HMX在γ-丁内酯中结晶介稳特性研究

采用激光检测观察法测量了奥克托今(HMX)在γ-丁内酯中的溶解度。运用最小二乘法根据Apelblat经验方程建立溶解度与温度的关系式。研究了饱和温度、搅拌速率及降温速率对介稳区宽度的影响。根据经典成核理论,计算了受搅拌速率、降温速率影响的成核级数。结果表明,在HMX的结晶过程中,介稳区宽度随饱和温度和降温速率的升高而明显变宽,随搅拌速率的增加逐渐变窄。受降温速率和搅拌速率影响的成核级数均与饱和温度有关。成核级数随饱和温度的升高逐渐变小。HMX在γ-丁内酯中适宜的冷却结晶条件为饱和温度40℃,降温速率0.1~0.2℃·min~(-1),搅拌速率400 r·min~(-1)。     

喷雾干燥法制备球形HMX的正交实验

以丙酮为溶剂,采用L_9(3~4)正交实验优化了喷雾干燥制备球形HMX的工艺条件。利用扫描电镜(SEM)对优化条件下所得的球形HMX进行了表征。采用评分法定量分析了其形貌。结果表明,球形HMX的最优制备条件为:入口温度70℃,进料速率1.5 mL·min~(-1),喷雾气体流速473 L·h~(-1),质量分数1.5%。最优制备工艺条件下所得HMX颗粒的中值粒径为997.56 nm,晶型为β型。与HMX原料相比,球形HMX的撞击感度的特性落高提高28.21 cm。     

Study of Plastic Explosives based on Attractive Cyclic Nitramines Part I. Detonation Characteristics of Explosives with PIB Binder

Four plastic explosives based on energetic nitramines and a non‐energetic binder were prepared and studied. The nitramines were RDX (1,3,5‐trinitro‐1,3,5‐triazine), HMX (1,3,5,7‐tetranitro‐1,3,5,7‐tetrazine), BCHMX (cis‐1,3,4,6‐tetranitro‐octahydroimidazo‐[4,5‐d]imidazole) and HNIW (ε‐2,4,6,8,10,12‐hexanitro‐2,4,6,8,10,12‐hexaazaisowurtzitane, ε‐CL‐20). The binder was in all cases polyisobutylene (PIB) as in the standard composition C‐4. These powerful plastic explosives were compared to standard PETN‐based commercially available explosives Semtex 1A and Sprängdeg m/46. The detonation velocities were experimentally measured and compared to the ones calculated by the Kamlet–Jacobs method, CHEETAH and EXPLO5 Codes. The experimental detonation velocities as well as the calculated detonation parameters decrease in the following order: HNIW‐PIB>HMX‐PIB≥BCHMX‐PIB>RDX‐PIB>Sprändeg m/46≥Semtex 1A. Urizar coefficients for the various binders were calculated from experimental data.     

热红联用研究AP与RDX和HMX混合体系的热分解

用DSC—TG—FTIR（热红）联用研究了RDX／AP，HMx／AP，RDx／HMx和RDX／HMX／AP混合体系的热分解，测定和比较了它们的热分析特征量和分解气相产物。结果表明，AP与RDX和HMX之间存在强烈的相互作用，尤其是与后者的作用更强烈。在AP（不含碳）分解的温度区间，混合体系的分解也出现CO、CO2和CH2O等碳氧化物，说明体系中RDX和HMX分解的部分产物或残渣与AP同时分解。     

Neutral Polymeric Bonding Agents (NPBA) and Their Use in Smokeless Composite Rocket Propellants Based on HMX‐GAP‐BuNENA

Very few efficient bonding agents for use in solid rocket propellants with nitramine filler materials and energetic binder systems are currently available. In this work, we report the synthesis, detailed characterization, and use of neutral polymeric bonding agents (NPBA) in isocyanate‐cured and smokeless composite rocket propellants based on the nitramine octogen (HMX), the energetic binder glycidyl azide polymer (GAP), and the energetic plasticizer N‐butyl‐2‐nitratoethylnitramine (BuNENA). These polymeric bonding agents clearly influenced the viscosity of the uncured propellant mixtures and provided significantly enhanced mechanical properties to the cured propellants, even at low NPBA concentrations (down to 0.001 wt‐% of propellant). A modified NPBA more or less free of hydroxyl functionalities for interactions with isocyanate curing agent provided the same level of mechanical improvement as regular NPBA containing a substantial number of reactive hydroxyl groups. However, some degree of reactivity towards isocyanate is essential for function.     

DNTF/TNT/HMX基熔铸炸药流变性能研究

为了得到流变性能良好并且适用于微型沟槽装药的熔铸炸药配方,选取质量比为60/40的DNTF/TNT作为熔铸载体,HMX作为固相主体炸药,制备了不同配比时的熔铸炸药,并采用Brookfield R/S Plus流变仪对其进行了流变性能测试.对比和分析了固相主体炸药HMX的百分含量、颗粒大小和形貌以及温度对熔铸炸药粘度的影响.结果表明:随着HMX含量的增大和粒径的减小,熔铸悬浮体系的粘度增大;随着温度的升高,熔铸悬浮体系的粘度减小;在温度为85~90℃,适当的搅拌条件下,2μm超细主体炸药HMX的含量在40%~50%时,该熔铸配方具有良好的微型沟槽装药工艺性能.     

Study of Thermal Reactivity and Kinetics of HMX and Its PBX by Different Methods

Vacuum Stability Test (VST) was used to determine the thermal behavior and kinetic parameters of 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and its mixture with hydroxyl-terminated polybutadiene (HTPB) as a binder coded as HMX/HTPB.Model fitting and isoconversional method were applied to determine the kinetic parameters based on VST results.For comparison,non-isothermal thermogravimetry analysis data (TGA) was also used to calculate the kinetic parameters by using Kissinger,OFW (Ozawa,Flynn,and Wall) and KAS (Kissinger-Akahira-Sunose) methods.Advanced Kinetics and Technology Solution (AKTS) software was also used to determine the decomposition kinetics of the studied samples.Differential Scanning Calorimetry (DSC) was employed to determine the decomposition heat flow properties of the studied samples.Results show that the activation energies obtained using VST results is 360.1kJ/ mol for pure HMX and 186.9kJ /mol for HMX/HTPB.The activation energies obtained by the three different methods using TGA results are in the range of 360-368kJ/mol for pure HMX and 190-206kJ/mol for HMX/HTPB.It is concluded that values of kinetic parameters obtained by VST are close to that obtained by the different techniques using TG/DTG results.The onset decomposition peak of HMX/HTPB is lower than that of HMX where the HTPB binder has negative effect on the thermal stability of HMX.The results of all the applied techniques prove that HMX/HTPB has lower activation energy and heat release than the pure HMX.HTPB polymeric matrix has negative effect on the kinetic parameters of HMX.     

水悬浮包覆造粒下含能黏结剂在PBX 炸药中的应用

为获得更高能量的压装混合炸药,采用含能黏结剂在水悬浮造粒方法下包覆HMX 制备PBX 炸药,对制 备出PBX 炸药的能量与机械感度性能进行研究。结果表明,同等配比情况下,使用含能黏结剂比使用惰性黏结剂制 备的PBX 炸药能量明显提高。与以聚氨酯热塑性弹性体(Estane)制备的LX-14Ⅱ相比,以GAP 基ETPE 制备的JO-13 爆速增加109 m/s、爆热增加226 kJ/kg(提高4.2%);以BAMO/AMMO 基ETPE 制备的JO-X 爆速增加182 m/s、爆 热增加318 kJ/kg(提高5.9%),在能量提高的同时,机械感度有所增大。     

Laser‐Induced Deflagration of Unconfined HMX – The Effect of Energetic Binders

The effect of three energetic binders [poly(3‐methyl‐3‐nitratomethyloxetane (polyNIMMO), polyglycidyl nitrate (polyGLYN) and an energetic polyphosphazene (PPZ‐E) – all at 10%] on the unconfined laser‐induced deflagration of cyclotetramethylene tetranitramine, commonly known as High Melting point Explosive (HMX) by a near IR (NIR) diode laser (801 nm) has been examined. Hydroxyl terminated polybutadiene (HTPB) and PPZ (the precursor to PPZ‐E – before nitration) were used as reference materials. The formulations required the addition of an optical sensitizer – carbon black (CB) – for ignition. At the designated threshold flux density of 2.3 kW cm⁻², a minimum of ∼1 wt.‐% CB was needed for the reliable ignition of unbound HMX and its formulations with polyGLYN, PPZ‐E and PPZ. Under similar conditions HMX/polyNIMMO and HMX/HTPB required 3% CB. Ignition maps (ignition time versus laser flux density) have been constructed for the five formulations. Comparison of ignition times and ignition energy densities for HMX and HMX/polyGLYN showed this binder to have only a marginal effect. In contrast, HTPB, PPZ and PPZ‐E all retarded HMX ignition at the threshold flux density, but showed negligible effect at higher flux densities. As PPZ and PPZ‐E produced both similar delays in the ignition time and similar increases in the flame development times (10–90%) at the threshold flux density, the inhibition of the HMX ignition by these PPZs appears to be largely independent of the polymer energy content. Such characteristics could be useful for high performance and insensitive energetic formulations. PolyNIMMO (3% CB) increased the ignition time of HMX only slightly at 2.3 kW cm⁻². However, at this threshold flux level the HMX flame development times with polyNIMMO or HTPB were much longer than that for the unbound material; this effect is attributed to the enhanced CB content.     

HMX/TATB基高聚物粘结传爆药的研究

为解决传爆药品种少,安全性不能满足现代战争要求的矛盾,运用混合粘结技术和主体炸药的粒度级配技术,采用正交试验确定了新传爆药的配方奥克托今(HMX)细43.25%,粗43.25%,三硝基均苯三胺(TATB)10%,氟橡胶(VitonA)2.5%,聚硝基苯撑(PNP)1.0%。用溶液-水悬浮法制备了该传爆药的造型粉,测试了该造型粉的主要性能,结果表明,该传爆药不仅具备了PBXN-5传爆药流散性和成型性好的特点,而且能量、体积膨胀率、耐热性、安全性明显改善。