The highly reactive atomic oxygen (ATOX) is a severe hazard to spacecraft materials situated in low Earth orbits, especially for long duration space missions carried out for example with CubeSats. Organic materials such as polyimide films, e.g. Kapton, commonly used for electrical insulation in solar arrays are especially vulnerable to its effects and their erosion risks producing electrical arcs and a loss of power.

The deployment of large solar arrays is a critical step during space missions, and they can be obstructed by large cable harnesses which may produce large undesired and erratic torques. In contrast to common round wires, Flexible Flat Cables (FFC) produce low repeatable torques ensuring safer deployments. However, these Kapton-based cables are more vulnerable to ATOX due to their larger exposed surface area, and hence require protection. A Fluorinated Ethylene Propylene (FEP) layer is used as a protective barrier.

Solar panels require sunlight to produce power, but also risk overheating from it reducing their efficiency. Hence, solar panels must rely on passive cooling mechanisms to achieve better efficiencies through a low solar absorptance to emittance ratio. A new white coloured Kapton polyimide film has recently been developed with these properties. Solar cells laid over this material would be able to provide power more efficiently to the spacecraft than when laid over other common insulation materials. Studying the effects of ATOX on this material is vital to its implementation.

This paper presents the collaboration work of DHV and ESA conducted during the Materials4CubeSats Testing Campaign. The paper focuses on the study and preliminary results of the effects of atomic oxygen on these materials following exposure to atomic oxygen at the LEOX facility in ESTEC. The test evaluated their erosion rate, thermo-optical properties, surface conductivity, and erosion morphology through Scanning Electron Microscopy (SEM) before and after the test.