龙骨状纳米结构TATB的构筑与热分解动力学研究

Construction and Thermal Decomposition Kinetics of the Keel-like Nanostructure TATB

基于纳米结构对材料性能的调控,采用溶剂/非溶剂法来构筑三氨基三硝基苯(TATB)的纳米结构。通过强的非溶剂效应和温度效应,制备得到龙骨状纳米结构TATB。采用场发射扫描电镜(FE-SEM)与透射电镜(TEM)观察样品的微观形貌,X射线衍射分析(XRD)和激光粒度分析仪测试样品的晶相和粒径分布。结果表明,所得样品整体呈龙骨状结晶,晶型较原料TATB未发生改变,粒径分布为70～400 nm。不同升温速率下的热分析结果表明,龙骨状TATB的热分解峰温较原料TATB提前1.54～2.91℃,表观活化能(E_a)提高0.29 kJ·mol^(-1),对热刺激的敏感性降低;通过微分法计算得出龙骨状TATB的热分解机理为随机核化,每一粒子有一个核,而原料则为三维扩散,其动力学方程为球形对称的Jander方程。

Based on the regulating of nanostructure on the properties of materials,the nanostructure of 1,3,5-triamino-2,4,6-trinitrobenzene(TATB)was constructed by solvent/non-solvent method.Through strong nonsolvent effect and temperature effect,the keel-like nanostructure TATB was prepared.The microstructure of the sample was observed by field emission scanning electron microscopy(FE-SEM)and transmission electron microscopy(TEM)and the crystal phase and particle size distribution of the sample were measured by X-ray diffraction(XRD)and Laser Particle Size Analyzer.The results show that the whole morphology of obtained sample is keel-like crystalline.And the crystal form does not change compared with the raw material and the size distribution is from 70 to 400 nm.The thermal analyses at different heating rates show that the thermal decomposition peak temperature of keel-like nanostructure TATB is 1.54-2.91℃ earlier than that of raw TATB,the apparent activation energy(Ea)is increased by 0.29 kJ·mol^-1,and the sensitivity to thermal stimulation is decreased.The thermal decomposition mechanism of keel-like nanostructure TATB obtained by differential method calculationis random nucleation(a core for a particle),whereas the raw material is three-dimension diffusion and its kinetic equation is Jander equation with sphericalsymmetry.