發射藥安定劑作用機理及效用評估之理論計算研究

Theoretical Study on the Stabilizing Mechanisms between Propellants and Stabilizers

劉敏憲(Min-Hsien Liu) ； 鄭根發(Ken-Fa Cheng) ； 吳明勇(Ming-Yung Wu)

《化學》 71卷4期 (2013/12) Pp. 347-359

https://doi.org/10.6623/chem.2013033

摘要

本文選擇傳統安定劑-二苯胺(DPA)、乙基中定劑(EC)、N-甲基-4-硝基苯胺(MNA)及新式安定劑-硝基取代之N,N' -二苯基丙二醯胺安定劑(M3-M5)等六種發射藥安定劑，運用理論計算模擬，採用Gaussian 09 程式軟體中與電子相關之密度函數理論(DFT) B3LYP/6-31G (d, p)的計算方法，以獲取安定劑分子能階比較反應性之強弱，並透過安定劑與硝基自由基反應作用之過渡態程序模擬，利用獲得之熱力學熱焓(Enthalpy, H)進行化學動力學的能障分析，另藉由過渡態理論估算反應有關的反應速率常數(k)及指數前因子(A)，以輔助判斷安定劑之安定效果。

關鍵字

安定劑 ； 發射藥 ； 密度泛函數理論(DFT) ； 能障

並列摘要

Six kinds of propellant stabilizers, including diphenylamine (DPA), enthyl centralite (EC), N-methyl-4-nitroaniline (MNA), N,N'-dipheny-malonyl amine (M3~M5) were studied theoretically heren. By using the Gaussian 09 program, electron correlated density function theory (DFT) B3LYP/6-31G (d, p) computation method has been adopted to obtain corresponding energy difference between energy levels of the highest occuopied molecular oorientational HOMO and the lowest unoccupied molecular oorientational LUMO, upon considering to compare stabilizers reactivity. Furthermore, the composite reaction system of stabilizer and nitrogen dioxide radical was simulated through synchronous Transition-Guided Quasi-Newton (STQN) and was assigned QST3 procedure to search the transition state complex. The kinetic analysis of reaction energy barrier, along with the reaction rate constant (k) and the preexponential factor (A) evalued from the transition state theory, we can auxiliarily judge the stabilizing effect of each stabilizer.

並列關鍵字

Stabilizer ； Propellants ； Density functional theory (DFT) ； Energy barrier