高能固体推进剂粘合剂固化催化机理的密度泛函理论研究  

Density functional theory studies on the curing catalytic mechanisms of high energy solid propellant binder systems

作　　者：李慧[1] 罗国勤[2] 桑丽鹏[2] 朱卫华[1] LI Hui;LUO Guoqin;SANG Lipeng;ZHU Weihua(School of Chemistry and Chemical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China;Hubei Institute of Aerospace Chemical Technology,Xiangyang 441003,China)

机构地区：[1]南京理工大学化学与化工学院,南京210094 [2]湖北航天化学技术研究所,襄阳441003

出　　处：《固体火箭技术》2023年第1期96-101,共6页Journal of Solid Rocket Technology

摘　　要：为了探究固化催化剂三苯基铋(TPB)对固体推进剂粘合剂固化反应机理的影响,运用密度泛函理论(DFT)方法,系统地研究了粘合剂聚乙二醇(PEG)和缩水甘油叠氮聚醚(GAP)体系的固化反应:PEG/TDI、GAP/TDI、PEG/IPDI、GAP/IPDI、PEG/N-100和GAP/N-100。基于线性同步转变(LST)与二次同步转变(QST)方法相结合的LST/QST算法,搜索了基元反应路径的过渡态,确定反应的活化势垒。通过对比有无催化剂TPB两种情况下基元反应的活化能垒和过渡态结构的主要键长参数,结果表明,TPB对粘合剂体系的基元反应有着显著的影响。铋原子会靠近粘合剂端羟基O—H键,然后与O—H键的质子氢发生络合作用,导致羟基质子的反应活性增强。分离的H和O原子分别快速向异氰酸酯基团上的N和C原子移动并结合,从而大大降低了反应势垒,提高氨基甲酸酯结构的形成速率。In order to investigate the effects of catalyst triphenylbismuth(TPB)on the curing mechanism of solid propellant binders,density functional theory(DFT)was used to systematically study the common curing reactions of polyethylene glycol(PEG)and glycidyl azide polymer(GAP)binders:PEG/TDI,GAP/TDI,PEG/IPDI,GAP/IPDI,PEG/N-100,and GAP/N-100.Based on the complete LST/QST algorithm that combines the linear synchronous transit(LST)with the quadratic synchronous transit(QST)methods,the transition states of the elementary reaction paths were searched,and their activation barriers were determined.The activation energy barriers and main bond length parameters of the transition states in the elementary reaction were compared in the two cases with and without the catalyst TPB,the results demonstrate that TPB has a significant effect on the elementary reaction of the binder systems.The bismuth atom approaches the terminal hydroxyl O—H bond of the binders and then complexes with the proton hydrogen of the O—H bond,leading to the enhanced reactivity of the hydroxyl proton.The isolated H and O atoms rapidly move towards the N and C atoms on the isocyanate group and combine with them,so as to greatly lower the reaction barrier and increase the formation rate of the polyurethane structure.

关 键 词：固体推进剂粘合剂 固化剂 三苯基铋 固化基元反应 密度泛函理论 

分 类 号：V512[航空宇航科学与技术—航空宇航推进理论与工程]