动态真空安定性方法评估LA和CMC-LA热安定性

Evaluation of the Thermal Stability of LA and CMC-LA by Dynamic Vacuum Stability Test Method

采用动态真空安定性（DVST）方法研究了叠氮化铅（LA）和羧甲基纤维素叠氮化铅（CMC-LA）的热分解过程。利用微分法分析了测试数据。获得了LA和CMC-LA的反应机理函数和表观活化能,剖析了羧甲基纤维素钠晶型控制剂对LA安定性和热分解反应动力学参数的影响。结果表明,在非等温阶段,60~100℃,LA热分解反应的机理函数为Zhuralev-Lesokin-Tempelman方程,表观活化能（Ea）分别是86.53、42.26、39.43、38.09 k J·mol-1和10.84k J＂mol-1。在60~70℃,CMC-LA热分解反应的机理函数为Avrami-Erofeev方程,Ea分别是133.02 k J·mol-1和41.87 k J·mol-1,在80~100℃,CMC-LA热分解反应的机理为减速型α-t曲线,Ea分别是43.07、34.34 k J·mol-1和33.46 k J·mol-1。添加羧甲基纤维素钠改变了LA的反应机理函数,使得CMC-LA在60~70℃产气量更小,热安定性更好。

The thermal decomposition process of lead azide（ LA） and carboxymethylcellulose lead azide（ CMC-LA） was studied by dynamic vacuum stability test（ DVST） method. The test data were analyzed by differential method. The reaction mechanism function and apparent activation energy of CMC-LA and LA were obtained. The influence rule of sodium carboxymethyl cellulose crystal control agent on the stability and kinetic parameters of the thermal decomposition reaction of LA was analyzed. Results show that in the non-isothermal stage,the mechanism function of the thermal decomposition reaction of LA in the temperature range from 60 ℃ to 100 ℃ is the Zhuralev-Lesokin-Tempelman equation,the apparent activation energy（ Ea） is 86. 53,42. 26,39. 43,38. 09 k J·mol-1and 10. 84 k J·mol-1,while thermal decomposition mechanism function of CMC-LA in the temperature range from 60 ℃ to 70 ℃ is the Avrami-Erofeev equation with Eaof 133. 02 k J·mol-1and 41. 87 k J·mol-1and thermal decomposition reaction mechanism of CMC-LA in the temperature range from 80 ℃ to 100 ℃ is the deceleration type α-t curve with Eaof 43. 07,34. 34 k J·mol-1and 33. 46 k J·mol-1. Addding sodium carboxymethylcellulose changes the reaction mechanism function of LA,leading the gas production of CMC-LA smaller at 60 ℃ to 70 ℃,and with a better thermal stability.