title: Synthesis, characterization and thermal studies of (Ni/Co) metal salts of hydrazine: potential initiatory compounds.
abstract: Nickel hydrazinium nitrate (NiHN) and cobalt hydrazinium nitrate (CoHN) were prepared by reacting their respective metal nitrates with hydrazine hydrate at 25 and 65 degrees C. The compounds were characterized by metal content and infrared (IR) spectroscopy. Differential thermal analysis (DTA) results suggest that the nickel complex is relatively more stable than the cobalt complex. The activation energy determined by DTA and ignition delay measurements corresponds to an energy of activation (E(a)) of 80+/-4 kJ/mol for NiHN and that of 150+/-8 kJ/mol for CoHN. Thermo gravimetry (TG) also revealed more rapid decomposition of NiHN than that of CoHN in the temperature region of 215-235 degrees C. High temperature Fourier transform-infrared (FT-IR) studies indicated rupture of the Ni-Co-N bond as the primary step in the thermolysis. As regards sensitivity to mechanical stimuli, NiHN was found to be less impact sensitive while CoHN exhibited less friction sensitivity. The study revealed that NiHN could be used alone as well as in combination with oxidizer/fuel as initiators depending upon the specific requirements. The effect of silver azide and glass on the sensitization of NiHN was also studied. CoHN appears to be an effective ballistic modifier in enhancing burning rates of composite propellants.
authors.affiliation: High Energy Materials Research Laboratory, Pune 411 021, India. root@drerdl.ren.nic.in
authors.forename: J S
authors.initials: JS
authors.lastname: Chhabra
authors.forename: M B
authors.initials: MB
authors.lastname: Talawar
authors.forename: P S
authors.initials: PS
authors.lastname: Makashir
authors.forename: S N
authors.initials: SN
authors.lastname: Asthana
authors.forename: Haridwar
authors.initials: H
authors.lastname: Singh
mesh_terms: D002273:Carcinogens / Q000737:chemistry*; D003035:Cobalt / Q000737:chemistry*; D015386:Hazardous Substances; D006834:Hydrazines / Q000737:chemistry*; D007700:Kinetics; D009532:Nickel / Q000737:chemistry*; D012492:Salts / Q000737:chemistry; D013055:Spectrophotometry, Infrared; D013696:Temperature
chemical_list: D002273:Carcinogens; D015386:Hazardous Substances; D006834:Hydrazines; D012492:Salts; C029424:hydrazine; D003035:Cobalt; D009532:Nickel