Analyzing the pyrolysis mechanism of advanced composites based on nitrotriazolone and energetic cellulose-rich polymers

This study investigated the structure, thermal decomposition, and mechanism of nitrotriazolone (NTO)-based composites. Three types of energetic composites namely, nitrocellulose (NC)/NTO, microcrystalline nitrocellulose (MCCN)/NTO, and carbamate microcrystalline cellulose nitrated (M3CN)/NTO were prepared. The obtained results revealed that NTO particles were homogeneously dispersed or embedded within the modified or unmodified nitrated polymeric chains. This dispersion effectively inhibited the crystal growth of NTO particles, resulting in submicron-sized particles. In addition, the thermolysis of NC, MCCN, and M3CN remained unchanged according to thermal analysis results, while the second temperature peak was significantly lower than that of raw NTO. Notably, the thermolysis of the nitrated polymers (NC, MCCN, and M3CN) occurs independently when combined with NTO. It was found that the release of gaseous species during the initial decomposition phase significantly influenced the thermal profile of NTO, thereby altering its decomposition mechanism. Thermogravimetric analysis coupled with fourier transform infrared spectroscopy (TGA-FTIR) findings highlighted the significant influence of nitrated polymer types on the gaseous products of NTO decomposition, affecting the intensity and the type of nitrogen oxides generated during pyrolysis. These results present a promising fabrication strategy for utilizing NTO-based energetic composites in high-energy propellants and explosives.