Pressure Sensing and Multi-Resolution Kinetic Modeling of Oxygen-Releasing Compounds

Reliable monitoring of gas-releasing reactions is essential for emerging pressure-driven actuation and soft robotic systems. However, real-time sensing is required to analyze the gas release trends and to consistently monitor the reaction kinetics. This work presents a compact pressure-sensing approach to investigate the oxygen release kinetics from the decomposition of anthracene-endoperoxide (ANT-EPO) molecules in an aqueous environment. A sealed setup with a pressure sensor was used to capture the gradual pressure increase resulting from oxygen evolution at room temperature. To extract meaningful kinetic information, a multi-step signal processing pipeline was applied, including baseline offset correction, Savitzky-Golay (SG) smoothing to reduce highfrequency noise, and discrete wavelet transform (DWT) filtering to isolate the reaction-induced pressure trend from the drift. Temperature effects were taken into consideration to account for ambient effects on pressure fluctuation. The processed denoised pressure-time profile revealed distinct kinetic phases and was fitted using both first-order and logistic models. The resulting pressure profile exhibited a sigmoidal form that was described more accurately by a logistic model (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{R}^{2}=0.967$</tex>, RMSE <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$=0.19 \text{kPa}$</tex>, AIC <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$=-2.91 \mathrm{e}+06$</tex>) than by a first-order exponential (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$R^{2}=0.929$</tex>). The proposed approach provides a foundation for characterizing slow gas-releasing reactions and supports the development of chemical actuation platforms that rely on controlled gas generation.