Differences of thermal decomposition behaviors and combustion properties between CL-20-based propellants and HMX-based solid propellants

  • Shuiping ZhouEmail author
  • Xiaoyang Zhou
  • Gen TangEmail author
  • Xiang Guo
  • Aimin Pang


Differences of thermal decomposition characteristics and combustion properties between CL-20-based propellants and HMX-based propellants were researched by combination of theory and practice. Burning rates and burning rate pressure exponents of CL-20-based propellants were much higher than those of HMX-based propellants, when contents and particle sizes of CL-20 and HMX were identical. The thermal decomposition of CL-20 and CL-20-based propellants was systematically studied by comparison of HMX and HMX-based propellants. HMX melted firstly at 198.53 °C and then decomposed violently at 284.3 °C, while CL-20 only decomposed violently at 246.9 °C without any melting peak, and the heat released from decomposition of CL-20 was much higher than that of HMX. Thermal decomposition of CL-20 or HMX could be greatly enhanced by GAP. CL-20 could accelerate the high-temperature decomposition of AP, whereas the decomposition of HMX was greatly enhanced by AP. Mole ratio of [NO2]/[N2O] in decomposition gas products of CL-20 was 3.07, whereas the result for HMX was 0.43. More oxidative gases were generated for CL-20 or CL-20-based propellants. Molar reaction heat in luminescent flame zone and dark zone for CL-20-based propellants was much higher than that for HMX-based propellants, resulting in a higher burning rate for CL-20-based propellants. Value of [NO2]/[N2O] for gas-phase products of thermal decomposition of CL-20/ammonium perchlorate (AP) mixed system was also much higher than of HMX/AP mixed system, resulting in more oxidative gases, such as NO2, involved in the thermal decomposition and combustion of CL-20-based propellants with ammonium perchlorate, further leading to higher burning rates of CL-20-based propellants.


CL-20 Thermal decomposition Combustion properties Solid propellants Oxidative gases 



The work was supported by the Natural Science Foundation of China (Grant No. 51701067).

Compliance with ethical standards

Conflict of interests

There are no conflicts of interest to declare.

Supplementary material

10973_2019_9004_MOESM1_ESM.pdf (441 kb)
Theoretical calculation of thermal decomposition behaviors of HMX and CL-20 was demonstrated in Supporting Information. (PDF 440 kb)


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.Science and Technology on Aerospace Chemical Power LaboratoryHubei Institute of Aerospace Chemical TechnologyXiangyangChina
  2. 2.The Fourth Academy of China Aerospace Science and Technology CorporationXi’anChina

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