分子动力学及热分析方法研究CL-20与推进剂主要组分的相互作用

摘要

采用分子动力学模拟(MD)计算与差示扫描量热法(DSC)相结合,研究六硝基六氮杂异伍兹烷(CL-20)与推进剂主要组分间的相互作用,用理论键长变化趋势分析实验结果.分子动力学模拟计算键长变化趋势结果表明,CL-20与黑索今(RDX)、奥克托今(HMX)混合体系的引发键N-NO2键最大键长Lmax随温度升高显著的单调递增,且当CL-20与RDX、HMX共混后,键长普遍增大,更容易断裂分解;而CL-20与硝化棉(NC)、硝化甘油(NG)共混后各个键长均与单质状态下存在时的键长相比变化不大,一些键长均小于其单质状态下存在时的键长,推测CL-20与NG、NC键混合后稳定性较好,不易发生键的断裂分解.DSC结果表明,CL-20与RDX和HMX之间在大于156 ℃的较高温度条件下存在强烈的相互作用,CL-20与NG、NC之间没有明显的化学作用.%The interactions between hexanitrohexaazaisowurtzitane (CL-20) and other solid propellant components has been studied by using molecular dynamics simulations (MD) and differential scanning calorimetry (DSC).The experimental results were analyzed in comparison to the theoretical bond length variation tendency.It has been indicated by the MD calculation results that the maximum bond lengths (Lmax) of the N-NO2 trigger bond were increased monotonously with the elevated temperature for both pristine CL-20 and RDX/HMX mixture.Besides,longer bond lengths have been observed when CL-20 was mixed with RDX and HMX,suggesting an easier decomposition reaction.However,little change of the bond lengths occurred when CL-20 was mixed with NG/NC,and more importantly,several bonds became shorter.It could be inferred better stability of CL-20 when it was mixed with NG/NC,and it was more difficult to decompose.It's indicated from the DSC results that there were strong interactions between CL-20 and both RDX and HMX,when the temperature was higher than 156 ℃.There were no obvious interactions between CL-20 with NG/NC.