Gelatin is widely used in biomedical and pharmaceutical applications due to its biocompatibility, biodegradability, and tunable mechanical properties. However, its long-term mechanical stability is influenced by environmental factors such as temperature, humidity, and aging. This study investigates the viscoelastic behavior and long-term stability of gelatin using Time-Temperature Superposition (TTSP). Thermogravimetric Analysis (TGA) was employed to identify a temperature window free of moisture loss and thermal degradation, establishing an ideal range for conducting reliable TTSP measurements. Gelatin capsule samples were prepared in longitudinal and transversal orientations and tested using Dynamic Mechanical Analysis (DMA) frequency and temperature sweep experiments. The shift factors required for TTSP master curve construction were compared using the Williams-Landel-Ferry (WLF) and Arrhenius models. Additionally, Differential Scanning Calorimetry (DSC) was employed to assess the thermal transitions and phase stability of gelatin under different aging conditions. The results provide insights into gelatin mechanical behavior over time, highlighting the effects of molecular alignment, processing conditions, and thermal response to relaxation. This work demonstrates the applicability of TTSP in predicting the long-term thermo-mechanical behavior of gelatin-based biomaterials, facilitating the optimization of formulations for pharmaceutical and biomedical applications.
