CL-20 Evaporative Crystallization under Reduced Pressure.

Maksimowski, Paweł; Tchórznicki, Paweł

The effect of parameters of the CL-20 crystallization process carried out by solvent removal by evaporation in vacuo on shape, polymorph type, crystal size, and on their shock sensitivity was studied. The CL-20 crystallization process by this technique was shown to allow a precise control of the crystallization process parameters and of the process run. The o-xylene/ ethyl acetate system proved to be highly effective. Selecting suitable values of the parameters such as: pressure, process time, temperature, stirring rate, CL-20 crystals were obtained in the ε form (even with no need for inoculation of the crystallization system with polymorph ε seeds) and of the shape close to a spherical one. The crystal growth modifiers added allowed to additionally control the shape and size of the CL-20 crystals formed and to produce crystals of reduced impact and friction sensitivity.

CRYSTALLIZATION; EVAPORATION (Chemistry); POLYMORPHISM (Crystallography)

Propellants, Explosives, Pyrotechnics, 2016, Vol 41, Issue 2, p351

0721-3115

Academic Journal

10.1002/prep.201500201