TKX-55在常压与高压下的热分解特性

Thermal Decomposition Characteristics of TKX-55 Under Normal Pressure and High Pressure

采用差示扫描量热法(DSC)和热重分析法(TG)研究了5,5'-双(2,4,6-三硝基苯基)-2,2'-双(1,3,4-噁二唑)(TKX-55)常压(0.1 MPa)和5.0 MPa高压下的热分解性能,采用Kissinger和Ozawa方法计算了常压下TKX-55的热分解动力学参数,并与六硝基茋(HNS)对比,以研究分子结构及其性能的相关性。结果表明,高压下TKX-55的热分解行为与常压状态下相比,峰形更加尖锐,在5.0 MPa高压环境下TKX-55仍然保持较高的热稳定性,初始分解温度为355.69℃,比HNS初始分解温高约35℃。随着升温速率的增加,TKX-55及HNS的分解峰温均向高温方向偏移,而在不同升温速率下TKX-55的分解峰温均明显高于HNS。非线性等转化率积分法计算获得TKX-55的分解活化能为233.71 kJ·mol^(-1),HNS为197.87 kJ·mol^(-1),TKX-55的分解活化能明显高于HNS,表明TKX-55较HNS具有更加优异的热稳定性。

The thermal decomposition properties of 5,5'-bis(2,4,6-trinitrophenyl)-2,2'-bi(1,3,4-oxadiazole)(TKX-55)at nor-mal pressure(0.1 MPa)and high pressure(5.0 MPa)were studied by differential scanning calorimetry(DSC)and thermogravi-metric analusis(TG).The thermal decomposition kinetic parameters of TKX-55 at normal pressure were calculated by Kissing-er's method and Ozawa's method and compared with those of hexanitrostilbene(HNS)to study the correlation between molec-ular structure and its properties.Results show that compared with normal pressure state,the shape of exothermal peak of thermal decomposition behavior of TKX-55 under high pressure is sharper.Under the high pressure environment(5.0 MPa),TKX-55 still maintains high thermal stability.The initial decomposition temperature is 355.69℃,which is about 35℃higher than the initial decomposition temperature of HNS.With increasing the heating rate,the decomposition peak temperature of TKX-55 and HNS is shifted to high temperature,and the decomposition peak temperature of TKX-55 at different heating rates is obviously higher than that of HNS.The decomposition.activation energy of TKX-55 obtained by integral isoconversional non-linear method(NL-INT method)is 233.71 kJ·mol^-1 and the decomposition.activation energy of HNS is 197.87 kJ·mol^-1.The decomposition ac-tivation energy of TKX-55 is obviously higher than HNS,indicating that TKX-55 has more excellent thermal stability than HNS.