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Membranes that contain a high fraction of amorphous poly(ethylene glycol) (PEG) are attractive for selective removal of CO 2 from H 2 streams, but crystallization of PEG chains restricts both flux and selectivity. The high thickness of solution-cast membranes also limits flux. This study demonstrates the formation of composite, PEG-containing membranes through atom transfer radical polymerization of poly(ethylene glycol methyl ether methacrylate) from initiator-modified, porous substrates. The resulting membrane skins are only 50-500 nm thick, and copolymers that contain a mixture of short and long PEG side chains do not readily crystallize. The smaller PEG chains (8-9 ethylene oxide units) prevent crystallization, while the presence of longer side chains (23-24 ethylene oxide units) allows the membranes to maintain a CO 2 /H 2 selectivity of 12 at room temperature. This work examines the effect of side-chain length on polymerization rate as well as the permeability, selectivity, and crystallinity of copolymer films. Reflectance FTIR spectroscopy reveals the fraction of different monomers incorporated into copolymer films and demonstrates when crystallization occurs.

As an important type of reactive oxygen species (ROS), hypochloric acid (HClO) is closely linked with our daily life, and its convenient and rapid detection is very significant and imperative. Fluorescent and visual probes are being recognized as powerful and convenient tools for detection of ROS in the environment and living organisms by visualizing and imaging. In this contribution, a new metal–organic framework-based fluorescent probe UiO-68-PT, which was generated from a phenthiazine-decorated benzimidazole bridging dicarboxyl ligand and ZrCl4 under solvothermal conditions via in situ one-pot approach, is reported. The obtained UiO-68-PT features a unique HClO and Vitamin C-triggered reversible redox process, which is accompanied by both visual and fluorescence changes. Therefore, it can be a highly sensitive, specific, and reusable sensor to detect HClO species in water via both visual and fluorogenic observation (turn-on). Furthermore, its mixed membrane material (MMM) was fabricated by the combination of UiO-68-PT and poly­(vinyl alcohol), and the obtained hydrophilic MMM can be used as a reversible colorimetric card for visual detection of the HClO in aqueous solution.

Herein, we report a inorganic photothermal agent CuS and organic photosensitizer BODIPY loaded composite nanoscale COF material via a stepwise post-synthetic modification. The obtained CuS@COF-BDP can be a dual-mode therapeutic...

An absorbent for benzene series with silica/poly(styrene-co-butyl acrylate) core/shell structure was prepared via emulsion polymerization. The effects of emulsifier dosage, monomer concentration, and crosslinker dosage on the absorption of the core/shell composite particles were investigated. The composite particles with good absorbency could be obtained when the emulsifier concentration was 2.5 g/L, monomer concentration was 40 g/L, crosslinker dosage was 2.0% (based on the total mass of the monomer), and the initiator dosage was 1.0%. The composite particles exhibited a rapid absorption and the absorption process conformed to the quasi-second order kinetics. Fourier-transform infrared spectroscopy, scanning electron microscope, and energy dispersive spectrometer (EDS) showed the presence of copolymer layer on the surface of silica. The work provided a new path to fabricate novel composite absorbent particles for a wide range of applications.