Molecular mobility in Soluplus, a polymer with extremely low dynamic fragility; A study by thermally stimulated depolarization currents

•TSDC confirms the low Tg and the extremely low dynamic fragility of Soluplus®.•The relaxation map reveals the large dispersion of MW and the low dynamic fragility.•The aging tests on Soluplus® do not change the kinetics of the main relaxation.•The molecular mobility found clarifies the use as a carrier for poorly soluble drugs. This is a thermostimulated depolarization currents (TSDC) study of the slow molecular mobility in Soluplus®, an amorphous polymer used in the production of amorphous solid dispersions for pharmaceutical purposes. We carried out this study due to the importance of these applications and the very specific characteristics of this polymer, namely an extremely low dynamic fragility. TSDC proved to be a suitable technique to clarify the nature of slow molecular mobility in Soluplus® and understand the suitability of this glass former for applications.