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The durability of anion exchange membranes (AEMs) and the balance between ionic conductivity and dimensional stability have been the focus of research. To this end, we propose a new type of AEMs with vinyl imidazole as the in situ cross‐linking monomer. The rigid‐flexible balance within the membrane was adjusted by changing the arrangement of the internal segments of the polymer and introducing different monomers into the main chain. The results showed that the performance of AEMs could be effectively improved by adopting an ether‐free backbone and a cationic cross‐linking strategy. The swelling rate of all AEMs was less than 20%. The ionic conductivity of BDCP‐80 reached 102.74 mS cm−1 at 80°C. Alkaline stability tests showed that the ionic conductivity of all AEMs remained above 82% after 720 h immersion in 2 M NaOH solution at 80°C. This study demonstrated that the simple in situ cross‐linking method can effectively improve the overall performance of AEMs and provide an effective way to develop high‐performance AEMs. [ABSTRACT FROM AUTHOR]

Numerous challenges arise from metal corrosion, including economic loss, environmental pollution, and safety issues. Epoxy coatings, as a solution to metal corrosion problems, have been widely used worldwide. The improvement of epoxy coating performance is also a major focus of research. In this paper, we employed a hydrothermal method to load UIO‐66 crystals onto a two‐dimensional mica substrate, while simultaneously modifying the surface with polyethyleneimine (PEI) to enhance the compatibility of the filler in the epoxy coating. The water absorption and adhesion of the PMC‐UIO(4:1)/EP coating were optimized after the addition of the modified filler, with the adhesion strength of the PMC‐UIO(4:1)/EP coating improved to 8.28 MPa. In terms of electrochemical impedance spectroscopy, the PMC‐UIO(4:1)/EP coating manifested long‐lasting and superior corrosion resistance. Specifically, the electrochemical impedance modulus of this coating reached as high as 1011. Remarkably, even after immersion in a 3.5 wt% sodium chloride solution for 30 days, the coating maintained an impedance value order of magnitude at 109, which is unparalleled among all the composite coatings studied, demonstrating its exceptional corrosion resistance. [ABSTRACT FROM AUTHOR]

In this study, HAp(hydroxyapatite) was prepared by hydrothermal method and was successfully modified by APTES (aminopropyltriethoxysilane) to obtain APTES‐HAp nanomaterial. Firstly, the microstructure and surface morphology of HAp and APTES‐HAp were studied by Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM), and it was confirmed that HAp and APTES‐HAp composites were successfully synthesized. Secondly, SEM analysis is used to study the dispersion of APTES‐HAp in epoxy resin, and it is proved that the dispersion of HAp modified by APTES is greatly improved. Finally, the corrosion resistance of the composite coating was studied in detail by electrochemical impedance spectroscopy (EIS). The results show that the APTES‐HAp /EP composite coating impedance modulus remains 107. The breakpoint frequency (fb) is always the minimum after 30 days of immersion, which proves that the corrosion resistance of APTES‐HAp /EP composite coating is significantly improved APTES‐HAp/EP. The improvement of corrosion resistance is mainly attributed to the following two points: APTES‐HAp has good uniform dispersion and interfaces compatibility in epoxy resin, forming an effective barrier network. On the other hand, layered HAp forms physical barriers and maze effects on corrosive media. [ABSTRACT FROM AUTHOR]

Herein, a new strategy for improving epoxy coatings' anti‐corrosion performance has been developed, which combined NH2‐Ce‐MOF with graphene oxide (GO) by hydrothermal method. First, the nanocomposite material's morphology and structure (GO‐Ce‐MOF) were confirmed by Fourier transform infrared, X‐ray diffraction, TG, X‐ray photoelectron spectroscopy, and scanning electron microscope (SEM) studies. The dispersity of the composite in the epoxy coating was evaluated by SEM and mapping analysis. Meanwhile, the anti‐corrosion of as‐prepared composite coatings was investigated in detail by the electrochemical impedance spectroscopy (EIS) and the Tafel polarization curve test. The results illustrated that 2.0 wt% GO‐Ce‐MOF/EP greatly enhanced the composite coating's anti‐corrosion performance compared to other coatings. The reasons for the improvement of the anti‐corrosion performance of the composite coating are attributed to the following two aspects: On the one hand, the addition of GO can provide a physical barrier to form a labyrinth effect to slow down the invasion of corrosive media into the metal substrate, on the other hand, the modification of GO can GO‐Ce‐MOF achieve better compatibility and dispersion in epoxy resin. [ABSTRACT FROM AUTHOR]

Chitosan (CS) was used as a cross‐linking agent to modify UiO‐66‐NH2, and the modified UiO‐66‐NH2 was fixed on the mixed cellulose membrane (MCE) through vacuum filtration technology to prepare a new type of membrane. The membrane exhibited excellent hydrophilicity in the air and excellent super‐oleophobic performance underwater, and effectively separated various oil–water emulsions. When separating petroleum ether‐water emulsion, the filtration flux of the modified membrane was 2000 L m−2 h−1 higher than that of MCE, and the separation efficiency can reach more than 95%. After 10 cycles, the flux of the modified membrane was about four times of that MCE, which was 500 L m−2 h−1. Most importantly, the membrane still maintained underwater superoleophobicity in the environment of strong acid, strong base, and salt solution. [ABSTRACT FROM AUTHOR]

In this study, a novel dopamine modified graphene‐based photocatalytic membrane with Bi12O17Cl2 inserted was fabricated to modify the commercial cellulose acetate membrane via vacuum filtration method. Results showed the reduced graphene oxide (RGO)/poly(dopamine) (PDA)/Bi12O17Cl2‐CA photocatalytic composite membrane exhibited 98% removal efficiency for methylene blue (MB) within 100 minutes and 96% removal efficiency for 4‐CP within 160 minutes. Importantly, the photocatalytic composite membrane can simultaneously achieve dye degradation and oil‐water separation in only one device within a short time. And the as‐prepared membrane displayed great antifouling performance and recyclability after 10 cycles. Meanwhile, the membrane showed excellent stability in the agitated water bath or different pH conditions. In summary, the photocatalytic membrane investigated in this study opens new avenue for treatment of wastewater. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Membrane separation is a promising process for treatment of dye and oily wastewater if the antifouling capacity and recyclability can be improved. In recent years, the development of photocatalytic materials has provided new methods for research into membrane technology. RESULTS: In this study, a novel photocatalytic membrane decorated with RGO‐Ag‐TiO2 nanomaterial was fabricated by simple vacuum filtration for degradation of dye and separation of oil–water. First, TiO2 nanowires were prepared for more effective photocatalysis, reduced graphene oxide (RGO)‐Ag‐TiO2 was fabricated by a facile hydrothermal reaction, then it was directly decorated on cellulose acetate (CA) membrane using polyethylene glycol and glutaraldehyde. CONCLUSION: The as‐prepared photocatalytic membrane can simultaneously degrade dye and separate oil–water emulsions under visible‐light irradiation in a short time. The membrane has extremely high water flux (191 L m‐2 h‐1) and rejection rates (almost 100%) of dye–oil–water emulsion. More importantly, the photocatalytic membrane shows excellent antifouling capacity and recyclability, and retains relatively stable dye–oil–water permeation flux (about 27.5 L m‐2 h‐1) and high rejection rates (up to 99%) after six cycles of experiments under visible‐light irradiation. Overall, the photocatalytic membrane opens up new avenues for the treatment of wastewater. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In the study, hydroxypropyl guar gum (HPG) gel is prepared by using Nano-ZrO2 particles as the cross-linking agent. The Nan-ZrO2 particles are prepared by using oil-water interface method. The physical properties such as morphology, particle size, and crystal structure of the Nano-ZrO2 particles are analyzed by SEM, particle size analyzer, FT-IR, and XRD, respectively. The results show that the Nano-ZrO2 particles are spherical particles with a little agglomeration; these spherical particles have a tetragonal structure and higher crystallinity, and the mean diameter of the first-level grain is 24 nm. The rheological properties including shear stress, complex modulus, elasticity modulus (G′), and viscosity modulus (G′′) of the Nano-ZrO2 cross-linked HPG gel are investigated. The results show that the Nano-ZrO2 cross-linked HPG gel is a pseudo-plastic non-Newtonian fluid with higher elastic modulus (G′ > G′′) and lower tanδ (tanδ < 1, the ratio of viscous and elastic modulus), which indicate that the Nano-ZrO2 cross-linked HPG gel may have potential application in fracturing. [ABSTRACT FROM AUTHOR]

Membrane technology has been successfully applied for the removal of dyes from wastewater in the textile industry. A novel poly(vinylidene fluoride) (PVDF) membrane was prepared via blending with different dosages of Ag-TiO2-APTES composite for dyeing waste water treatment in our study. And the effect of Ag-TiO2-APTES blended into the PVDF membrane was discussed, including the rejection rate of methylene blue (MB) dye, membrane morphology, surface hydrophilicity, antibacterial activity, and a certain photocatalytic self-cleaning performance. X-ray diffraction and Fourier transform infrared characterization confirmed that Ag-TiO2 was functionalized by amount of hydroxyl group (−OH) and amino group (NH−), which provided by APTES. Contact angle measurement certified that the hydrophilicity of the membrane surface increased, with the contact angle decrease to 61.4° compared with 81.8° of original PVDF membrane. MB rejection rate was also increased to 90.1% after addition of Ag-TiO2-APTES, and the rejection of original membrane was only 74.3%. The morphologies of membranes were observed by scanning electron microscope, which indicated that Ag-TiO2-APTES had a good dispersion in membrane matrix and also improved the microstructure of membranes. Besides, UV irradiation experiments were performed on the composite films contaminated by MB, and the result showed that Ag-TiO2-APTES nanoparticle provided PVDF membrane with a certain photodegradation capacity under UV irradiation. Moreover, antibacterial activity of the composite membrane was also demonstrated through antibacterial experiment, Escherichia coli as the representative bacteria. Perhaps, this research may provide a new way for PVDF blending modification. [ABSTRACT FROM AUTHOR]

BACKGROUND Membrane fouling is a main obstacle hindering wider application of membrane technologies, and can cause a decline in flux and increased energy consumption, and more frequent chemical or membrane replacement can increase the operating costs. Membrane fouling is mainly governed by organic fouling and biofouling. In recent years, the development of new materials has provided new methods and thoughts for the research and development of antifouling and antibacterial membranes. RESULTS In this study, to obtain both a highly hydrophilic, antifouling and antibacterial poly(vinylidene fluoride) (PVDF) membrane, in situ formed silver (Ag) nanoparticles were immobilized with silica (SiO2) nanoparticles, and then chemically bound onto a PVDF ultrafiltration (UF) membrane surface. The surface modification processes were achieved through a remarkably facile and effective dip-coating method. The impacts of Ag/SiO2 nanocomposites on membrane performance were investigated when applied in membrane filtration processes simultaneously. This membrane showed higher hydrophilicity and water permeation flux. The PVDF membrane exhibited antibacterial properties and displayed better anti-fouling performance. CONCLUSION The superior performance of the Ag/SiO2-PVDF membranes and this facile, effective and scalable modification method hold great promise for their practical application. This work would also be helpful for developing new antifouling and antibacterial membrane and related materials via a convenient and large-scale method. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Multi-walled carbon nanotubes ( MWCNTs) have attracted considerable interest in the membrane field, but they are prone to aggregate in the polymer matrix and cause membrane defects. Different from blending MWCNTs in the casting solution, different ratios of APTS-functionalized MWCNTs (A- MWCNTs) were embedded on the surface of polyvinylidene fluoride ( PVDF) membranes. RESULTS FTIR and XPS demonstrated the reaction between MWCNTs and APTS. SEM and AFM images showed that new morphology and pore structure appeared in novel A- MWCNTs/ PVDF membranes compared with pure PVDF membrane. The embedding was firm because of APTS chains penetrating into the PVDF matrix, and the optimum content of A- MWCNTs was 0.05 wt%. Besides, A- MWCNTs/ PVDF membranes exhibited superior contact angle and BSA rejection than PVDF membrane. In the tests of copper ions rejection and adsorption, 0.05 wt% A- MWCNTs/ PVDF membrane gave 89.1% removal and 2.067 mg g−1 adsorption capacity compared with PVDF membrane, at just 19.66% and 0.516 mg g−1, respectively. CONCLUSIONS The existence of functional groups in A- MWCNTs such as - NH2 and - COOH, can not only increase the hydrophilicity of membranes, but also provide more adsorption sites to have a complexation reaction with Cu2+ ions. This work provides information to solve practical problems in the field of wastewater treatment. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Calcium carbonate nanoparticles (nano-CaCO3) anchored graphene oxide (GO) sheet nanohybrids (GO-CaCO3) are fabricated, and their structure can be measured by scanning electron microscope, transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction and Fourier-transform infrared spectroscopy analysis. Afterwards, composite epoxy coatings, filled with GO and GO-CaCO3 nanohybrids, are prepared via a curing process. The dispersion and anticorrosive properties of composite epoxy coatings are investigated. The results reveal that GO-CaCO3 nanohybrids achieve a homogeneous dispersion as well as reinforce corrosion resistance of epoxy coatings. Furthermore, the anticorrosive mechanisms are tentatively proposed for the GO-CaCO3/epoxy coatings. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this study, a novel dopamine‐modified TiO2 nanowire (NW)‐intercalated graphene‐oxide‐based photocatalytic (NWC) membrane was prepared by vacuum‐assisted filtration using a commercial cellulose acetate membrane as a support layer. At the same time, compared with the synthesized reduced graphene‐oxide/polydopamine/TiO2 nanoparticle composite (NPC) membrane, it was found that the NWC membrane has high water flux (273 L m−2 h−1) and removal rate (above 98%) on the dye‐oil emulsion. After 5 cycles of experiments, the NWC membrane maintained a relatively stable permeation flux and removal rate, which was significantly better than the NPC membrane. The results showed that the NWC membrane had a more uniform distribution of TiO2 NW, and had better antifouling ability, recyclability, and photocatalytic performance than NPC membrane. In summary, the NWC photocatalytic membrane of this study shows excellent water purification potential and provides a new path for photocatalytic water treatment. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48488. [ABSTRACT FROM AUTHOR]

The cover image, by Qi Chen et al., is based on the Research Article A novel photocatalytic membrane decorated with RGO‐Ag‐TiO2 for dye degradation and oil‐water emulsion separation, DOI: 10.1002/jctb.5426. [ABSTRACT FROM AUTHOR]

The cover image, by Zongxue Yu et al., is based on the Research Article A novel antifouling and antibacterial surfacefunctionalized PVDF ultrafiltration membrane via binding Ag/SiO2 nanocomposites, DOI: . [ABSTRACT FROM AUTHOR]