添加剂对二硝酰胺铵热分解行为的影响

Influences of Additives on Thermal Decomposition Behavior of Ammonium Dinitramide

向二硝酰胺铵(ADN)样品中加入3种添加剂3-氨基-2-萘酚、尿素和乌洛托品(HMT),制备了球形化改性ADN及ADN/添加剂混合物;利用差示扫描量热法(DSC)和热重(TG)分析法研究了3种添加剂对ADN热分解行为的影响;采用Kissinger法和Ozawa法计算了其活化能;利用等温方法(TG法和TAM法)进一步研究了纯ADN和ADN/HMT在等温条件下的热分解行为。结果表明,3种添加剂均提高了ADN的起始分解温度和峰温;当添加HMT时,热分解起始温度和峰温提高最为明显,起始温度分别提高7.3～10.0℃(DSC)和6.3～7.1℃(TG);分解峰温提高7.0～9.0℃(DSC);Kissinger法和Ozawa法计算得到ADN/HMT热分解的活化能分别为155.6和165.2kJ/mol;添加HMT后,ADN的初始分解速率由3.0%/h降至1.6%/h,ADN的放热峰由单峰变为肩峰,且出峰位置明显延后,表明HMT能明显抑制ADN的热失重和放热行为。

Prilled and modified ammonium dinitramide(ADN)and ADN/additive mixtures were prepared by adding three kinds of additives 3-amino-2-naphthol,urea and urotropine(hexamethylenetetramine,HMT)into ADN.The effect of the three kinds of additives on thermal decomposition behaviors of ADN was studied by differential scanning calorimetry(DSC)and thermogravimetric(TG)analysis method.The activation energies were calculated by Kissinger′s method and Ozawa′s method.The thermal decomposition behaviors of pure ADN and ADN/HMT mixture under isothermal conditions were further studied by isothermal methods(TG method and TAM method).The results show that the onset temperature and peak temperature of ADN decomposition were all increased by adding the three kinds of additives.When HMT was added to ADN,the enhancement of the onset temperature and the peak temperature of ADN decomposition is the largest among the three kinds of additives,the onset temperature of ADN is increased by 7.3-10.0℃from DSC and 6.3-7.1℃from TG,and the peak temperature is increased by 7.0-9.0℃from DSC.The activation energies of ADN/HMT calculated by Kissinger′s method and Ozawa′s method are 155.6 and 165.2 kJ/mol,respectively.When HMT is added,the initial decomposition rate of ADN is decreased from 3.0%/h to 1.6%/h,the exothermic peak changes from single peak to shoulder peak,and the peak position is obviously delayed,indicating that HMT can significantly inhibit the thermal mass loss and exothermal behavior of ADN.