Atomic Oxygen Degradation of Polymeric Thin Films in Low Earth Orbit

Polymeric materials exposed to space environment up to 500 km altitude are affected by the upper neutral atmosphere, whose main constituent is atomic oxygen; the latter attacks hydrocarbon polymers by removing C atoms from the molecular backbones. At a macroscopic level this produces polymer erosion, which has the potential of destroying thermal covers and primary composite structures. This paper presents a methodology for predicting the erosion rates of hydrocarbon polymers exposed to the space environment via a probabilistic finite volume approach; this technique also allows predicting both the polymer thickness/mass loss and the associated degradation of thermo-optical properties.