With the aim of developing ammonium nitrate (AN) for conventional use as a new oxidizer for gas-generating agents in automobile airbag systems, the combustion characteristics of model gas-generating agents consisting of guanidine nitrate (GN), basic copper nitrate (BCN), and AN were investigated. Based on the results of strand burner tests, four conclusions were obtained : (1) the presence of BCN allows ignition of GN/AN mixtures, which do not ignite without BCN, and sustained combustion at lower pressure (about1MPa) ; (2) the nature of the combustion residues from the GN/AN/BCN mixtures varied depending on the combustion conditions and the mixing ratio of the sample mixture ; (3) the value of the pressure exponent n was smaller (0.41-0.45) in mixtures with a high AN content or when the test was conducted under low pressure (<5MPa), but larger (0.67-0.77) in mixtures with a low AN content or when the test was conducted under high pressure (>5MPa) ; (4) the combustion wave could be divided into four regions based on the temperature and phase of the mixture. Based on these results, the model suggested for the mechanism of combustion was one in which diffusion combustion and homogeneous combustion co-exist.
自動車用エアバッグガス発生剤の新規酸化剤候補として硝酸アンモニウム（以下，ANと略記）の実用化を目指し，硝 酸グアニジン（以下GNと略記），塩基性硝酸銅（以下，BCNと略記），ANからなるモデルガス発生剤の燃焼挙動が検討 された。ストランド燃焼試験の結果より，以下の結論が示された。（１）BCNの添加がGN/AN混合物の着火を実現し，低圧 条件下（約１MPa）における持続燃焼を実現すること。（２）GN/AN/BCN混合物の燃焼残渣の様子が燃焼条件と試料の混 合組成によって異なる事。（３）圧力指数は高AN含有量または低圧下（５MPa以下）では０．４１から０．４５となり，一方で低AN 含有量または高圧下（５MPa以上）では０．６７から０．７７となること（４）燃焼波は温度と相状態から４つの領域に分けられる こと。以上の結果から，拡散燃焼と均質燃焼が共存する燃焼機構モデルが提案された。
ammonium nitrate, combustion, linear burn rate.