NEPE推进剂/衬层界面固化反应机理的理论研究  

Theory study of curing reactions at NEPE propellant/liner adhesive interface

作　　者：桑丽鹏 李慧[3] 闵辉海[2] 刘晨 朱卫华 SANG Lipeng;LI Hui;MIN Huihai;LUI Chen;ZHU Weihua(National Key Laboratory of Aerospace Chemical Power,Xiangyang441003,China;Hubei Institute of Aerospace Chemical Technology,Xiangyang441003,China;School of Chemistry and Chemical Engineering,Nanjing University of Science and Technology,Nanjing210094,China)

机构地区：[1]航天化学能源全国重点实验室,襄阳441003 [2]湖北航天化学技术研究所,襄阳441003 [3]南京理工大学化学与化工学院,南京210094

出　　处：《固体火箭技术》2024年第4期493-500,共8页Journal of Solid Rocket Technology

基　　金：国家自然基金项目(22175059)。

摘　　要：推进剂/衬层界面是固体火箭发动机燃烧室中的关键结构。采用密度泛函理论(DFT)研究了硝酸酯增塑聚醚(NEPE)推进剂/衬层粘合界面的反应机理,评估了界面结构中不同组分之间的反应途径和过渡态结构,包括聚乙二醇(PEG)、甘油(GO)、三乙醇胺(TEA)、N,N,N′,N′-四(2-羟乙基)乙二胺(THEED)、甲苯二异氰酸酯(TDI)、异佛尔酮二氰酸酯(IPDI)和多官能度异氰酸酯(N-100);得到不同组分间反应路径的吉布斯自由能曲线。结果表明,TDI与PEG、GO、TEA和THEED之间的反应竞争性发生在第二步修饰反应,即第二个—NCO基团与端羟基的氢转移反应生成产物——聚氨酯;含羟基化合物中端羟基的增多有利于与2,4-TDI反应,但对2,6-TDI体系影响不大。此外,对比相关基元反应决速步的反应速率常数可知,2,4-TDI体系的反应速率常数大多高于2,6-TDI体系、IPDI体系和N-100体系,基元反应PEG+INT1较易发生,而基团反应N-100/THEED最慢发生。The propellant/liner interface is a critical structure in the combustion chamber of solid rocket motors.Herein,the re⁃action mechanism of the nitrate ester plasticized polyether(NEPE)propellant/liner interface was investigated using density function⁃al theory(DFT),and the reaction pathways and transition state structures between different components in the interfacial structure were evaluated,including polyethylene glycol(PEG),glycerol(GO),triethanolamine(TEA),N,N,N′,N′⁃tetra(2⁃hydroxyethyl)eth⁃ylenediamine(THEED),toluene diisocyanate(TDI),isophorone diisocyanate(IPDI)and polyisocyanate desmodur(N⁃100).The Gibbs free energy curves of reaction paths between the different components were obtained.The results show that the competitive re⁃action between TDI and PEG,GO,TEA or THEED occurs in the second step of the modification reaction,i.e.,the hydrogen transfer reaction between the second—NCO group and the terminal hydroxyl group produces the product,namely polyurethane.The increase of terminal hydroxyl groups in the hydroxyl compounds favors the reaction with 2,4⁃TDI and has little effect on the 2,6⁃TDI system.In addition,a comparison of the reaction rate constants of the relevant elementary reaction rate⁃determining steps shows that the reac⁃tion rate constants of the 2,4⁃TDI system were mostly higher than the 2,6⁃TDI system,the IPDI system and the N⁃100 system.The elementary reaction PEG+INT1 occurs more readily,whereas the elementary reaction N⁃100/THEED occurs most slowly.

关 键 词：NEPE固体推进剂 衬层 界面结构 密度泛函理论 基元反应 

分 类 号：V512[航空宇航科学与技术—航空宇航推进理论与工程]