Thermal study of APNIMMO/CL-20 based propellants fabricated by 3D printing

Highlights: • APNIMMO/CL-20 propellant was 3D printed by photopolymerization method. • Thermal behavior and decomposition kinetics have been investigated. • Interesting two overlapped decomposition peaks were studied. • APNIMMO has a significant effect on activation energies and reactivity. Energetic photocurable binder has been developed to improve the energy content of 3D printed propellants. Thermal decomposition study is a significant part for evaluating novel binders and relevant propellants. In this paper, acrylate-terminated poly-3-nitratomethyl-3-methyloxetane (APNIMMO) and a series of formulas containing 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) were prepared by the stereolithography (SLA) printing. The thermal performance and decomposition kinetics were investigated by means of the nonisothermal DSC (differential scanning calorimetry) techniques. Additionally, simultaneous DSC-FTIR were employed to corroborate the thermal analysis results. The compatibility of the various admixtures was confirmed through an additional kinetic study for which the Arrhenius parameters were computed by different isoconversional Kissinger method and modified Kissinger-Akahira-Sunose (KAS) method. The decomposition products were also detected by in-situ DSC-MS-FTIR. The obtained results from the different techniques are presented and discussed.