液滴限域结晶制备CL-20/HMX共晶毫米空心球及其性能

Preparation and Properties of Millimeter⁃sized Hollow Spheres for CL⁃20/HMX Co⁃crystal by Droplet Confined Crystallization

为了研究聚集结构对六硝基六氮杂异伍兹烷/奥克托今(CL-20/HMX)共晶性能的影响,采用液滴限域结晶法制备了球形CL-20/HMX共晶。采用场发射扫描电子显微镜(FE-SEM)、X射线粉末衍射(XRD)和傅里叶红外光谱(FT-IR)对共晶样品进行形貌结构表征,并通过热分析、感度和燃烧测试对共晶样品进行性能分析。结果表明,该方法成功制备CL-20/HMX共晶毫米空心球,其直径在1.3~1.85 mm之间,空心率约40%,比表面积为6.890 m^(2)∙g^(-1)。球形CL-20/HMX共晶的放热峰温为245.8℃,热分解活化能(463.02 kJ∙mol^(-1))和热爆炸临界温度(241.28℃)均高于片状CL-20/HMX共晶,热稳定性提高;撞击感度优于原料和片状CL-20/HMX共晶,摩擦感度介于CL-20和HMX之间,但低于片状CL-20/HMX共晶;点火延迟时间小于8 ms,火焰明亮、燃烧高效稳定,而片状共晶、原料及其物理混合物均为无焰燃烧。

In order to investigate the effect of aggregation structure on the properties of hexanitrohexaazaisowurtzitane/octogen(CL-20/HMX)co-crystal,the droplet confined crystallization was used to prepare spherical CL-20/HMX co-crystal.The morphol-ogy and structure of the samples were characterized by field emission scanning electron microscopy(FE-SEM),X-ray powder dif-fraction(XRD)and fourier transform infrared spectroscopy(FT-IR).The properties of the samples were analyzed by thermal anal-ysis,sensitivity and combustion tests.The results show that the spherical CL-20/HMX co-crystal was successfully prepared by this method.The diameter of the spherical CL-20/HMX co-crystal is 1.3-1.85 mm,the hollow ratio is about 40%,and the specific surface area is 6.890 m^(2)·g^(-1).The exothermic peak temperature of spherical CL-20/HMX co-crystal is located at 245.8℃,the thermal decomposition activation energy(463.02 kJ·mol^(-1))and the critical temperature of thermal explosion(241.28℃)are higher than those of flake CL-20/HMX co-crystal,exhibiting the excellent thermal stability of spherical CL-20/HMX.The impact sensitivity is better than that of raw material and flake CL-20/HMX co-crystal,and the friction sensitivity falls between raw CL-20 and HMX,but lower than that of flake CL-20/HMX co-crystal.The ignition delay time is less than 8 ms and the combustion is effi-cient and stable,while the flake CL-20/HMX co-crystal,raw materials and their physical mixture exhibit flameless combustion.The construction of millimeter-sized hollow spheres for CL-20/HMX co-crystal has significantly improved the thermal stability,sensibility and combustion performances.