The degradation of a mixture of guanidine nitrate (GN) and basic copper nitrate (BCN), which is used as a gas generant, was studied under the application of heat and water. The degradation that occurs was observed using an ultraviolet-visible absorption spectrometer and X-ray diffraction (XRD) analysis. The results showed a change in the chemistry of BCN and the generation of cupric oxide (CuO). The chemical reaction produced the degradation of BCN at 75℃. In addition, the GN/BCN exhibited deliquescence, implying that the mixture contained a large amount of water when it reacted with humid air; it was also observed that GN reduces the rate of degradation of BCN. The mechanism for reduction was considered and confirmed by adding nitrate or guanidine salts to an aqueous solution of BCN, which was subjected to heat. The results of XRD showed that the rate of degradation decreased because of the presence of nitrate ion, while the guanidine ions did not produce any effects of reduction. This study has revealed that the effect of the reduction of GN originated from the nitrate ions and depended on the quantity of GN.
guanidine nitrate, basic copper nitrate, aging, water absorption, humidity