电点火头蘸药过程反应失效分析

为解决某电点火头在蘸药过程发生反应导致点火药失效问题,采用化学分析、DSC热分析、红外光谱分析、X衍射分析技术对影响点火头生产工艺的因素进行综合分析,设计DSC方法模拟反应程度与材料的关系.结果表明,点火药与配漆溶剂丙酮在室温较高时,易发生放热反应,放出的热量加剧反应,从而引起点火药被反应消耗而失效.可通过降低工房温度、缩短蘸药时间、改变配漆溶剂、控制铬酸铅原材料质量等方面改进,以避免点火药失效.     

自催化反应速率方程的导出途径及其在含能材料热行为研究中的应用

提出了经验级数自催化反应速率方程和13个派生式的导出途径。导出了描述自催化反应速率曲线特性[αmax和(dα/dt)max]的方程和反应进度(α)随时间(t)和温度(T)变化的方程。编制了计算自催化反应动力学参数(E、A或E1、A1、E2、A2)、经验级数(m、n、p)和αmax、(dα/dt)max值的计算机程序。提出了描述六硝基六氮杂异伍兹烷(HNIW)自催化分解反应的速率方程和硝化棉(NC)(12.82%、12.97%、13.54%、13.61%、13.86%、13.88%、14.14%N)自催化分解反应的动力学参数——催化系数Kcat、速率曲线特性参数和α随t变化的方程。     

硝化剂及预处理条件对软木NC氮量及其分布影响

以加拿大针叶木为原料、采用硝硫混酸和HNO3/CH2Cl2两种硝化剂分别制备了A、B、C、D级硝化纤维素(NC)样品,通过偏光显微镜分析测试了其含氮量及氮量分布(硝化均匀性)。同时采用不同的高压闪爆预处理条件,对针叶木进行预处理,比较了闪爆对高氮量B、低氮量D级NC的含氮量及氮量分布,系统研究了硝化剂体系组成及原料预处理条件对NC的含氮量及其分布影响规律。结果表明,在同样氮量级别,HNO3/CH2Cl2硝化体系比HNO3/H2SO4/H2O得到的NC氮量分布更均匀,A、B、C与D级NC的均匀性分别提高17.46%、16.98%、16.77%和25.79%;同一硝化剂体系,闪爆有利于硝化剂向软木纤维素纤维束内部扩散,能提高NC含氮量及氮量分布均匀性,B级NC,其均匀性提高6.06%,D级NC则提高7.56%。     

Energetic nitrocellulose coating: effective way to decrease sensitivity and modify surface property of HMX particles

Modifying the surface properties of energetic materials has theoretical and practical significance in the field of their application. In this paper, irregular cyclotetramethylene tetranitramine (HMX) particles were successfully coated by energetic nitrocellulose (NC), leading to the uniform NC-coated HMX particles. As coating materials, energetic (NC was chosen to decrease the sensitivity and modify the surface property of HMX particles, in order to expand their application furthermore. Scanning electron microscopy, laser particle size analysis, energy dispersive spectrometer, and Fourier-transform infrared (FT-IR) spectra were utilized to investigate the morphology, size, and coating quality of NC-coated HMX particles. These results indicated the effective preparation of composites structure. Moreover, the thermal behaviors of NC-coated HMX particles were investigated by simultaneous thermogravimetric and differential scanning calorimetry analysis, coupled with FT-IR and mass spectroscopy. These results showed that NC did not induce chemical properties change of HMX, only physical hydrogen bond was formed in the coating process. Finally, the friction sensitivity, impact sensitivity, and surface properties NC-coated HMX were investigated, and the results suggested that NC-coated HMX particles had better safety and depicted stronger interaction with the binder matrix than original HMX, owing to the stability of NC on the outer layer.     

石油树脂在硝基透明腻子中的应用研究

用名贵木材制作实木家具目的就是要凸显自然花纹。针对市售透明腻子透明性差、花纹被遮盖问题,本文选用C9石油树脂做透明填料制备硝基透明腻子。详述了工艺配方和产品特性;DSC吸放热曲线表明石油树脂相对分子质量范围大,更有利于腻子附着力和打磨性提高;扫描电镜SEM微观形貌图证明用石油树脂制备的硝基透明腻子较普通透明腻子具有更好的透明性、刮涂性和丰满度。干后易打磨,且贮存稳定性好,不会出现漆液分层、桶底沉淀、结团等现象。     

微米级硝化纤维素的制备及性能研究

为了使硝化反应在近似均相的条件下进行,采用对精制棉进行水解处理,用稀酸水解法制得结晶度较为一致的微晶纤维素,再用硝硫混酸进行硝化得到微米级硝化纤维素。用扫描电镜和红外光谱对其微观形貌和结构进行了表征。用DSC分析了其热性能,并测试了其撞击感度和黏度。结果表明,制备微米级硝化纤维素的最佳条件为:硝硫混酸体积比为1∶3,硝化时间30min,硝化温度为35℃。制得的微米级硝化纤维素样品粒度均匀,其特性落高为57.466cm,黏度为478mPa·s,分解峰温达到211.20℃,硝化均匀,含氮量可达12.8%。     

硝化棉生产废水处理工程的启动

采用混凝/两段活性污泥法组合工艺处理硝化棉生产废水,经过一个月左右的调试运行后,高负荷曝气池和CASS池对COD的去除率分别为65%和50%,对BOD5的平均去除率分别为64%和75%,出水水质达到<污水综合排放标准>(GB 8978-1996)的二级标准.     

Alcogel and aerogel of nitrocellulose formed in nitrocellulose/acetone/ethanol ternary system

Nitrocellulose (NC) alcogels were formed in NC/acetone/ethanol ternary system and NC aerogels were prepared from NC alcogels after drying under supercritical CO₂ (scCO2). NC alcogel with lower modulus was formed in the ternary system with a higher ethanol ratio. The densities and porosities of NC aerogels were related directly to the initial ethanol content. The NC aerogels clearly retained the crystalline structure of NC powder. NC aerogels that were formed in the system with higher ethanol content had larger pore size distribution range, larger average pore diameter, and larger mesopore and macropore volume. The thermal decomposition of NC aerogel was more accelerated and more acute compared with NC powders.     

硝化棉气凝胶的微结构及热分解特性

为研究硝化棉(NC)气凝胶的微结构及其与热性能的关系,用溶胶-凝胶法以及超临界干燥法制备了硝化棉气凝胶。用扫描电子显微镜(SEM)、X射线衍射(XRD)、热重-红外联用(TG-FTIR)表征了其微观结构、结晶性及热性能。结果表明:NC气凝胶的微观结构为纳米颗粒堆积成的纳米多孔结构。其结晶遭到破坏,呈非晶无序特征。与NC相比,NC气凝胶的DTG峰温及DSC放热峰温度分别提前7℃和11℃,分解热由1429.87 J·g-1提高至1689.21 J·g-1。     

NC/NG共混体系的分子动力学模拟研究

为研究复合改性双基推进剂（CMDB）基体硝化纤维素（NC）与硝化甘油（NG）之间相互作用的实质,通过构建NC纯物质以及不同质量比的NC/NG共混体系模型,并采用分子动力学模拟的方法,对NC分子链的回转半径及模型中不同原子间的径向分布函数进行了分析。结果发现：NC分子链的回转半径随温度升高而增大的趋势并不明显;而随NG分子数量增多而增大的趋势非常显著。径向分布函数分析表明,NG分子可与NC分子形成氢键而替代NC分子内的氢键,使NC分子内的相互作用力减弱,从而导致NC分子链回转半径增大.