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In this contribution, the advanced aromatic polymers with excellent antiatomic oxygen (AO) performance were designed and synthesized using molecular precursor strategy and copolymerization of polyhedral oligomeric silsesquioxane (POSS). A soluble poly(p-phenylene benzobisoxazole) (PBO) precursor, that is, TBS-PBO (tert-butyldimethylsilyl was denoted as TBS), was designed to overcome the poor solubility of PBO in organic solvents. Then the new copolymer of TBS-PBO-POSS was synthesized by the copolymerization of TBS-PBO and POSS, which possessed good solubility and film-forming ability in common organic solvents, such as N-methylpyrrolidone, N,N-dimethylacetamide, and dimethyl sulfoxide. More importantly, the TBS-PBO-POSS films exhibited outstanding antiatomic oxygen properties because of the incorporation of POSS monomers with cagelike structure into the main chain of copolymer, which drastically reduced the AO-induced erosion owing to the formation of the passivating silica layer on the surface of polymers. When the TBS-PBO-POSS films were exposed to AO effective fluences of 1.5495×10(20) atom cm(-2) (5 h) and 4.6486×10(20) atom cm(-2) (15 h), the relative mass loss was merely 0.19% and 0.41%, respectively. This work provides a new perspective and efficient strategy for the molecular design of aromatic heterocyclic polymers possessing excellent combination properties including processing convenience and antioxidative and mechanical properties, which can be employed as potential candidates to endure the aggressive environment encountered in low earth orbits.

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High-performance microwave-absorbing materials (MAMs) derived from metal−organic frameworks (MOFs) have attracted considerable attention due to their tunable chemical composition and microstructure. In this contribution, a core−shellstructured Co/MnO/C nanocomplex was prepared using a CoMn-MIL MOF by a facile hydrothermal synthesis and subsequent pyrolysis process. The optimal microwave absorption (MA) property of the as-prepared Co/MnO/C nanocomplex was achieved by the regulation of the Co 2+ /Mn 2+ molar ratio. The minimum reflection loss (RL min ) of the Co/MnO/C-31 nanocomplex was low to −55.0 dB at 16.2 GHz with a thickness of 1.49 mm, and the effective absorption bandwidth (EAB) was high to 5.95 GHz (12.05−18 GHz) at a thickness of 1.8 mm. The mixedmetal nanocomplex with the core−shell structure exhibited outstanding MA performance, corresponding to the synergetic effect of the magnetic and dielectric loss. It provides a high efficiency strategy for rendering low reflection loss and broad EAB to high-performance MAMs.

Depression is one of the top global issues, which induces several serious health consequences both physically and mentally. The field of nutritional psychiatry has generated observational and efficacy data supporting...