Aging behavior of the reactive chemicalscontaining system

炸药在长期贮存下的老化会引起实际性能的变化或意外爆炸。本文以红铅/硅铁/三硫化锑、硝酸纤维素为延迟剂，以硝酸铵和聚氨酯为粘结剂的复合固体推进剂为老化模型样品。实验方法是在略高于室温的温度下进行加速老化试验。所得结果如下：红铅/硅铁/三硫化锑的延迟成分老化导致燃烧速率降低，这与红铅与三硫化锑的低温反应有关。另一方面，硝酸铵、铝和叠氮化缩水甘油酯结合剂组成的复合固体推进剂老化后，由于硝酸铵和结合剂的氧化中间体形成酸性物质，燃烧速度加快。最后，硝酸纤维素在酸性混合物中经过长时间的诱导后发生了自催化降解，这归因于反应中间体的形成。从老化机理和温度依赖性出发，提出了预测常温下炸药老化行为的一般思路。

The aging under long term storage of explosives causes a change in a practical performance or an incidental explosion. In this paper, a delay composition of red lead/ ferrosilicone/antimony trisulfide, nitrocellulose in acid mixtures and a composite solid propellant consisted of ammonium nitrate and polyurethane binder were selected as model sample of aging. As an experimental method, accelerated aging tests carried out at the temperature little higher than a room temperature were adopted. The results obtained are as follows.The delay composition of red lead/ ferrosilicone/ antimony trisulfide caused the decreased in burning rate by aging, which involved the low temperature reaction of red lead with antimony trisulfide. On the other hand, the burning rate of a composite solid propellant consisted of ammonium nitrate, aluminum and glycidyls azide binder increased after aging by the formation of acidic substance from ammonium nitrate and an oxidized intermediate of binder. At last, nitrocellulose in acid mixture caused a sutocatalytic degradation after a long induction period, which was ascribed to the formation of reactive intermediate. From the mechanisms and the temperature dependence of aging, a general idea will be presented to predict the aging behavior of explosives under an normal temperature.