Preparation and Analysis of ε-CL-20 Polymorph and Evaluation of Parameters Affecting its Particle Size

The HNIW with the chemical name 2,4,6,8,10,12-hexanitro 2,4,6,8,10,12- hexaazaisowurtzitane (more commonly known as CL-20) and with cage structure is the most powerful non-nuclear explosive materials. CL-20 can exist as four different polymorphic phases (α, β, γ and ε) at ambient temperature and atmospheric pressure having different density and sensitivity. ε morphology, with more density is less sensitive and more appropriate for military applications. In this paper, both the synthesis and crystallization methods for the preparation of ε-CL-20 is investigated and the effects of different parameters (solvent, temperature, and stirring rate) on the particle size of ε-CL-20 prepared from crystallization method were studied. It is shown that the best solvent for crystallization of ε-CL-20 is ethyl acetate. Heptane and chloroform are more convenient as antisolvents. ε-CL-20 was analyzed by different techniques as Raman and FTIR, SEM and XRD.