PEG/增塑剂共混物相容性的分子动力学模拟和介观模拟  

Molecular Dynamic Simulations and Mesoscopic Dynamic Simulations on the Compatibility of PEG/PlasticizerBlends

作　　者：陈思彤 董可海 唐岩辉 裴立冠 王鑫 夏成 孔令泽 CHEN Si tong;DONG Ke hai;TANG Yan hui;PEI Li guan;WANG Xin;XIA Cheng;KONG Ling ze(College of Coast Defense Arm,Naval Aviation University,Yantai 264001,China;College of Aeronautics,Naval Aviation University,Yantai 264001,China)

机构地区：[1]海军航空大学岸防兵学院,山东烟台264001 [2]海军航空大学航空基础学院,山东烟台264001

出　　处：《含能材料》2020年第4期308-316,共9页Chinese Journal of Energetic Materials

摘　　要：为解决含能钝感增塑剂应用于硝酸酯增塑聚醚(NEPE)推进剂的问题,研究了增塑剂三羟甲基乙烷三硝酸酯(TMETN)、硝化甘油(NG)、1,2,4丁三醇三硝酸酯(BTTN)与粘合剂预聚物聚乙二醇(PEG)的相容性。采用分子动力学模拟计算了PEG、TMETN、NG、BTTN四种纯物质的溶度参数及分子内和分子间径向分布函数,得到相容性优劣顺序为:TMETN/PEG>BTTN/PEG>NG/PEG。BTTN分子中的亚甲基和TMETN的结构削弱了自身分子间作用、降低了与PEG溶度参数的差值;分析了共混物的结合能及分子间径向分布函数,认为增塑剂与PEG相容的本质为“分子间以非键作用相结合,范德华作用占主要比重”。此外,增塑剂与PEG分子的极性越相近、范德华作用的占比越大;通过介观模拟得到体系的介观形态演变过程,发现NG/PEG及BTTN/PEG易发生相分离、TMETN/PEG仅发生轻微的同相归并。最终得出:含能钝感增塑剂TMETN与PEG的相容性优于BTTN及NG,可以考虑将其代替或部分代替NG、降低NEPE推进剂的感度,为低易损战术武器的发展提供依据。In order to solve the problem of the application of energetic and insensitive plasticizers in Nitrate Ester Plasticized Poly ether(NEPE)propellants,the compatibilities of polymer binder PEG with Trimethylol ethane trinitrate(TMETN),1,2,4 butane triol trinitrate(BTTN)and nitroglycerin(NG)were studied.By simulating the solubility parameters(δ)of pure substances,the in ter and intra molecular radial distribution function,the order of compatibility was concluded as follows:TMETN/PEG>BTTN/PEG>NG/PEG.The methylene in BTTN and the structure of TMETN weakened the intermolecular interaction and reduced the difference ofδbetween plasticizer and PEG.The interaction of PEG/plasticizer was clarified by calculating binding energy and in ter molecular radial distribution function.Intermolecular interaction included Van der Waals and electrostatic interaction,in which the Van der Waals contributed the most.The better the compatibility between plasticizer and PEG,the greater the propor tion of the Van der Waals in the intermolecular interacion.The mesoscale morphologies of blends and the dynamic evolution process of the system were investigated by mesoscopic dynamic simulations.By analyzing isosurface of the density fields,order parameters and free energy density,it was found that phase separation occurred in NG/PEG,BTTN/PEG and slightly gathering oc curred in TMETN/PEG.Due to better compatibility with PEG,TMETN might be a potential plasticizer to replace or partially re place NG in NEPE.Present work provides reference for the development of low vulnerable tactical weapons.

关 键 词：聚乙二醇(PEG) 三羟甲基乙烷三硝酸酯(TMETN) 相容性 分子动力学模拟 介观动力学模拟 

分 类 号：TJ55[兵器科学与技术—军事化学与烟火技术] V512[航空宇航科学与技术—航空宇航推进理论与工程]