Kinetic Modeling and Quantification of Pressure-Derived Oxygen Accumulation from Anthracene Endoperoxides under Confined Conditions.

The controlled release of gas is central to chemically triggered systems and pressure-driven processes, where both the magnitude and temporal evolution of gas must be predictable. Anthracene-endoperoxides (ANT-EPO) are a class of oxygen-releasing molecules that decompose with well-defined stoichiometry and temperature-dependent kinetics, making them attractive candidates for tunable chemical sources. Prior work has demonstrated optical and pressure-based monitoring of ANT-EPO decomposition, providing valuable insights into its oxygen release behavior. The present work establishes a kinetic model to quantify and estimate oxygen release from ANT-EPO under confined geometries, using pressure as an experimental observable. Pressure-time data acquired using gauge and absolute sensors at ambient room temperature and 37 °C were converted into gas-phase oxygen accumulation using an ideal gas law formulation. The resulting profiles were described by first-order kinetics, yielding temperature-dependent rate constants that were independent of concentration. An apparent gas-phase recovery factor was introduced to account for nonideal conversion between the theoretical oxygen release capacity and the experimentally accessible oxygen amount recovered in the headspace. These parameters were integrated into a compact empirical-mechanistic model that relates concentration and temperature to pressure evolution within the defined chamber geometry. Model performance was evaluated through forward prediction of oxygen release using an independently measured concentration excluded from parameter extraction, demonstrating accurate prediction without refitting. This approach enables quantitative analysis and prediction of confined gas-evolving reactions and provides a basis for translating ANT-EPO reaction kinetics into pressure evolution under defined operating conditions. This work bridges responsive materials, chemical kinetics, and engineering applications, demonstrating ANT-EPO as a potential controllable oxygen source.