Abstract
CL-20 is an attractive HEM having density (>2 g cm-3) and velocity of detonation (9400 m s-1) superior to HMX (1.9 g cm-3 and 9100 m s-1). During this study, CL-20 was synthesized to establish viability of efficient synthesis method. The compound synthesized at HEMRL was characterized by FTIR, 1H NMR and elemental analysis. Thermal studies (dynamic DSC and isothermal TG) were undertaken to determine kinetic parameters and understand the decomposition patterns. An attempt is made to explain the mechanism of decomposition of CL-20 on the basis of the data obtained by the authors and findings of other researchers. The activation energy values obtained during this work by adopting various approaches are close to the values reported for N-NO2 bond cleavage suggesting that it is global rate determining process rather than the collapse of cage structure. Mass spectra also provides evidences in this regard. Monitoring of decomposition products at high temperature supports these findings and brings out that NO2 initiates secondary decomposition processes because of entrapment in cage structure.
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Geetha, M., Nair, U.R., Sarwade, D.B. et al. Studies on CL-20: The most powerful high energy material. Journal of Thermal Analysis and Calorimetry 73, 913–922 (2003). https://doi.org/10.1023/A:1025859203860
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DOI: https://doi.org/10.1023/A:1025859203860