NEPE推进剂中硝酸酯扩散的分子动力学模拟及实验研究  

Molecular Dynamics Simulation and Experimental Study on Migration of Nitric Ester in NEPE Propellant

作　　者：屈蓓[1] 潘清[1] 唐秋凡 齐晓飞[1] 蔚红建[1] 李吉祯[1] QU Bei;PAN Qing;TANG Qiu-fan;QI Xiao-fei;YU Hong-jian;LI Ji-zhen(Xi′an Modern Chemistry Research Institute,Xi′an 710065,China)

机构地区：[1]西安近代化学研究所,陕西西安710065

出　　处：《火炸药学报》2018年第3期278-284,共7页Chinese Journal of Explosives & Propellants

基　　金：国家自然科学基金(No.21401124)

摘　　要：针对硝酸酯增塑聚醚(NEPE)推进剂中硝酸酯迁移扩散影响装药服役寿命的问题,采用分子动力学模拟与液相色谱实验相结合,开展硝酸酯(NG/BTTN)在NEPE推进剂中扩散机理及扩散系数的理论计算研究,并探讨了温度对NG和BTTN在NEPE推进剂中扩散行为的影响。结果表明,NG/PEG体系中NG分子的空间位置对初始位置的偏离程度相比于BTTN/PEG体系中BTTN分子较大,且BTTN分子在两个温度条件下的扩散系数均小于NG分子;实验计算的NG和BTTN在55℃和65℃下扩散系数的数量级与分子动力学模拟计算结果相同,通过模拟计算得到两种温度下NG分子在共混体系中的扩散系数分别为3.42×10-13 m2/s(65℃)和4.81×10-14 m2/s(55℃),BTTN分子在共混体系中的扩散系数分别为2.93×10-13 m2/s(65℃)和4.25×10-14 m2/s(55℃);随温度升高,硝酸酯分子的扩散系数增大,即迁移性增大,这与分子动力学模拟结果一致。Aiming at the problem affecting the service life of charge due to the migration and diffusion of nitric ester in nitric ester plasticized polyether （NEPE） propellants, the theoretical calculation of diffusion mechanism and diffusion coefficient of nitric ester （NG/BTTN） in NEPE propellants was carried out through the combination of molecular dynamics （MD） simulation and high performance liquid chromatography （HPLC） experiment. The influence of temperature on the diffusion behavior of NG and BTTN in NEPE propellant was explored. The results indicate that the spatial position of NG molecules in NG/PEG system which deviates from initial position is larger than that of BTTN molecules in BTTN/PEG system. In addition, the diffusion coefficients of BTTN molecules are less than that of NG molecules under two temperature conditions. The order of magnitude of diffusion coefficients of NG and BTTN at 65℃ and 55℃ calculated by experiment are the same with the results calculated by the MD simulation. The diffusion coefficients of NG molecules in the blends obtained by simulation calculation is 3.42×10^-13m^2/s at 65℃and 4.81×10^-14m^2/s at 55℃. The diffusion coefficients of BTTN molecules in the system is 2.93×10 -13 m 2/s at 65℃and 4.25×10 -14 m 2/s at 55℃. With increasing the temperature, the diffusion coefficients of nitric ester molecules increase, that is, the migration increases, which is consistent with the results of MD simulation.

关 键 词：硝酸酯增塑聚醚推进剂 NEPE推进剂 硝酸酯 扩散系数 分子动力学模拟 

分 类 号：TJ55[兵器科学与技术—军事化学与烟火技术] O641[理学—物理化学]