机械球磨法制备纳米HNS及其热分解性能

摘要

To refine the hexanitrostilbene(HNS), nanometer HNS explosive with average particle size of 94.8 nm was prepared by a high energy ball milling method.The characteristics and analysis of the HNS sample were performed by scanning electron microscopy(SEM), X-ray diffractometry(XRD), infrared(IR) spectroscopy, X-ray photoelectron spectroscopy(XPS), DSC-IR analysis and 5s explosion temperature.Results show that after ball milling, the micro morphology of the explosive is nearsr-pherical, and the particle reveals a normal distribution.The mechanical ball milling action does not change the original crystal form, molecular structure, and surface elements of HNS, showing that mechanical milling is a kind of reliable method for fabrication of nanometer HNS.The apparent activation energy of thermal decomposition of nanometer HNS is 12.4 kJ·mol-1 higher than that of raw HNS, indicating that the activation of nano HNS molecules requires a higher energy.After heating, nanometer HNS decomposes into a large number of CO2 and a small amount of H2O, while the N element is present in the non polar N2 molecule.The 5 s explosion temperature of nanometer HNS is 12.2 ℃ higher than that of raw HNS, meanting than the nanometer HNS has lower thermal sensitivity.%为细化六硝基茋(HNS),采用高能球磨法制备出了平均粒径为94.8 nm的纳米HNS炸药.用扫描电镜(SEM)、 X射线衍射(XRD)、红外(IR)、X光电子能谱(XPS)、DSC-IR和5 s爆发点,进行了HNS样品的表征和分析.结果表明,球磨后炸药的微观形貌呈类球形,粒度呈正态分布.机械球磨作用并未改变HNS原有的晶型、分子结构、及表面元素,说明该制备纳米HNS方法十分可靠.纳米HNS热分解的表观活化能较原料HNS高12.4 kJ·mol-1,说明纳米HNS分子的活化需要更高的能量.纳米HNS被加热后分解成了大量的CO2和少量H2O,而N元素以非极性的N2分子存在.纳米HNS的5s爆发点(T5s)较原料高12.2 ℃,说明纳米HNS具有更低的热感度.