The space environment raises many challenges for new materials development and ground characterization. These environmental hazards in space include solar radiation, energetic particles, vacuum, micrometeoroids and debris, and space plasma. In low Earth orbits, there is also a significant concentration of highly reactive atomic oxygen (AO). This Progress Report focuses on the development of space‐durable polyimide (PI)‐based materials and nanocomposites and their testing under simulated space environment. Commercial PIs suffer from AO‐induced erosion and surface electric charging. Modified PIs and PI‐based nanocomposites are developed and tested to resist degradation in space. The durability of PIs in AO is successfully increased by addition of polyhedral oligomeric silsesquioxane. Conductive materials are prepared based on composites of PI and either carbon nanotube (CNT) sheets or 3D‐graphene structures. 3D PI structures, which can expand PI space applications, made by either additive manufacturing (AM) or thermoforming, are presented. The selection of AM‐processable engineering polymers in general, and PIs in particular, is relatively limited. Here, innovative preliminary results of a PI‐based material processed by the PolyJet technology are presented.

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First, a simple model describes theoretically the processes involved in the irradiation of solid targets by femtosecond laser pulses and predicts the optimal target and laser parameters for efficient nanoparticles synthesis. Then, we show experimental evidence for successful synthesis of aluminum nanoparticles. Nanoparticles size distribution, morphology, atomic structure, and chemical composition are determined by various techniques, including x-ray diffraction, atomic force microscopy, scanning and transmission electron microscopy, and energy dispersive spectroscopy.

Hybrid inorganic/organic polymers have been prepared by copolymerizing a polyimide having the same chemical repeat unit as Kapton with an open-cage polyhedral oligomeric silsesquioxane (POSS). These POSS/polyimide hybrid polymers are Kapton-like polymers containing POSS nanoparticles that are chemically bound into the polymer chain. Samples of these POSS polyimides, as well as polyimide controls, have been exposed to a hyperthermal 0-atom beam that is produced by a laser-detonation source. Exposed and unexposed surfaces have been characterized by surface profilometry, atomic force microscopy, and X-ray photoelectron spectroscopy The data indicate that the POSS-containing polyimides have significantly lower erosion yields than Kapton, because they form a surface SiO2 layer which passivates the surface and protects the underlying polymer from further 0-atom attack. These results suggest promise for the use of a POSS polyimide polymer as a "drop-in" replacement for Kapton on spacecraft operating in the low-Earth orbital environment.