Effect of atomic oxygen and ultraviolet on surface structure and composition of Kapton/Al film

Atomic oxygen (AO), near ultraviolet (NUV) and vacuum ultraviolet (VUV) irradiation test of Kapton/Al second surface mirror film was conducted using laser-induced AO simulation facility; the mass, solar absorptance, surface structure and composition were investigated. The results indicate that the mass of Kapton/Al film is decreased with increasing irradiation time, but the solar absorptance displays entirely different trend, which is increased with increasing irradiation time. After irradiation, the quantity of the main functional groups in Kapton/Al film surface presents downtrend basically. The breakage of C-C and C-N bonds and new chemical bond creation in Kapton/Al film surface are considered mechanisms of the degradation, and gas molecule volatilization leads to the mass loss of Kapton/Al film.