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The growing demand for fuel and industrial products has resulted in increased global CO2 emissions, which has accelerated global warming and made this an issue of widespread concern. Therefore, there is an urgent need to develop improved methods for CO2 fixation and conversion. Porous organic polymers (POPs) are solid frameworks that can be used for this purpose and can be prepared by so-called "bottom-up" methods. Being one kind of POP, hypercrosslinked polymers (HCPs) have emerged as a promising platform for CO2 capture and conversion, because of their high specific surface areas, variable pore characteristics, superior stabilities, and modifiable surface functionalities. In addition, innovative green methods of synthesis enable the environmentally friendly production of HCPs. In this review, we provide an update on the synthesis and utilization of HCPs for CO2 capture and conversion. First, we introduce green routes for the synthesis of HCPs, followed by a comprehensive summary of various methods for CO2 capture and conversion. Our primary emphasis is on the utilization of HCPs for CO2 fixation (gas storage) and gas separation, with particular attention given to CO2 selectivity and recoverability. Additionally, we explore the potential of HCPs in the conversion of CO2 into valuable compounds. Ultimately, we present thought-provoking suggestions to facilitate the future advancement of CO2 fixation technologies, harnessing the inherent capabilities of HCPs. [ABSTRACT FROM AUTHOR]

Microporous organic polymers (MOPs) and metal oxide hybrid composites are considered valuable coating materials because of their versatility derived from the synergistic combination of MOPs' inherent dispersibility and the distinctive properties of metal oxides. In this study, we present the synthesis of sea-urchin-like MOPs hybridised with silver oxide nanoparticles (Ag2O NPs) to fabricate antibacterial composites suitable for potential antibacterial coating applications. Ag2O NP-decorated urchin-like MOPs (Ag2O@UMOPs) were synthesised by employing a combination of two methods: a one-pot Lewis acid–base interaction-mediated self-assembly and a straightforward impregnation process. The as-prepared Ag2O@UMOPs demonstrated high antibacterial efficacy against both E. coli (G−) and S. aureus (G+). The antibacterial mechanism of Ag2O@UMOPs mainly involved the synergistic effects of accumulation of Ag2O@UMOPs, the release of Ag+ ions, and the generation of reactive oxygen species. The exceptional processability and biosafety of Ag2O@UMOPs make them ideal organic coating materials for convenient application on various substrates. These remarkable features of Ag2O@UMOPs provide an effective platform for potential antibacterial applications in biological sciences. [ABSTRACT FROM AUTHOR]

Electrospinning is a simple route to generate polymer-based fibres with diameters on the nano- to micron-scale. It has been very widely explored in biomedical science for applications including drug delivery systems, diagnostic imaging, theranostics, and tissue engineering. This extensive literature reveals that a diverse range of functional components including small molecule drugs, biologics, and nanoparticles can be incorporated into electrospun fibres, and it is possible to prepare materials with complex compartmentalised architectures. This perspective article briefly introduces the electrospinning technique before considering its potential applications in biomedicine. Particular attention is paid to the translation of electrospinning to the clinic, including the need to produce materials at large scale and the requirement to do so under Good Manufacturing Practice conditions. We finish with a summary of the key current challenges and future perspectives. [ABSTRACT FROM AUTHOR]

A structured spinneret comprising two acentric needles nested into a third metal capillary was developed to conduct three-fluid electrospinning processes. With an exterior solvent surrounding two core fluids arranged side-by-side, high quality polyvinylpyrrolidone/shellac Janus nanofibers could be prepared, which was not possible using a standard side-by-side spinneret without this innovation. [ABSTRACT FROM AUTHOR]

The preparation of Janus fibers using a new side-by-side electrospinning process is reported. By manipulating the angle between the two ports of the spinneret emitting the working fluids, Janus nanofibers with tunable structures in terms of width, interfacial area and also volume of each side can be easily fabricated. [ABSTRACT FROM AUTHOR]

Novel and highly tuneable pulsatile drug delivery systems have been prepared through the electrospinning of a blend of poly(ethylene oxide) (PEO), sodium alginate (SA), and sodium ibuprofen (SI). The resultant fibres contain crystallites of SI embedded in a PEO–SA matrix, and rather than being obtained as flat mats on the collector plate form novel three dimensional structures extending upwards the needle. Fibres were prepared with a range of loadings of SI and SA. It was found that at pH 6.8 (reminiscent of the intestinal tract) the fibres dissolve very rapidly, freeing all the embedded drug within ca. 20 minutes. However, at pH 3 (representative of the stomach pH in the fed state or in older patients) an unusual two stage release mechanism is seen. This comprises a rapid burst release, followed by a period where no further drug is released for ca. 120–150 minutes, and then a final stage of release freeing the remainder of the drug into solution. The amount of release in the initial stage, and the length of time between the first and final drug release stages, can be controlled by adjusting the SI and SA contents of the fibres respectively. This results in highly tunable pulsatile release materials. [ABSTRACT FROM AUTHOR]

We show that coaxial electrospinning using organic solvent as the sheath fluid is a viable way to produce tailor-made nanofibers composed of polyvinylpyrrolidine, tristearic and naproxen. Self-assembled hybrid nanoparticles are generated from the composite nanofibers under aqueous conditions and particle size has a linear relationship with fiber diameter. [ABSTRACT FROM AUTHOR]

The preparation of Janus fibers using a new side-by-side electrospinning process is reported. By manipulating the angle between the two ports of the spinneret emitting the working fluids, Janus nanofibers with tunable structures in terms of width, interfacial area and also volume of each side can be easily fabricated.