用小药量至爆时间试验研究炸药爆发分解反应动力学

用小药量至爆试验测定了10种炸药:单质炸药3-硝基-1,2,4-三唑-5-酮(NTO)及其铵盐(ANTO)、铅盐(PbNTO)、钾盐(KNTO)、乙二胺盐(ENTO)、混合炸药JO-6、JOB-9003、JP-1、JD-1、JH-16在不同温度下的爆发延滞期(t_(ind)).依据谢苗诺夫方程lnt_(ind,i)=(E_σ)/(RT_i),-lnA_,由lnt_(ind,i)对1/T_i的关系,用最小二乘法计算了爆发分解反应的表观活化能(E_α)、指前因子(A_σ)和1 000 s时的热爆炸临界温度(T_b).用非线性等转化率积分法所得的表观活化能(E_σ)校验了由lnt_(ind,i)~1/T_i关系得到的E_σ值.借助热力学关系式,计算了爆发分解反应的活化反应热力学参量活化自由能(ΔG~≠),活化焓(ΔH~≠)和活化熵(ΔS~≠].结果表明:(1) 以T_b和ΔG~≠作判据,知5种单质炸药和5种混合炸药的对热抵抗能力次序分别为:NTO＞ENTO＞ANTO＞KNTO＞PbNTO和JP-1＞JD-1＞JO-6＞JOB-9003＞JH-16;(2) E_α=E_α的事实佐证不同温度下爆发分解反应延滞期内分解深度相等,由此所得A_σ值可信,谢苗诺夫方程推导过程中A_σG(α)的假设合理.

Kinetic Study of the Explosive Decomposition Reaction of Small-scale Explosives Using the Time-to-explosion Experiment

The induction time(t_(ind)) prior to explosion of 10 explosives: 3-nitro-1,2,4-triazol-5-one(NTO), lead 3-nitro-1,2,4-triazol-5-onate(PbNTO), potassium 3-nitro-1,2,4-triazol-5-onate(KNTO), ethyenediamine 3-nitro-1,2,4-triazol-5-onate(ENTO),composite explosives ammonium 3-nitro-1,2,4-triazol-5-onate(ANTO),JO-6, JOB-9003, JP-1, JD-1 and JH-16 at different temperature was measured by the time-to-explosion experiments of small-scale explosives. Their values of apparent activation energy (E_σ) and pre-exponential constant(A_σ) of the explosive decomposition reaction and critical temperature of thermal explosion (T_b), i.e.the values of T corresponding to t_(ind)=1 000 s in Semenov′s equation were calculated from the relationship of lnt_(int) vs. 1/T_i by the linear least-squares method. The values of E_α obtained by integral isoconversional non-linear method were used to check the values of E_σ obtained by the linear-squares method. With the help of thermodynamic formulae, the thermodynamic parameters free energy of activation (ΔG~≠), enthalpy of activation (ΔH~≠) and entropy of activation (ΔS~≠)] of activation for the explosive decomposition reaction were calculated. The results show that (1) the heat-resistance ability of five single-compound explosives and five composite explosives using ΔG~≠ and T_b as criteria decreases in the order NTO＞ENTO＞ANTO＞KNTO＞PbNTO and JP-1＞JD-1＞JO-6＞JOB-9003＞JH-6. (2) The fact of E_α=E_σ indicates that the value of A_σ obtained and assumption of adopting A_σ>>G(α) in derivation of Semenov′s formula are tenable.