Space endeavours heavily rely on materials with outstanding properties, which must be maintained during the whole mission and beyond. Materials used within habitable pressurized space environments are subjected to several sources of degradation, including heat, time, static and dynamic loads, and humidity. An understanding of the physical changes that cause the decay of the materials performance over time is crucial to predict their performance and durability. To ensure a safe working life, in particular in the context of future long-term space missions, it is critical to study how systems perform, degrade, and fail over time, allowing the design of systems that work better and last longer.

In this study, the lifetime of polymers and elastomers is studied through accelerated tests, determining for how long the material's mechanical properties will be maintained over time. With this aim, a dynamic mechanical analysis (DMA) may be performed on multiple materials (e.g. Elastomers, PMMA, PEI). In this test, tensile static and dynamic loads are applied to the sample, while the mechanical and viscoelastic properties are monitored. A frequency sweep is performed for each selected temperature over a wide range, and the resulting data is overlaid to build a master curve. The projection of the material behaviour over time can be performed using the time-temperature superposition principle, enabling the prediction of the material's viscoelastic behaviour up to 15 years of lifetime.

Moreover, the effect of environmental factors on the polymers structure and stability is also studied. In particular, the DMA test is performed varying the surrounding relative humidity, in order to evaluate its impact on the mechanical performance. Overall, this study contributes to the development of durable materials tailored for prolonged space mission, ensuring that the mechanical performance will be maintained throughout the operational life.