某四组元HTPB推进剂热分解特性研究

Study on mechanism function and thermal safety of a four component HTPB propellant

针对某型四组元HTPB推进剂的热分解特性,运用微分法和积分法对差示扫描量热法(DSC)和热重分析(TG)试验数据进行了计算。运用Malek法对该型四组元HTPB推进剂的热分解试验数据进行分析,推导出了该型推进剂热分解的最概然机理函数。计算结果表明:该型推进剂的热爆炸临界温度T_(b)=206.59℃,自加速分解温度T_(SADT)=204.86℃,推进剂的指前因子A=5.645×10^(17),推进剂活化能约在(187.30~205.51)×10^(3) J·mol^(-1);该型推进剂热分解反应是一个连续分阶段的自催化n级反应,n=2,拟合计算得到推进剂的动力学方程分别为:dα/dt=3.38×10^(5)(0.179-1.041α+2.593α^(2)-1.792α^(3))/T^(2);推进剂热安全性和热安定性较为良好,但是RDX的加入一定程度上会降低推进剂的热安全性和热安定性。

In order to study the thermal decomposition characteristics of a four component HTPB propellant,the DSC and TG test data were calculated by differential and integral methods.Malek method was used to analyze the thermal decomposition test data of HTPB propellant,and the most probable mechanism function of thermal decomposition of HTPB propellant was calculated.According to the experimental results,the critical temperature of thermal explosion T_(b)=206.59℃,the self-accelerated decomposition temperature T_(SADT)=204.86℃and the pre-exponential factor A=5.645×10^(17)were calculated and the activation energy of propellant was about(187.30~205.51)×10^(3) J·mol^(-1).It is found that the thermal decomposition reaction of the propellant is a continuous,step-by step autocatalytic N-order reaction,n=2.The kinetic equations of the propellant are dα/dt=3.38×10^(5)(0.179-1.041α+2.593α^(2)-1.792α^(3))/T^(2).The results show that the thermal safety and thermal stability of the propellant are good,but the addition of RDX reduces the thermal safety and thermal stability of the propellant to some extent.