Posted by This study investigates the spectral and PXR diffraction characterization of SBECD, its thermal stability profile, and decomposition mechanism using isoconversional methods. Since the simple ASTM E698 method does not provide realistic data, the Flynn–Wall–Ozawa, Friedman, and NPK methods were employed, leading to the kinetic triplet that characterizes the oxidative thermolysis of this compound.
Thermoanalytical curves TG (thermogravimetric/mass curve), DTG (derived thermogravimetric/mass derivative), and HF (heat flow curve) in a dynamic air atmosphere were recorded at five different heating rates in non-isothermal conditions, revealing a good thermal stability of this analyte in an anhydrous state of up to ~240 °C, after losing the water content (~8%) in the 40–140 °C temperature range. The main decomposition process of the in situ formed anhydrous SBECD was investigated by kinetic analysis, initially by the employment of the ASTM E698 method, followed by two traditional isoconversional methods (FR and FWO), and later the kinetic triplet was determined using the NPK method.
The non-parametric kinetic method (NPK) suggested that SBECD is degraded by the contribution of two processes, both containing chemical degradations and physical transformations.
The analysis of the reaction rate curves reveal two separate processes that concur at the decomposition of anhydrous SBECD, when the thermal treatment is carried out at low heating rates (≤4 °C·min−1). At higher heating rates, due to thermal inertia, the processes are no longer separated or a change in the decomposition mechanism takes place.
Ledeți, I.; Temereancă, C.; Ridichie, A.; Ledeți, A.; Ivan, D.L.; Vlase, G.; Vlase, T.; Tomoroga, C.; Sbârcea, L.; Suciu, O. Oxidative Thermolysis of Sulfobutyl-Ether-Beta-Cyclodextrin Sodium Salt: A Kinetic Study. Appl. Sci. 2025, 15, 441. https://doi.org/10.3390/app15010441