of 120 degrees C, the detector temperature of 150 degrees C, and an injection volume of 0.6 mu L. This work demonstrates a simple and precise method to analyze the synthesized triethylboron and its impurities.

In the synthesis process of N-nitrodihydroxyethyl dinitrate (DINA) with the HNO3-Mg(NO3)(2) method, the thermal stability of the nitration reaction liquid of the final state is poor, which leads to the thermal runaway of the entire reaction system easily. The research on the thermal runaway reaction under actual reaction conditions indicates high consumption and high risk. In this article, thermal decomposition behavior and isothermal thermal decomposition kinetics of the nitration reaction liquid of the final state in the synthesis process of DINA were investigated by differential scanning calorimetry (DSC) and microcalorimetry. The mechanism of the stability of the nitration reaction liquid was explored. The thermal safety of the material in a large-scale reactor was simulated and predicted by a thermal simulation software on the basis of kinetic parameters including activation energy, pre-exponential factors, and mechanistic functions. These findings not only avoid the risk and consumption of large-size materials but also guide their application in process optimization, inherent safety design, and handling.

为研究丁基叠氮乙基硝胺(BuAENA)叠氮化反应过程中物料的热危险性,以反应过程中所涉及的原料、6种反应中间物料和产物为研究对象,对其热稳定性展开研究.采用差示扫描量热法(DSC)获得了物料的热分解曲线,筛选出最不稳定的物料.采用绝热加速量热法(ARC)研究了最不稳定物料在绝热条件下的热分解历程,建立了绝热动力学模型,并获得TD24等热安全性参数.结果表明,刚加入NaN3时刻的反应液物料(1#样品)最不稳定,在绝热条件下的分解绝热温升为404.34℃,分解热为867.13 J/g,按照失控反应严重度评估准则判定其发生失控分解的后果是严重的;1#样品的绝热分解活化能Ea=150.55 kJ/mol,指前因子lnk0=29.44 s-1,反应级数n=0.16,基于动力学模型得到绝热条件下24 h达到最大反应速率的温度TD24=132.14℃.因此,在BuAENA叠氮化反应过程中,反应温度应控制在132.14℃以下,以确保反应的安全性.

In order to obtain the critical temperatures of energetic materials thermal reaction in different scales, a multi-scale thermal reaction test system has been developed. In this experiment, the measurement method of thermal diffusivity of energetic materials under test conditions is added. Based on the measured thermal diffusivity in thermal reaction test, activation energy and pre exponential factor measured in laboratory. The critical temperatures of thermal reaction in different scales of DINA are calculated, the calculation results are verified by two different scale thermal reaction tests, and the test results are in good agreement with the calculation results. According to the above calculation method, the critical temperature of thermal reaction of DINA under actual process conditions is obtained; it provides the basis of safety data for enterprise safety production.

In the thermal analysis of many energetic compounds, there is a phenomenon of melting before decomposition, and the melting endothermic process is masked by the subsequent rapid exothermic decomposition, which has affected the research of separation in melting and thermal decomposition processes. 2-oximemalononitrile, an energetic intermediate whose melting and decomposition processes had the overlapping, was used as the research object in this paper, and the complete melting and decomposition processes were acquired by MATLAB software, separately. In addition, the kinetics and mechanism of thermal decomposition of 2-oximemalononitrile were investigated by Málek method, which was used as guidance for the safe application in handling, processing, and storage.

采用差示扫描量热实验分别研究了丁基硝氧乙基硝胺(BuNENA)和硝化甘油(NG)的热分解特性,获得热分解动力学参数,同时建立一种温度危险等级的确定方法.以改性双基推进剂浇铸工艺为例,得到了BuNENA和NG在改性双基推进剂浇铸工艺的温度危险等级.结果表明,BuNENA和NG的热分解动力学参数分别为(1)BuNENA:Ea=124.15 kJ/mol,lnA=25.92 s-1;(2)NG:Ea=108.01 kJ/mol,lnA=22.16 s-1.BuNENA的热稳定性优于NG;BuNENA和NG在改性双基推进剂浇铸工艺的温度危险等级分别为3级和8级.因此,BuNENA作为增塑剂能够显著降低改性双基推进剂浇铸工艺的温度危险性.

为提高螺压改性双基推进剂压延工艺的安全性,研究了水分含量与改性双基推进剂压延物料热稳定性的相关性.利用烘箱法测得了压延过程中推进剂物料的含水量;利用热爆炸实验研究了不同含水量压延物料的热爆炸特征,获得了热爆炸延滞期随含水量的变化曲线;采用热重实验研究了含水量为30％(质量分数)的压延物料在70℃下的热失重变化,得到了失重过程中干燥速率随含水量的变化曲线,并根据Arrhenius公式计算得到其动力学参数.结果表明,第二、四、六遍压延物料的含水量分别为28.05％ 、27.17％ 、26.40％;随着含水量的增大,物料发生热爆炸的延滞期越长,由于水分与物料的结合方式不同,热爆炸延滞期随水分含量的变化曲线呈三段式规律变化.其中当含水量为10％ ～30％ 时,热爆炸延滞期随含水量的变化并不明显,因此含水量在10％ ～30％ 范围内的压延物料可进行多次压延以降低含水量,并提高推进剂的性能;通过Arrhenius公式计算得到该物料的活化能为31.68 kJ/mol,指前因子为1.23 s-1.

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556.74～569.22mL/g,真空安定性判据2mL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2mL的时间分别为7341～8967、2091～2808、438～664和3955～3997h,所得结果均远大于真空安定性法规定的测试时长48h.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2mL的时间分别为5191～6316h和111～241h.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2mL判据.