ISBN 978-3-8439-5718-2

978-3-8439-5718-2, Reihe Thermodynamik

Jana Kerkhoff
Controlling Quality and Kinetics of Drying Processes for Amorphous Solid Dispersions

144 Seiten, Dissertation Technische Universität Dortmund (2025), Softcover, A5

Zusammenfassung / Abstract

The present thesis investigates the drying of amorphous solid dispersions (ASDs) composed of PVPVA64 and indomethacin from ethanol–water solutions. Thermodynamic modeling based on the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) was employed to identify suitable feed compositions that remain homogeneous throughout the entire drying process.

Furthermore, a novel modeling approach was developed to describe the drying kinetics of ASD solutions. Based on single-solvent drying data of the pure polymer, the model enables reliable prediction of drying kinetics in mixed-solvent systems, showing very good agreement with experimental results.

Following primary drying, the removal of residual solvent during secondary drying represents a significant challenge due to strongly hindered diffusion in glassy ASDs. To enhance secondary drying, a water-assisted drying strategy at constant relative humidity was investigated. Using the non-equilibrium extension of PC-SAFT, both the compositional evolution during secondary drying and the optimal relative humidity for efficient ethanol removal were predicted and experimentally validated.