Mechanical loss coefficient (tan delta) values for polymers are dependent on temperature and frequency. What conditions were the MaterialUniverse values measured under?
The values quoted in MaterialUniverse are measured under ambient conditions (~20°C) and low frequencies (~1Hz). This value is provided to enable you to quickly compare the damping characteristics for all the main material classes.
If you require more in-depth information, then consider using one of the specialist polymer data tables, such as CAMPUS and M-Base Plastics. This data table contains values for dynamic shear modulus at different temperatures, gathered from manufacturers’ datasheets.