Tribological and AO irradiation resistant properties of 3D printing polyimide-POSS composites

To address the requirements of polyimide (PI) parts in the harsh Low Earth Orbit (LEO), a 3D printable PI composite with superior tribological and atomic oxygen (AO) irradiation resistant properties was proposed by employing methacryloxypropyl polyhedral oligomeric silsesquioxane (MPA-POSS) as a crosslinking agent in the photosensitive PI inks to obtain POSS-contained PI composite (PI-POSS composite). The resultant PI-POSS exhibits unique comprehensive performance including excellent AO irradiation resistance of an erosion yield of 2.86 x 10-24 cm3/atom, 50 % lower than that of PI without POSS, and anti-wear and friction reducing properties with a coefficient of friction of 0.1 and a wear rate of 4.4 x 10-6 mm3/N center dot m. Importantly, the PI-POSS inks have excellent VP 3D printability, enabling the creation of complex, AO irradiation resistant, self-lubricating PI-POSS parts. These findings highlights the significant potential of such PI-POSS composite in aerospace applications within LEO.