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Aqueous zinc‐ion batteries (AZIBs) are considered promising candidates for large‐scale energy storage due to their high safety, low cost, and environmental friendliness. As a core component, separator plays a unique yet oftentimes overlooked role in providing electrochemical stability in AZIBs. This concept focuses on the exquisite structure‐property relationship of separators, highlighting three forms of these components and their structural design requirements, i. e., traditional membranes, solid‐state electrolytes, and electrode coatings. The mechanism by which separators influence the zinc anode and the cathode is discussed. The article also identifies the challenges and potential future directions for functional separators in the development of high‐performance AZIBs. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐metal batteries are prospective energy storge devices due to their intrinsically high safety and cost effectiveness. Yet, uneven deposition of zinc ions in electrochemical reduction and side reactions at the anode interface significantly hinder their development and application. Here, we propose a solvation‐interface attenuation strategy enabled by a frustrated tertiary amine amphiphilic dipolymer electrolyte additive. The configuration of superhydrophilic segments with covalently bonded lipophilic spacers enables coupled steric hindrance/coordination, which establishes a balanced push‐pull dynamic of dipolymer‐H2O‐Zn2+. Such interplay reconstructs the solvation structure of Zn2+ and allows the formation of a stable dipolymer‐inorganic hybrid solid electrolyte interface (SEI) layer. This SEI layer effectively shields the zinc‐metal anode from water and anions, significantly reducing side reactions. In addition, the dipolymer adsorbed at the zinc‐metal anode interface regulates the interfacial electrochemical reduction kinetics and ensures uniform zinc deposition. As a result, the Zn−Zn symmetric cells with dipolymer‐containing electrolyte exhibit remarkable cycling stability exceeding 5800 h (242 days). The Zn‐NVO batteries and Zn‐AC hybrid ion supercapacitors also deliver stable cycling for up to 1440 h (60 days) with high‐capacity retention over 80 %. This research demonstrates the potential to facilitate the development and commercialization of zinc‐based energy storage devices. [ABSTRACT FROM AUTHOR]

The elasticity and aging resistance of nitrile butadiene rubber (NBR) will be reduced by reinforced filler. Herein, we report that polydopamine (PDA) polymerized in situ on graphene oxide (GO) to obtain polydopamine‐graphene oxide (PDA‐GO) nanofiller for simultaneously improving strength, elasticity and thermal oxidative aging‐resistant performance of NBR. The structure, composition and morphology of PDA‐GO and NBR composites were characterized. The effect of PDA‐GO on the performance of NBR was investigated. Results show that PDA microspheres improved the dispersion of GO in matrix. With incorporation 3 phr of PDA‐GO, the tensile strength of NBR raised from 3.8 to 9.2 MPa. It is satisfactory that the elasticity is also improved significantly. PDA‐GO/NBR composite equips better thermal oxidative stability and aging resistance. The tensile strength of 3 phr‐PDA‐GO/NBR after aging is even 3.4 MPa higher than that of unfilled NBR before aging. Our work proposes an insight for the manufacture of rubber composites with high strength, elasticity and aging resistance. Highlights: GO modified by PDA is prepared via an in‐situ polymerization process.In situ polymerized PDA microspheres greatly promotes the dispersion of GO in NBR matrix.NBR filled with PDA‐GO shows a superior strength and elasticity simultaneously.PDA‐GO endows NBR with prominent performance in aging resistance. [ABSTRACT FROM AUTHOR]

To extend the release time of drug carriers with the thermoresponsive behavior of upper critical solution temperature (UCST), P(AAm-co-AN) microgels are prepared by precipitation polymerization. It is found that the microgels exhibit the UCST-type response and the microgel shows swelling and disperses well when the temperature is higher than the critical temperature. Because the microgel can swell and shrink reversibly with the change in solution temperature, it can be used as a drug carrier. Compared with the micellar carrier, the microgel carrier's structure is more stable and has a better sustained-release effect. [ABSTRACT FROM AUTHOR]

The NBR/G@Fe3O4 composites with good electromagnetic shielding properties are prepared by solution blending, previously, the “G@Fe3O4 composite particles” were obtained by a simple co-precipitation method. The structures of G@Fe3O4 are characterized by Fourier infrared spectroscopy (FTIR), X-ray diffraction (XRD), Raman spectroscopy (Raman), Scanning electron microscopy (SEM), and the graphene content in the composite particles was analyzed by thermogravimetric analysis (TGA). The electromagnetic shielding performance of NBR composites is tested by microwave vector network analyzer. The results show that the average electromagnetic shielding effectiveness of NBR/G@Fe3O4 composites in X-band (8.2–12.4 GHz) can reach 80.4dB, and when the thickness is only 2.1 mm and the filler content is 15 phr can reach 28.2dB, which shield 96.2% of the energy of incident electromagnetic waves. Due to the introduction of magnetic particle Fe3O4, the NBR/G@Fe3O4 composites have better shielding performance than NBR/G composites at the same graphene content. The electromagnetic shielding effectiveness of NBR/G@Fe3O4 composites with 9.3 phr of graphene is basically the same as that of NBR/G composites with 12.4 phr of graphene. [ABSTRACT FROM AUTHOR]

As a potential candidate for next‐generation energy storage systems, Li–O2 batteries (LOBs) with their attractive theoretical energy density have triggered great interest. However, tough issues of sluggish oxygen reduction reaction/oxygen evolution reaction (ORR/OER) kinetics, poor rechargeability, superoxide‐derived side reactions, and Li‐metal corrosion in LOBs limit their practical applications. Herein, a poly(2,2,2‐trifluoroethyl methacrylate) (PTFEMA) additive is introduced into the typical electrolyte, giving superior cycling performance to LOBs. Enabling strong solvation of Li+, PTFEMA regulates a uniform Li+ flow at the cathode and anode sides of LOBs. Induced by homogeneous Li+ flux and favorable adsorption with superoxide species, PTFEMA promotes superoxide transformation in the ORR and inhibits superoxide‐induced parasitic reactions. Uniform Li+ flux gives evenly‐distributed Li2O2 that can be completely decomposed during OER. In addition, PTFEMA protects Li‐metal against corrosion from O2, superoxide, and byproducts shuttle. Hence, accelerated ORR/OER kinetics, facilitated rechargeability, suppressed superoxide‐derived side reactions, and well‐protected Li‐metal can be simultaneously realized with PTFEMA, resulting in significantly enhanced electrochemical performance of LOBs. This electrolyte engineering involving facile multifunctional polymer additives provides a practical alternative to complex componential optimization toward commercial LOBs and gives insight to the understanding of uniform Li+ flux on reaction kinetics and reversibility. [ABSTRACT FROM AUTHOR]

Zirconium phosphate (α‐ZrP) was modified by o‐phenylenediamine (OPD) grafting to its surface, named ZPD, and used to improve thermal‐oxidative stability of nitrile butadiene rubber (NBR) by direct blending method. The results of Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA), X‐ray diffraction, and contact angle test, demonstrated that OPD was grafted to the surface of α‐ZrP successfully. Scanning electron microscopy results showed that OPD could effectively improve the interaction between α‐ZrP and NBR and a better the dispersion of α‐ZrP in the rubber matrix. The fracture strength of the NBR composites was increased by 3.3 Mpa with the addition of 3 phr ZPD fillers, respectively, compared with unmodified NBR/α‐ZrP composites. In addition, TGA, DMA, and FWO analysis showed ZPD fillers, combined lamellar barrier of α‐ZrP with radical trapping ability of OPD, could retard oxidative cross‐linking and fracture reaction of rubber chains, and improve the thermal‐oxidative aging resistance of the NBR composites. This work provides a practical and effective methodology for surface modification of α‐ZrP and preparation of high‐performance NBR composites. [ABSTRACT FROM AUTHOR]

Recently, the research of blending anti‐aging modification of nitrile butadiene rubber (NBR) has been widely reported, but the surface effect in the rubber aging process has been obviously ignored. Starting from the surface microstructure design, the construction of surface protection barrier may be a new anti‐aging way. In this paper, the surface superhydrophobic NBRsurf‐polydopamine (PDA)‐(SiO2‐g‐PFOMA) is prepared through a ordered modification of two‐step physical deposition to NBR with PDA and SiO2 grafted with Perfluorooctylmethacrylate (SiO2‐g‐PFOMA). By comparing the mechanical properties before and after aging, it is found that the DA surface pretreatment significantly improves the NBR thermo‐oxidative aging. On this basis, surface superhydrophobic SiO2‐g‐PFOMA microstructure has set up to further prevents NBR from the attack of corrosive media such as acid, alkali, salt and water. After aging in HCl solution at 90°C for 96 h, the fracture strength, elongation and aging coefficient of NBRsurf‐PDA‐(SiO2‐g‐PFOMA) compared with unmodified NBR(KB) were increased by 2.28 MPa, 48.76% and 0.18, respectively. This work can offer an surface anti‐aging technology to NBR. [ABSTRACT FROM AUTHOR]

Stimuli‐sensitive polymers are a class of macromolecular system with "intelligent" behavior. Herein, a copolymer of poly (acrylamide‐co‐2‐acrylamido‐dodecyl sulfonate), which has salt‐sensitive and thermosensitive properties, is synthesized via precipitation polymerization. Its aqueous solution exhibits a clear sol state, while a gel is obtained via salt‐induction by addition a certain amount of NaCl. More interestingly, the gel can transform into clear sol again upon heating, which exhibits a phase transition of upper critical solution temperature in NaCl solution. The dual responsive behaviors of copolymer solutions are studied via rheological measurements. Then fluorescence spectrum, zeta potential test, and dynamic light scattering are employed to investigate molecular interaction in aqueous solution under varying conditions. It is found that dual responsive behaviors are caused by electrostatic interaction and hydrophobic association. At last, oily emulsion wastewater treatment indicates that this polymer shows characteristics of "smart flocculant" and has potential application prospect. [ABSTRACT FROM AUTHOR]