叠氮化银起爆药连续化合成芯片的设计与应用研究

Design and Application Investigations of a Microfluidic Chip for the Continuous Synthesis of Silver Azide Primary Explosive

针对叠氮化银(AgN3,简写为SA)起爆药合成过程对于反应溶液快速混合的要求,设计制作了连续反向旋T形微混合芯片,并采用Ansys Fluent仿真模拟软件对芯片结构及反应物流速等因素对混合效率的影响规律进行了研究,优化获得了高效微混合芯片结构。使用该芯片进行了纳米SA起爆药的连续化合成,通过扫描电子显微镜(SEM)、X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、差示扫描量热(DSC)研究了SA起爆药的形貌、成分结构与热性能。结果表明:当微混合芯片的通道尺寸为1 mm,对撞角度180°,反应物流速4 mL·min^(-1)以上时,可获得接近100%的混合效率。通过调节反应物流速、浓度和添加表面活性剂,可有效调控产物粒径及其分布,且反应产物主要成分为正交晶系的AgN3晶体。相较常规方法,使用微流控方法制备的SA起爆药放热峰温度由365.2℃提前到358.2℃(降低7℃),且放热量由851.6 kJ·kg^(-1)升高到976.7 kJ·kg^(-1)(升高14.7%),表明微流控方法制备的SA起爆药具有更高的反应活性和能量。

To meet the demand for rapid mixing of the reaction solution in the synthesis of silver azide(AgN3,SA)primary explo⁃sives,a continuous reverse⁃rotating T⁃shaped micro⁃mixing chip was designed and fabricated.The influence of chip structure and reactant flow rates on mixing efficiency was investigated using Ansys Fluent simulation software,leading to optimization of an efficient micro⁃hybrid chip structure.This optimized chip was employed for the continuous synthesis of SA primary explo⁃sives.The morphology,compositional structure,and thermal properties of the resulting SA primary explosives were character⁃ized using scanning electron microscopy(SEM),X⁃ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and differential scanning calorimetry(DSC).It was observed that a near 100%mixing efficiency could be achieved when employing a micro⁃mixing chip with a channel size of 1 mm,collision angle of 180°,and reactant flow rate above 4 mL·min^(⁃1).By adjusting the flow rate,concentration,and surfactant content of the reactants,uniform morphology with narrow particle size distribution could be obtained for the SA primary explosives;their main component consisted of AgN3 crystals exhibiting an orthorhombic crystal system.Compared to the conventional methods,the exothermic peak temperature decreased from 365.2℃to 358.2℃(a reduction by 7℃)while the exothermic amount increased from 851.6 kJ·kg^(-1)to 976.7 kJ·kg^(-1)(an increase by 14.7%)when utilizing microfluidic preparation techniques for SA primary explosives,indicating enhanced reactivity and energy.