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The urgent problem to solve is how to design a kind of green and porous adsorbent that can effectively remove dye pollutants in the field of the sewage treatment. The objectives of this investigation are to incorporate zeolitic imidazolate frameworks‐8 (ZIF‐8) particles in situ onto the surface of multiwalled carbon tubes (MWCNTs) and integrate them into an agarose‐sodium alginate (ASA) double network hydrogel. The resulting composite hydrogel beads, denoted as MWCNTs/ZIF‐8/ASA (MZASA), are synthesized using calcium ion crosslinking. The addition of agarose is employed to create a dual‐crosslinked hydrogel, thereby enhancing the mechanical properties of the ASA hydrogel. By incorporating MWCNTs/ZIF‐8 nanoparticles, the surface area of the MZASA hydrogel is augmented, leading to an enhancement in dye adsorption capacity. In batch sorption mode, the maximum absorbency of the resulting hydrogel beads for methylene blue (MB) is 493.799 mg/g, which was a third greater than that of pure SA beads. Absorption of MB obeys the pseudo‐second‐order kinetic model and Langmuir isotherm model, suggesting monolayer chemisorption adsorption. Analysis of the thermodynamics proves that the entire adsorption process is exothermic and spontaneous. Moreover, the MZASA hydrogel beads show high selectivity for cationic dyes in the mixed dye test. Hence, the synthesized MZASA hydrogel beads serve as a highly effective, innovative, and reusable adsorbent for eliminating cationic dyes from water‐based solutions. [ABSTRACT FROM AUTHOR]

In this work, the CO0.5Ni0.5Fe2O4 nanoparticles modified by phosphoric acid and NCO groups were prepared as flame‐retardants and cross‐linking centers. After modification, the dispersibility and flame‐retardant properties of the nanoparticles were effectively improved. On this basis, a kind of two‐component polyester‐based anti‐smudge and flame retardant hybrid coating in situ polymerization was prepared by using dihydroxy mono‐terminated PDMS to provide low surface energy, dipentaerythritol (Di‐PE) as a charring agent to provide sufficient cross‐linking sites. Water, ink, pump oil, and cooking oil could slide off the coated surface without leaving any traces. These novel hybrid coatings exhibit excellent anti‐graffiti properties and corrosion resistance even with 2 wt% PDMS and 3 wt% modified nanoparticles content. Moreover, Si, P, and CO0.5Ni0.5Fe2O4 all resulted in the formation of a char protective layer during burning. The thermal properties and flame retardant properties of the hybrid coatings were significantly improved. The peak heat release rate (PHRR) curves and the smoke production rate (PSPR) of hybrid coatings (3 wt% modified CO0.5Ni0.5Fe2O4) decreased by 44.2%, 55.7%, respectively, compared with pure composites. Besides, the hybrid coatings can be applied to a variety of substrates, including glass, steel, and fabric. [ABSTRACT FROM AUTHOR]

Magnetic Fe3O4/waterborne polyurethane nanocomposites were synthesized based on waterborne polyurethane (WPU) and amino‐functionalized Fe3O4 by in situ polymerization. The Fe3O4 nanoparticle was found to be uniformly distributed in Fe3O4/WPU nanocomposites with linear or crosslinked structure. In addition, the formation mechanism and magnetic conduction mechanism of stable inorganic–organic nanocomposites were discussed. The experimental results showed that the thermal stability, magnetic, and mechanical properties of magnetic Fe3O4/waterborne polyurethane nanocomposites were improved by amino functionalized Fe3O4. Furthermore, the defoaming property of the emulsion and the hydrophobic property of magnetic Fe3O4/waterborne polyurethane nanocomposites were improved by the 1‐hexadecanol‐terminated prepolymer. What more, polycaprolactone (PCL)‐based Fe3O4/WPU nanocomposites have excellent mechanical properties (The tensile strength is over 30 MPa, the elongation rate is above 300%.) and magnetic properties. Magnetic Fe3O4/waterborne polyurethane nanocomposites will be used in the field of hydrophobic and microwave absorbent materials. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48546. [ABSTRACT FROM AUTHOR]