Polyimides examples of half-life versus temperature

The results are correctly simulated by an Arrhenius law with predicted 25 000-hour-serv-ice temperatures between approximately 165°C and 235°C. 

NASA is developing a special polyimide (PETI-5) for the High Speed Civil Transport (Mach 2.4) whose lifespan is more than 60 000 hours at 177°C with excellent property retention at this temperature. 

The behaviour of polyimides is generally also good at low temperatures, allowing use from -60°C down to -250°C, according to the grades and the stresses. 

As films, certain polyimides remain functional at cryogenic temperatures, -269°C for example. Typical glass transition temperatures for polyimides are 300°C and above. 

These results relate to some grades only and cannot be generalized. 

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Figure 4.118. Polyimides examples of half-life versus temperature...

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