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Submicron hexanitrohexaazaisowurtzitane ( CL-20 ) is prepared using HLG-50 pulverized machine. The laser particle size analyzer and SEM are used to characterize the particle size, size distribution and morphology of sample. The polymorph and purity of CL-20 particles are characterized by Fourier transform infrared spectrometer, laser Raman spectrometer, XRD and HPLC, respectively. The TG/DSC simultaneous thermal analyzer is used to study the thermal decomposition of CL-20. The shock sensitivity of samples are studied. The results show that CL-20 particles are pseudo-spherical with an average particle size (d50) of 210 nm. The polymorph of submicron CL-20 is consistent with that of the raw ε-CL-20. Compared with the raw CL-20, the thermal decomposition peak temperature of the submicron CL-20 is decreased slightly, and the shock sensitivity of the submicron CL-20 is considerably reduced by 53. 1% . That implies the obvious reduction in the shock sensitivity of CL-20. [ABSTRACT FROM AUTHOR]

The conventional way takes a long time to determine the uniformity of absorbent powders in blend procedure, which is an obstacle to automation and continuation of production process of solid propellant. Near-infrared (NIR) analysis is proposed to solve that problem. A micro NIR spectrometer is used to collect the spectra of absorbent powders that are stirred continually, and the moving block of standard deviation (MBSD) algorithm is utilized to quantitatively analyze the difference between spectra of absorbent powders. The uniformity and endpoint are presented from the standard deviation-time curve. In addition, the accuracy of NIR analysis on the collected samples is confirmed through high performance liquid chromatography (HPLC). The results show that NIR analysis is efficient, eco-friendly and safe. It is feasible to apply NIR analysis to monitor the blend uniformity of modified double-base absorbent powders online and determinate the endpoint of blend process in real-time. [ABSTRACT FROM AUTHOR]