5/16/2023 0 Comments Atomic mac![]() Moreover, studies have shown that introducing POSS groups into the polymer matrix or copolymerizing POSS with polymer monomers can significantly improve the mechanical properties (strength, modulus, rigidity) and resistance to AO radiation of the polymer material,. Recently, polyhedral oligomeric silsesquioxane (POSS) and its derivatives have been widely used as space polymer composite additive to reduce radiation damage due to high thermal stability, oxidation resistance, high toughness, flame resistance, and non-volatile substances. Several studies have proven that AO has strong reactivity and causes severe erosion damage to space lubricants, such as chemical bond cleavage, decomposition, oxidation, and polymerization. Spacecraft operating in low-earth orbits ranging from 200 km to 700 km, suffer severe damage from atomic oxygen (AO). However, these space lubricants cannot satisfactorily perform in harsh space conditions, such as high vacuum, bombardment by charged and neutral particles, and intense radiation. At present, globally popular space lubricants include polyalkylcyclopentane (MAC or multi alkyl cyclopentane), silicone hydrocarbon oils, perfluoropolyether, fluor chlorophenyl-containing silicone oils, ionic liquids, and their corresponding greases. As the stability of moving parts in space equipment is directly related to the performance of lubricants, , researchers have spared no efforts in enhancing the composition and molecular structure of lubricants to improve their performance. The vigorous development of aerospace equipment, such as satellites, space stations, and spacecraft, have made the development of long-life space lubricants increasingly critical. In recent years, the continuous progress made in the miniaturization and precision of industrial machinery, as well as the efforts made to make machinery more intelligent, have led to increasing challenges in the development of traditional lubricants.
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