Synthesis, properties and application of ferrocene-based compounds as burning rate catalysts in composite solid propellant

Ammonium perchlorate (AP) is commonly used as an oxidizer in composite solid propellant (CSP) and its decomposition temperature directly affects the combustion performance of CSP. Adding burning rate catalysts (BRCs) is the most effective way to catalyze the thermal decomposition of AP and increase the burning rate (BR) of CSP. Ferrocene (Fc) and its derivatives are the hot choice of scientists to use as BRCs but controlling its migration in CSP on prolonged storage still remains a challenge, which can lead to a catastrophic situation. Here, we synthesized six Fc-based morpholine (Fc-MPNs) compounds to catalyze the thermal decomposition of AP and address the migration problem. Several spectroscopic techniques, including 1 H NMR, FT-IR and UV–visible spectroscopy were used to confirm the structures of the prepared Fc-MPNs. The results revealed that amongst all the prepared catalysts, Fc-MPN-6 showed the best anti-migration performance and Fc-MPN-3 showed the superior catalytic performance. Cyclic voltammetry (CV) studies showed efficient electron transfer. Combustion test exhibited improved flame morphology and BR. Scanning electron microscopy (SEM) analysis of the combusted products provided insights into the morphology of the combusted products. Notably, the synthesized Fc-MPNs showed better performance in comparison with Fc and Cat, highlighting their potential applications in spacecraft propulsion and missile systems.