In this reported study, the density functional theory (DFT) was used at the (U)B3LYP/6-311G(d,p) level to investigate the stabilization process of the nitrate ester plasticized polyether propellant (NEPE). Molecular simulations were conducted of the reaction that generates NO₂, the autocatalytic and aging reaction triggered by the NO₂, and the nitrogen dioxide absorption reaction of the stabilizers during the propellent stabilization process. These simulations were derived using the transition-state theory (TST) and variational transition-state theory (VTST). The simulation results suggested that the stabilization of the NEPE propellant consisted of three stages. First, heat and NO₂ were generated during the denitrification reaction of nitroglycerine (NG) and 1,2,4-butanetriol trinitrate(BTTN) in the NEPE propellant. Second, nitroso products were generated by the reactions of N-Methyl-4-nitroaniline (MNA) and 2-nitrodiphenylamine (2NDPA) with NO₂. Third, the stabilizers were exhausted and the autocatalytic reaction of NG and BTTN and the aging reaction of polyethylene glycol (PEG) were triggered by the heat and NO₂ generated in the first stage. By comparing the energy barriers of the various reactions, it was found that the NO₂ generated from the denitrification reaction significantly reduced the reaction energy barrier to 105.56–126.32 kJ/mol, also increased the reaction rate constant, and decreased the thermal stability and energetic properties of the NEPE propellant. In addition, the NO₂ also weakened the mechanical properties of the NEPE propellant by attacking the –CH₂ groups and the O atoms in the PEG molecular chain. The energy barriers of the reactions of MNA and 2NDPA with NO₂ (94.61–133.61 kJ/mol) were lower than those of the autocatalytic and decomposition reactions of NG, BTTN, and the aging reactions of PEG (160.30–279.46 kJ/mol). This indicated that, by eliminating NO₂, the stabilizer in the NEPE propellant can effectively prevent NO₂ from reacting with the NG, BTTN, and PEG in the NEPE propellant. Consequently, this would help maintain the energy and mechanical properties of the NEPE propellant, thereby improving its thermal stability.

在本报告的研究中，在(U)B3LYP/6-311G(d,p)水平上使用密度泛函理论(DFT)来研究硝酸酯增塑聚醚推进剂(NEPE)的稳定过程。对推进剂稳定过程中产生NO _{2 的}反应、NO ₂引发的自催化和老化反应以及稳定剂的二氧化氮吸收反应进行了分子模拟。这些模拟是使用过渡态理论 (TST) 和变分过渡态理论 (VTST) 得出的。模拟结果表明NEPE推进剂的稳定化由三个阶段组成。一、热量和NO ₂硝化甘油（NG）和1,2,4-丁三醇三硝酸酯（BTTN）在NEPE推进剂中发生反硝化反应时产生。_{其次，N-甲基-4-硝基苯胺(MNA)和2-硝基二苯胺(2NDPA)与NO 2}反应生成亚硝基产物。第三，第一阶段产生的热量和NO ₂导致稳定剂耗尽，引发NG和BTTN的自催化反应以及聚乙二醇(PEG)的老化反应。通过比较各反应的能垒，发现NO ₂反硝化反应产生的反应能垒显着降低至105.56-126.32 kJ/mol，同时增加了反应速率常数，并降低了NEPE推进剂的热稳定性和能量特性。此外，NO ₂还通过攻击PEG分子链中的-CH ₂基团和O原子，削弱了NEPE推进剂的机械性能。_{MNA和2NDPA与NO 2}反应的能垒(94.61~133.61 kJ/mol)低于NG、BTTN的自催化和分解反应以及PEG的老化反应(160.30~279.46 kJ/mol)。 。这表明，NEPE推进剂中的稳定剂通过消除NO _{2 ，​​可以有效防止NO2}与 NEPE 推进剂中的 NG、BTTN 和 PEG 发生反应。因此，这将有助于保持 NEPE 推进剂的能量和机械性能，从而提高其热稳定性。