Facile synthesis of atomic oxygen-resistant methyl silicone rubber-coated Kapton film for photovoltaic solar array blanket in low Earth orbit.

A highly flexible coating deposited on organic substrates is one of the most suitable techniques for efficient atomic oxygen (AO) resistance in low Earth orbit (LEO). In this study, a highly homogeneous methyl silicone rubber coating as an AO-tolerant material was fabricated on a flexible Kapton film by a spraying process used in a photovoltaic solar array blanket. The produced silicone rubber coating has excellent AO resistance and exhibits a low shrinkage tendency after evaluating the effect of atomic oxygen on the erosion kinetics, surface morphology, and surface composition of this coating. The erosion yield of the silicone rubber-coated Kapton, which was less than 3.1% of that of the Kapton, was less than 0.92 × 10⁻²⁵ cm³ atom⁻¹ under an AO fluence of 4.04 × 10²¹ atoms cm⁻² (equiv 10 years of AO exposure in the LEO with an altitude of 500 km). It suggests that the silicone rubber layer can effectively prevent AO from eroding Kapton. In addition, a SiO₂ passivation layer was formed on the surface of the silicone rubber coating during AO irradiation, which demonstrated a "self-reinforcing" protection mechanism. This work also provides a facile method for designing and preparing large-scale flexible protective coatings with excellent AO resistance. [ABSTRACT FROM AUTHOR]