A Study of FEP Behaviour in the Space Environment

Teflon® FEP is regularly used as thermal control film in space applications with thicknesses varying between 12.5 μm (1/2 mil) and 127 μm (5 mil).

Both flight and ground simulation data indicate a gradual degradation of the thermo-optical and mechanical properties. The same FEP material also showed localised cracks, tears and losses of the mechanical integrity on Solar Max and Hubble Space Telescope Solar Array.

This paper describes, based on several flight data and on-ground tests, the parameters and causes that influence the long term behaviour of this material.