Liu Kun, Cheng Xinlu
Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.
Polymers (Basel). 2025 May 27;17(11):1492. doi: 10.3390/polym17111492.
Poly(3,3-bis(azidomethyl)oxetane(BAMO)-tetrahydrofuran(THF)) copolymer (PBT) and ammonium perchlorate (AP) are critical components of solid rocket propellants, where their interfacial bonding mechanisms and temperature-dependent mechanical properties are pivotal to propellant reliability. In this study, density functional theory (DFT) calculations were employed to evaluate the adsorption energies between common AP crystal surfaces and PBT units, identifying the most energetically favorable adsorption configurations. The atomic configurations and charge transfer characteristics at the PBT-AP interface were systematically analyzed. Molecular dynamics (MD) simulations were further conducted to determine the thermally stable operating range of the PBT-AP system. The results reveal a strong temperature dependence of mechanical performance, with viscous failure mechanisms and damage thresholds during static tensile processes investigated across varying temperatures. Notably, mechanical properties remain stable below 60 °C but deteriorate significantly above this temperature. This study elucidates the influence of a PBT-AP interfacial microstructure and temperature on mechanical performance and tensile fracture damage boundaries, providing crucial insights for the design, formulation, and safe application of PBT-based solid rocket propellants.
聚（3,3 - 双（叠氮甲基）氧杂环丁烷（BAMO）- 四氢呋喃（THF））共聚物（PBT）和高氯酸铵（AP）是固体火箭推进剂的关键成分，它们的界面结合机制和温度依赖性力学性能对推进剂的可靠性至关重要。在本研究中，采用密度泛函理论（DFT）计算来评估常见AP晶体表面与PBT单元之间的吸附能，确定能量上最有利的吸附构型。系统地分析了PBT - AP界面处的原子构型和电荷转移特性。进一步进行分子动力学（MD）模拟以确定PBT - AP系统的热稳定工作范围。结果表明力学性能对温度有强烈依赖性，研究了不同温度下静态拉伸过程中的粘性失效机制和损伤阈值。值得注意的是，力学性能在60°C以下保持稳定，但在此温度以上会显著恶化。本研究阐明了PBT - AP界面微观结构和温度对力学性能及拉伸断裂损伤边界的影响，为基于PBT的固体火箭推进剂的设计、配方和安全应用提供了关键见解。
