Polymer Coating-Based Contaminant Control/Elimination for Exo-S Starshade Probe

Our First Contact Polymer (FCP) is an easy-to-apply, residue-less, peelable strip coat that protects and cleans optics, detectors, and other sensitive surfaces, restoring them to a pristine condition. Using FCP is as simple as spraying or brushing it on a surface of interest, allowing it to dry for 15 minutes, and stripping off the rugged coating when desired. Multiple measurements, including at NASA’s Goddard Space Flight Center, show that FCP cleans better than any existing method, including the complicated, expensive, and hazardous CO2 snow, leaving no detectible residue. FCP is used to clean telescope optics at the Keck Observatory, GTC in the Canary Islands, Vandenberg Airforce Base, etc. The polymer was used by LIGO to clean the optics that enabled its breakthrough discovery of gravitational waves, and enables the THAAD missile interceptor by protecting and cleaning its optics. FCP was even used at the Smithsonian Institute to clean irreplaceable gems such as the Hope Diamond, demonstrating potential uses far beyond optics. Our technology is a crosscutting solution enabling the demanding cleanliness requirements of the Exo-S Starshade probe’s occulter, reducing the duration and cost of meeting Planetary Protection requirements without damaging sensitive components, and providing cleanroom-level cleanliness without the cleanroom, including for semiconductor manufacturing. Since our Red FCP exhibits anomalously high adhesion to certain metals and the amorphous metallic glass of Starshade petal edges, we developed in Phase I a variant with lower adhesion to metals. While the resulting adhesion was too low to be optimal, it demonstrated the adhesion tunability of our product. In Phase II, we produce 18 variants, identifying the lowest-cost one that provides optimal adhesion to protect, clean, and minimize the contribution of peeling to a mission’s alignment error budget. We also develop Standard Operation Procedures and training for application and removal.