HAN-基凝胶推进剂的热分解反应动力学

摘要

In order to study the thermal decomposition characteristics of hydroxylamine nitrate(HAN ) based gel propellant ,the thermal decomposition of two kinds of HAN‐based gel propellant samples containing polyvinyl alcohol(PVA) with different mass was tested by differential scanning calorimeter(DSC) and thermogravimetric analyzer(TGA) .A double‐base propellant was chosen to be compared with this propellant .The thermal decomposition process of HAN‐based gel propellant and double‐base propellant was analyzed and kinetic parameters of their thermal decomposition reaction were obtained .Activation energy was calculated by an isoconversional method .The critical temperature of thermal explosion and self accelerating decomposition temperature were calcu‐lated by Zhang‐Hu‐Xie‐Li method .Malek method is used to infer the most probable mechanism function of thermal decomposition reaction .Results show that the thermal decomposition of HAN‐based gel propellant is a continuous exothermic process and has a small amount of residue .The activation energy is about 100 kJ/mol .The critical temperature of thermal explosion and self accelera‐ting decomposition temperature increase when the content of PVA increases .HAN‐based gel propellant has good thermal stability compared with thermal decomposition parameters of double‐base propellant .%为研究 HAN‐基凝胶推进剂的热分解特性，利用差示扫描量热仪（DSC）和热重分析仪（TGA）对两种含不同质量聚乙烯醇（PVA ）的 HAN‐基凝胶推进剂样品进行热分析试验，并与一种双基推进剂进行对比。分析了HAN‐基凝胶推进剂和双基推进剂的热分解过程，得到热分解反应的动力学参数；采用等转化率法计算了活化能，采用Zhang‐Hu‐Xie‐Li等方法计算出热爆炸临界温度和自加速分解温度。采用Malek法推断出两种 HAN‐基凝胶推进剂样品的热分解反应的最可几机理函数。结果表明，HAN‐基凝胶推进剂的热分解是一个连续的放热过程，热分解较为彻底，残渣较少，活化能约为100 kJ／mol。当PVA含量增加时，其热爆炸临界温度和自加速分解温度升高。与双基推进剂相比，HAN‐基凝胶推进剂具有较好的热安定性。