European non-reflective thin polymer films for space sails

Kurzfassung

In low Earth orbit (LEO), ATOX is highly reactive and erodes spacecraft materials over time. ATOX-resistant materials for drag sails, flexible solar arrays, thermal insulation and other structures exposed directly to the space environment, and especially in ram direction, are essential to ensure durability and long lifetime of satellites in LEO. Furthermore, the growing number of satellites creates bright streaks in telescope images, disrupting optical and infrared astronomy, and could cause confusion and sometimes fear among those unfamiliar with the phenomenon. This increases the necessity to consider “dark and quiet skies” in the design process of satellites. A German-Austrian consortium develops new ATOX-resistant thin film products, considering the needs to ensure dark and quiet skies, and especially meeting the needs of the European market. The development is conducted under the ESA funded General Support Technology Programme (GSTP) Project ProFilm (4000145511/24/NL/KK/mdu; however, the views expressed herein can in no way be taken to reflect the official opinion of ESA). With modified polyimides two polymer films, a black and transparent one, are produced with different thicknesses. The thin films are further processed depending on the applications, for example applying coatings, perforations, or adhesives. With the first prototype materials that have been produced, initial tests were carried out to determine mechanical and thermo-optical properties. Those parameters were determined before and after thermal cycling. For the future production of the thin films an upscaling of the production facilities is currently being implemented. The initial test results as well as the planned qualification test campaign, which includes thermal cycling, UV-testing, and ATOX-testing are presented. This paper introduces thin films for space, made in Europe, boosting LEO endurance while enabling dark skies with next-gen space sails, solar arrays, and thermal insulation.