Effect and mechanism of reductive polyaniline on the stability of nitrocellulose

The search for new green and efficient stabilizers is of great importance for the stabilization of nitrocellulose (NC). This is due to the shortcomings of traditional stabilizers, such as high toxicity. In this study, reduced polyaniline (r-PANI), which has a similar functional structure to diphenylamine (DPA) but is non-toxic, was prepared from PANI based on the action with N₂H₄ and NH₃–H₂O, and used for the first time as a potential stabilizer for NC. XPS, FTIR, Raman, and SEM were used to characterize the reduced chemical structure and surface morphology of r-PANI. In addition, the effect of r-PANI on the stabilization of NC was characterized using DSC, VST, isothermal TG, and MMC. Thermal weight loss was reduced by 83% and 68% and gas pressure release by 75% and 49% compared to pure NC and NC&3%DPA, respectively. FTIR and XPS were used to characterize the structural changes of r-PANI before and after reaction with NO₂. The 1535 cm⁻¹ and 1341 cm⁻¹ of the FTIR and the 404.98 eV and 406.05 eV of the XPS showed that the –NO₂ was generated by the absorption of NO₂. Furthermore, the quantum chemical calculation showed that NO₂ was directly immobilized on r-PANI by forming –NO₂ in the neighboring position of the benzene ring.