RDX和HMX晶体压制方程的对比研究

分别选取经过不同重结晶工艺处理的RDX和HMX晶体和一种工业级原料颗粒样品进行准静态压制实验，由实验应力／位移曲线获得压制曲线，采用Kawakita和Heckel方程对压制曲线进行拟合。结果表明，拟合所得的常数具有模量倒数量纲，能区分重结晶和原料样品，用作含能晶体品质评价的定量参数。比较两个压制方程的模拟情况，对RDX颗粒两个方程均拟合得很好，而对HMX颗粒存在一定的误差，尤其是Heckel方程误差较大。选取压制过程的形变破碎阶段的数据所得结果其区分度有明显提高，同时两个方程的拟合情况均得到明显改善。对于含能材料颗粒，Kawakita方程更合适。     

钢模压制下高品质HMX晶体的损伤规律

为了揭示粒度分布与压制期内含能晶体损伤程度的关系,研究了3种不同粒径的高品质HMX炸药在压制后微结构和粒度分布的变化。结果表明,随着HMX晶体粒径的增大,晶体表面逐渐形成裂纹,其尖端和棱角发生破碎。当晶体尺寸达到222.5μm时会出现明显的穿晶断裂。采用两种粒度的HMX级配,可减少对晶体中的损伤。压缩刚度法所得HMX的黏结强度和光电子能谱所得PBX造型粉的包复度表明,随着颗粒粒径的增大,炸药的包覆效果和力学强度降低,导致压制PBX中更多晶体的破碎。     

RDX和HMX单晶的压痕断裂韧性

使用纳米压痕仪在HMX、RDX单晶表面进行压痕实验,并用不同压痕方程计算了单晶的断裂韧性.计算得到HMX晶体(010)面与RDX晶体(020)、(210)面间断裂韧性分别力0.092543、0.097387、0.10072 MPa·m1/2.结果表明,实验单晶的KIC值遵循Palmqvist系裂纹系统shetty方程,...     

RDX和HMX的热分解I.热分析特征量

用PDSC和TG-DTG研究了RDX和HMX的热分解,探讨了各种试验条件,包括试样量、升温速率和动静态高压等的影响。在分解过程中相态变化引起反应的加速是HMX的分解较RDX剧烈的主要原因,HMX的自加热和自催化也因此变得较RDX更显著。     

β-环糊精与RDX,HMX的包合研究

通过测定溶液的紫外吸收光谱,得到了β-环糊精(β-CD)与RDX,HMX的最佳包合比为1∶1;采用饱和溶液法对β-环糊精与含能材料RDX,HMX进行包合,得到了β-环糊精与RDX、HMX的固体包合产物;通过测定固体产品的X-射线衍射,证明了包合物的形成。     

HMX熔点与所含杂质RDX含量的估测

为了确定影响HMX熔点的因素, 采用毛细管数字熔点仪和差示扫描量热仪进行了纯品RDX和HMX试样的熔点实验.通过在丙酮中重结晶的方式,制备了含有RDX的HMX试样,并不断增大RDX含量,测试了该系列重结晶试样的熔点.结果表明,影响熔点的主要因素是试样中的有机杂质含量和重结晶情况.RDX在HMX中的质量分数为0～25%和94%～100%时,有机杂质含量与相应的熔点呈线性关系,说明根据熔点可大致判断HMX中杂质RDX的含量.     

RDX和HMX的热分解III.分解机理

简述RDX和HM X热分解的各种机理,其热分解的初始过程是N-N和C-N键断裂的竞争反应,试验条件和样品相态等因素影响竞争过程。用DSC-FT IR联用技术和热裂解原位池/FT IR分析了主要分解气相产物和凝聚相中主要官能团的变化。结果表明,RDX和HM X热分解的主要分解气相产物为N2O,CH2O,CO,CO2,H2O和HCN。RDX的分解气相产物CH2O和H2O红外吸收率的温度关系曲线都产生双峰,RDX基团-NNO2的吸收带1 589 cm-1和1 278 cm-1有两个不同速率的变化过程。用N-N键和C-N键竞争断裂的观点解释了RDX与HM X热分析和产物分析的结果。     

RDX和HMX的热分解Ⅲ.分解机理

简述RDX和HMX热分解的各种机理,其热分解的初始过程是N—N和C—N键断裂的竞争反应,试验条件和样品相态等因素影响竞争过程。用DSC—FTIR联用技术和热裂解原位池／FTIR分析了主要分解气相产物和凝聚相中主要官能团的变化。结果表明,RDX和HMX热分解的主要分解气相产物为N2O,CH2O,CO,CO2,H2O和HCN。RDX的分解气相产物CH2O和H2O红外吸收率的温度关系曲线都产生双峰,RDX基团-NNO2的吸收带1589cm^-1和1278cm^-1有两个不同速率的变化过程。用N—N键和C—N键竞争断裂的观点解释了RDX与HMX热分析和产物分析的结果。     

用微量热法研究RDX和HMX的稀释/结晶动力学

导出了描述结晶生长过程的3个热动力学方程和这些动力学方程的参数与常数间的2个关系式。用Calvet微热量计测定了RDX和HMX从二甲基亚砜、环已酮和硝酸中的稀释／结晶总放热量和产热速率。用导出的方程和关系式处理了RDX和HMX的放热稀释／结晶生长过程的动力学数据。结果表明,RDX和HMX的放热稀释／结晶过程服从Burton—Cabrera—Frank位错理论。     

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。     

超细HMX和RDX撞击感度的研究

利用爆炸概率法对超细奥克托今（ＨＭＸ）和黑索今（ＲＤＸ）的撞击感度进行了研究。试验结果表明：超细ＨＭＸ和ＲＤＸ的爆炸分数相比军用标准样品的值有较大幅度下降。文章分析了撞击感度降低的原因,并展望了超细炸药在高能量、低感度炸药研制中的重要意义。     

RDX and HMX with Reduced Sensitivity Towards Shock Initiation–RS‐RDX and RS‐HMX

Reduced Sensitivity RDX (RS‐RDX) has received a lot of attention and interest from the explosive community in the recent years. There are several producers of RS‐RDX, most of them using a direct nitration (Woolwich process) for the RDX synthesis, while Chemring Nobel uses the Bachmann process. The processes for obtaining the RS properties probably differ between the various producers. Chemring Nobel has also developed an HMX quality that shows Reduced Sensitivity (RS‐HMX) of different particle size distributions. The shock sensitivity is at the same level as for RS‐RDX in comparable compositions. Reduced shock sensitivity has been obtained for RS‐RDX and Reduced Sensitivity (RS‐HMX) in both pressable and cast‐cured compositions. By using a pressable composition, it is possible to get the results from a BICT gap test faster than from a cast‐cured composition that has to go through a curing process. Chemring Nobel in cooperation with FFI have performed an extensive accelerated ageing testing of RS‐RDX produced by the Bachmann process. The samples have been aged at 60 and 70 °C and the shock sensitivity tested by two different gap tests. The results demonstrate that the Chemring Nobel RS‐RDX retain the insensitivity towards shock during ageing and show no degradation at all. Accelerated ageing testing of RS‐HMX has also been performed and shows no degradation in the shock sensitivity.     

纳米HMX/微米RDX复合炸药撞击感度的性能研究

在超声波的环境下制备了不同配比的纳米HMX(奥克托今)/微米RDX(黑索今)复合炸药,并对纯RDX炸药和自制炸药的撞击感度进行了比较。结果发现,在实验配比范围内,纳米HMX/微米RDX复合炸药比纯RDX炸药敏感,且随HMX含量的增加,撞击感度降低。     

RDX和HMX的大气压电喷雾电离质谱分析

用液相色谱-大气压电喷雾电离-质谱（LC-ESI-MS）联用技术分离检测RDX和HMX混合物。由反相高效液相色谱法在C18柱上分离了RDX和HMX,检测在225nm处进行,流动相为甲醇／水（V（甲醇）：V（水）=50：50）,流速为0．2mL／min。分析了影响结果的因素,研究了通过诱导碰撞裂解（CID）电压调节RDX和HMX特征碎片离子的毛细管出口（CapEx）电压、pH值、电离方式和干燥气体温度等对其质谱图的影响。结果表明,用负离子检测模式,当CapEx电压为-100V、pH值为8时,可以得到比较理想的质谱图,可观察到RDX和HMX分子离子峰[M-H]^-、加合离子[M-H＋H2O]、[M-H＋2H2O]^-、[M-H＋NO2]^-、[M-H＋62]^-和其他特征碎片离子。根据CID技术得到的RDX和HMX的分子离子,加合离子和特征碎片离子,易确定RDX和HMX的结构。     

Generation of Free Radicals in RDX and HMX Compositions

Efforts to generate detectable concentrations of free radicals in explosives, binders, and their mixtures are described. Radicals were readily produced in polycaprolactone and polyethylene glycol binders at liquid nitrogen temperature using stresses as low as 0.4 kbar. These radicals were all of the peroxy type, and presumably formed by reaction of mechano-radicals with oxygen present in the polymer. No mechano-radicals were observed from HMX or RDX using samples cooled to liquid nitrogen temperature and applied stresses up to 4 kbar. In neither impacted samples that failed to explode nor the residues remaining after a partial explosion were radicals detected by ESR. Low temperature γ-irradiation of these materials was also carried out. Free radical signals originating in both the polymer and the explosive could be identified. The reactivity of NO₂ radicals from γ-irradiated HMX is enhanced in the presence of binder. In γ-irradiated HMX/polycaprolactone mixtures, the NO₂ radical anneals rapidly at 150 K, versus 240 K for HMX alone. Evidence is presented to suggest that the relatively stable NO₂ radical (such as produced by γ-irradiation) in HMX does not play a dominant role in mechanical initiation.     

Anaerobic biodegradation of RDX and HMX with different co-substrates☆

Simulated wastewater of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) was treated under anaerobic conditions with co-substrates such as ammonium chloride, dex-trose, sodium acetic, sodium nitrate and sulfate. The results showed that with nitrogen compounds such as ammonium chloride added as co-substrate, no significant change was observed, indicating that the molar ratio of N/C for RDX and HMX is sufficient for biodegradation. With the addition of dextrose and acetate to the system, biodegradation efficiency was enhanced greatly. For example, with dextrose as the co-substrate, degradation efficiency of 99.1%and 98.5%was achieved for RDX and HMX, respectively, after treatment for 7 days. When so-dium acetic was used as the co-substrate, the enhancement of degradation percentage was similar, but was not as high as that with dextrose, indicating the selectivity of RDX and HMX to co-substrate during anaerobic degrada-tion. With sodium nitrate as the co-substrate, the degradation efficiency of RDX or HMX decreased with the increase of salt concentration. Sodium sulfate has no significant effect on the biodegradation of RDX and HMX. A wel-selected co-substrate should be employed in applications for degradation of RDX and HMX wastewaters.     

TNT在HMX和RDX中的非等温结晶动力学

采用差示扫描量热仪(DSC)研究了TNT在HMX和RDX两种不同介质中的非等温结晶行为.结果表明,在HMX和RDX中加入少量HNS后都能降低TNT的过冷度,消除结晶过程的自加热.利用Avrami方程得到TNT在不同介质中的结晶动力学的指数n分别为2.76和2.86.通过Avrami-Ozawa方程获得了两种体系结晶过程的Ozawa指数m以及反映结晶速率快慢的温度函数F(T).同时,用Ozawa方程和Kissinger方程计算了结晶的活化能Ea和指前因子lnA,并与获得的结果进行了比较.