Abstract The thermal properties of bulk and nanoconfined HMX were studied using differential scanning calorimetry in dynamic scanning mode at rates ranging from 0.3 to 100 °C/min. At the slowest heating rates, decomposition occurs in the solid phase; at intermediate heating rates, it starts in the solid phase, melts, and finishes with a faster rate of reaction in the liquid state; and at the highest heating rates, the decomposition is entirely in the liquid phase. The activation energy decreases with conversion and is highest for 12 nm-diameter pores. The decomposition reaction is accelerated for nanoconfined HMX compared to the bulk with the onset of decomposition decreased by 1–5 °C in 50 nm-diameter pores and by 4–11 °C in 12 nm-diameter pores. The kinetics of decomposition is well described by a first-order autocatalytic reaction model with the reaction rate constants increasing with nanoconfinement. In addition, the reaction rate constant is one order of magnitude higher in the melt state than in the solid state.

中文翻译：

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纳米限制下固态和液态 HMX 的分解

摘要 使用差示扫描量热法在动态扫描模式下以 0.3 至 100 °C/min 的速率研究了块体和纳米限制 HMX 的热性能。在最慢的加热速率下，固相发生分解；在中等加热速率下，它从固相开始，熔化，并以更快的液态反应速率结束；在最高加热速率下，分解完全在液相中。活化能随着转化而降低，并且在 12 nm 直径的孔中最高。与本体相比，纳米限制的 HMX 的分解反应加速，在 50 nm 直径的孔中分解开始降低 1-5°C，在 12 nm 直径孔中降低 4-11°C。一阶自催化反应模型很好地描述了分解动力学，反应速率常数随着纳米限制而增加。此外，熔融态的反应速率常数比固态高一个数量级。