engleski

Study of Ageing Processes of Double Base Rocket Propellants, Based on Stabilizer Consumption

The aging of double base (DB) rocket propellants is the result of chemical decomposition reaction and physical processes, causing degradation of a number of relevant propellant properties (such as reduction of stabilizer and nitroglycerine (NG) content, reduction of mean molecular mass of nitrocellulose (NC) etc.), which reflects on the reduction of reliable application time of DB propellants. In certain circumstances, the processes of chemical decomposition can take autocatalytic character and lead to the well-known phenomenon of "self-ignition or thermal explosion" of propellant. Consequently, studying of the mechanism and kinetics of the processes that cause propellant aging has great practical and theoretical importance. In order to investigate the aging process of DB rocket propellants, propellant samples were subjected to accelerated aging at elevated temperatures (80, 85 and 90 °C), and the change of the stabilizer/ethyl-centralite content with aging time and temperature were periodically monitored. Change of the ethyl-centralite content was observed using high performance liquid chromatography (HPLC). The results show that ethyl-centralite consumption in conditions of accelerated aging is very intense from the very beginning of aging. The entire ethyl-centralite is depleting after 120 days at 80 °C, followed by the intensive reactions of NC decomposition. The results obtained from kinetic data processing have shown that activation energy of DB propellant decomposition obtained on the basis of ethyl-centralite consumption is 142.98 kJ/mol, which is consistent with available literature values.

activation energy; artificial ageing; double base propellants; kinetics of decomposition; ethyl-centralite; high performance liquid chromatography (HPLC)

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