Transition Metal Carbohydrazide Nitrates: Burn-rate Modifiers for Propellants

Abstract

This paper discusses the synthesis and characterisation of cobalt (Co), nickel (Ni) and copper (Cu) carbohydrazide nitrates. In differential scanning calorimetry (DSC), the complexes exhibited exothermic decomposition indicating their energetic nature. The commencement of decomposition was observed at 220 °C for Ni complex, and at 160 °C for Co complex whereas that of Cu complex occurred at 75 °C. In view of the better thermal stability, Ni and Co complexes were selected for further study. The activation energy of decomposition of Ni and Co complexes were found to be 47 kcal/mol and 60 kcal/mol respectively. Impact and friction sensitivity test results revealed relatively lower vulnerability of carbohydrazide cobalt nitrate. Its incorporation in an ammonium perchlorate (AP)-based composite propellant led to 9-19 per cent enhancement whereas that of carbohydrazide nickel nitrate resulted in 28-74 per cent enhancement in burning rates in the pressure range 1.9 MPa to 8.8 MPa. Exothermic decomposition of the coordination complexes on propellant surface and involvement of metal at molecular level formed on decomposition of the complexes in combustion environment of composite propellant may be attributed to the catalytic effect of this class of compounds on the lines of reported literature.

Metal complexes driven from Schiff bases and semicarbazones for biomedical and allied applications: a review

“…; in pharmaceuticals; and as catalyst [53] They are also used in dyes [54], polymers, [54] as well as they are applied in nanotechnology [55], laser [56], transistor [57], in defense as gas generating agents [58], and pyrotechnic mixtures [59]. ; in pharmaceuticals; and as catalyst [53] They are also used in dyes [54], polymers, [54] as well as they are applied in nanotechnology [55], laser [56], transistor [57], in defense as gas generating agents [58], and pyrotechnic mixtures [59].…”

“…For example some Ni NPs are considered as anode materials for rechargeable batteries, ethanol fuel cell, and a fine substitute for a noble metal used in the internal electrodes of multilayer ceramic capacitors [160]. Bushuyev et al [58] have reported the energetic compounds of type [CuX 2 (C 7 Similarly, some other transition metal complexes Co, Ni, and Zn of carbohydrazide with perchlorate salt were investigated by Talawar et al [162] where they reported that Co and Ni complexes were superior detonants as compared with lead azide and mercuric fulminate in terms of low vulnerability. It is documented that they are used as primary explosives [161e163], burning rate modifiers [57], and also in gas generating agents, [164e166].…”

New Energetic Complexes of Copper(II) and the Acetone Carbohydrazide Schiff Base as Potential Flame Colorants for Pyrotechnic Mixtures

“…Complexes of carbohydrazide with transition metals such as nickel, cobalt, cadmium, and copper have been studied for a variety of applications including their use as primary explosives, [4][5][6] gas generating agents, [7][8][9] and burning rate modifiers. [10] An alternative application for this class of materials would be flame colorants for use in pyrotechnics. [11][12][13] To this end copper complexes of carbohydrazide should be viable candidates that can be used to generate blue and green flame colors, which are difficult to obtain.…”

Ferrocene-containing energetic compounds as ammonium perchlorate thermal decomposition ballistic modifiers

“…Азотосодержащие энергонасыщенные материалы имеют большое количество связей N-N и C-N и, следовательно, большую положительную теплоту образования. Низкое содержание углерода и водорода в этих соединениях дает тройной положительный эффект: повышает плотность соединений, позволяет легко получить хороший кислородный баланс и производит большее количество молей газообразных продуктов в расчете на 1 грамм энергонасыщенных материалов [12]. Гидразины, азиды, тетразолы, содержащие большое количество азота, могут быть использованы в качестве энергонасыщенных материалов.…”