Ionic Ferrocenyl Coordination Compounds Derived from Imidazole and 1,2,4-Triazole Ligands and Their Catalytic Effects During Combustion

Alkylferrocene-based burning-rate catalysts (BRCs) show conspicuous migration tendency and volatility during prolonged storage and fabrication process of a composite solid propellant. To enhance anti-migration ability of the BRCs, forty novel ionic coordination compounds, [M(L)(4)(H2O)(2)](m)X-n (M = Mn2+, Co2+, Cu2+, Ni2+, Zn2+, Fe2+, Pb2+, Cr3+, Bi3+, or Cd2+; L = ferrocenylmethyl imidazole or ferrocenylmethyl-1,2,4-triazole; X = picrate or trinitroresorcinolate), were synthesized and characterized by FT-IR, UV/Vis, and elementary analysis. Additionally, the crystal structures of six compounds were confirmed by single-crystal X-ray diffraction. The TG analyses revealed that the new compounds show high thermal stability. Cyclic voltammetry studies suggested that theyare irreversible redox systems. Their catalytic activities in the thermal degradation of ammonium perchlorate (AP), 1,3,5-trinitro-1,3,5-triazacyclo-hexane (RDX) and 1,2,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX) were examined by DSC technique. The results indicated that all the new compounds exert great effects on the thermal decomposition of AP and RDX, among them some compounds are more active than catocene. Compound 26 has good catalytic ability in the thermal decomposition of HMX, representing a rare example of the reported ferrocene-based BRCs which show catalytic activity during combustion of HMX.