electricity on a large scale with ultralow greenhouse gases emission. [2] Uranium is the most critical ingredient for the production of nuclear power. In order for nuclear power to be a sustainable energy generation in the future, economically viable sources of uranium beyond terrestrial ores must be developed. [3] The oceans hold ≈4.5 billion tons of uranium, [4] making them a potential huge resource to support nuclear power production for hundreds of years. [5] All that is required is the ability to capture this element from seawater in cost-and energy-efficient ways. In the last decades, researchers worldwide have tried various methods to recover uranium from seawater and aqueous solution, such as coprecipitation, [6] ion-exchange, [7] adsorption via porous organic polymers, [8,9] and organic-inorganic hybrid adsorbents. [10][11][12][13][14][15][16] Among these technologies, the adsorption approach, particularly by using fiber-based adsorbents, is recognized as the most feasible process in terms of practicality, processability, cost, and environmental concerns. [3,17] In the 1990s, Japan Atomic Energy Agency (JAEA) research teams had successfully captured over 1083 g of uranium directly from ocean by using nonwoven fabric adsorbent, firmly establishing the practicality of uranium recovery from the oceans in appreciable quantities. [3,18] Uranium extraction from seawater via fiber adsorption has recentlyThe oceans contain hundreds of times more uranium than terrestrial ores. Fiber-based adsorption is considered to be the most promising method to realize the industrialization of uranium extraction from seawater. In this work, a pre-amidoximation with a blow spinning strategy is developed for mass production of poly(imide dioxime) nanofiber (PIDO NF) adsorbents with many chelating sites, excellent hydrophilicity, 3D porous architecture, and good mechanical properties. The structural evidences from 13 C NMR spectra confirm that the main functional group responsible for the uranyl binding is not "amidoxime" but cyclic "imidedioxime." The uranium adsorption capacity of the PIDO NF adsorbent reaches 951 mg-U per g-Ads in uranium (8 ppm) spiked natural seawater. An average adsorption capacity of 8.7 mg-U per g-Ads is obtained after 56 d of exposure in natural seawater via a flowthrough column system. Moreover, up to 98.5% of the adsorbed uranium can be rapidly eluted out and the adsorbent can be regenerated and reused for over eight cycles of adsorption-desorption. This new blow spun PIDO nanofabric shows great potential as a new generation adsorbent for uranium extraction from seawater.

Vitrimers are network polymers that undergo associative bond exchange reactions in the condensed phase above a threshold temperature, dictated by the exchangeable bonds comprising the vitrimer. For vitrimers, chemistries reliant on poorly nucleophilic bond exchange partners (e.g., hydroxy-functionalized alkanes) or poorly electrophilic exchangeable bonds, catalysts are required to lower the threshold temperature, which is undesirable in that catalyst leaching or deactivation diminishes its influence over time and may compromise reuse. Here we show how to access catalyst-free bond exchange reactions in catalyst-dependent polyester vitrimers by obviating conventional ester bonds in favor of oxime−esters. Poly(oxime−ester) (POE) vitrimers are synthesized using thiol−ene click chemistry, affording high stretchability and malleability. POE vitrimers are readily recycled with little degradation of their initial mechanical properties, suggesting exciting opportunities for sustainable plastics.

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Over the past 30 years, atomic force microscopy (AFM) has played an important role in elucidating the structure and properties of polymer surfaces. AFM-based techniques have enabled the quantitative determination of the physicochemical properties of polymer surfaces with high spatial resolution and under a wide variety of conditions. Coupled with the improvements in spatial and temporal resolution, multiparametric and multifunctional characterization has revealed the delicate interplay between structure, dynamics, and properties at the surfaces of complex systems.Here we summarize some of the significant advances that have been made in synthetic polymeric materials, most in the past 10 years, where AFM has been crucial, and we provide our perspective on where AFM will be insightful in future and instrumental in advancing emerging areas.

The elastic nanofibrous aerogels can be facilely fabricated employing PVA-co-PE nanofibers suspension and demonstrate excellent candidates for environmentally sustainable applications.

Highly efficient recovery of uranium from seawater is of great concern because of the growing demand for nuclear energy. The use of amidoximebased polymeric fiber adsorbents is considered to be a promising approach because of their relatively high specificity and affinity to uranyl. The surface area, hydrophility, and surface charge of the adsorbent are reported to be critical factors that influence uranium recovery efficiency. Here, a porous amidoxime-based nanofiber adsorbent (SMON-PAO) that exhibits the highest uranium recovery capacity among the existing fiber adsorbents both in 8 ppm uranium spiked seawater (1089.36 ± 64.31 mg-U per g-Ads) and in natural seawater (9.59 ± 0.64 mg-U per g-Ads) is prepared by blow spinning. These nanofibers are obtained by compositing polyacrylamidoxime with montmorillonite and exhibit the increased surface area and more exposed functional amidoxime moieties for uranyl adsorption. The residual montmorillonite enhances the hydrophility and reduces the negative surface charge, thereby increasing the contact of the adsorbent with seawater and reducing the charge repulsion between negative amidoxime group and negative uranyl species ([UO 2 (CO 3 ) 3 ] 4− ). The finding of this study indicates that rational design of uranium recovery adsorbents by comprehensive utilizing the key factors that influence uranium recovery performance is a promising approach for developing economically feasible uranium recovery materials.

A robust, highly water stable (up to 3 weeks), microporous MOF, [Zn8(O)2(CDDB)6(DMF)4(H2O)] {where CDDB = 4,4'-(9-H carbazole-3,6-diyl)dibenzoic acid}, was synthesized based on an open N-H site by a solvothermal process and exhibited an outstanding loading capacity (around 53.3 wt%) and satisfactory release capability (64.9% and 81.9%) for 5-fluorouracil, constituting a negligible cytotoxicity effect.

For the purpose of increasing the hydrophilicity of a polylactide, a new monomer, (3S)-3-[(benzyloxycarbonyl)methyl]morpholine-2,5-dione, was successfully polymerized. The benzyl protective group of the polymer was completely removed to give poly(glycolic acid-alt-L-aspartic acid). The structures and properties of both protected and deprotected polymers were carefully studied by NMR, GPC, and DCA. It is found that the morpholine-2,5-dione derivatives with side functional groups which have no substituent on the 6 position of the morpholine ring are much more reactive than those monomers with a substituent on the 6 position of the ring in polymerization. The resulting polymer shows promising hydrophilicity, as can be seen from the DCA result.