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This work presents the fabrication of a photocatalytic hydrogel band through facile one-pot processes of mixing with TiO2 nanotubes (TiNT)/graphene oxide sheets (GO)/polyvinyl alcohol (PVA), in situ photoreduction of GO and freeze–thaw gelation. The interactions between TiNT/rGO/PVA make the constructed porous gel network possess good mechanical strength with flexibility and self-healing capability. The gelation matrix also allows the TiNT/rGO/PVA hydrogel band to easily adhere to various smooth surfaces. The structural and optical analysis of the TiNT/rGO/PVA hydrogel bands indicated that the binding of rGO on TiNT can boost the photocatalytic activity by accelerating charge separation and inhibiting charge recombination of TiO2. Due to the combined effects of enhanced activity, porous features to facilitate molecular diffusion, and improved mechanical strength, the TiNT/rGO/PVA hydrogel bands exhibited excellent photocatalytic performance for the decomposition of dyes with well-maintained activity without a loss after repeated usages. These results showed the potential of hydrogel-based photocatalytic systems for more convenient and reliable usages in environmental remediation. [ABSTRACT FROM AUTHOR]

Due to the unique properties of titanium (Ti) and its alloys, it has a particularly wide range of applications in aerospace, automotive, medical and other fields. However, the problems of low surface hardness, high friction coefficient and low wear resistance of Ti alloys limit its development to a certain extent. The destruction of Ti and its alloys often occurs on the surface of materials such as wear damage, corrosion, and oxidation resistance. Therefore, the exploration and application of surface strengthening technology is particularly important. The cathodic plasma electrolytic deposition (CPED) technology, as a surface modification technology, can achieve better adhesion and facilitate the material to achieve better comprehensive performance. This paper briefly introduces the basic concepts, principles and development progress of CPED. Starting from the preparation of ceramic coatings, metal coatings, diamond-like carbon films and composite coatings, it summarizes the application of CPED in Ti and its alloys. Applications in alloys to improve thermal oxidation resistance, wear resistance, corrosion resistance, and film-based adhesion. At the end, its development in the new era environment is prospected. [ABSTRACT FROM AUTHOR]

Water pollution is a serious problem in both developed and developing countries. Several methods have been used to purify wastewater, among which photocatalytic decomposition is widely used to purify organic pollutants in wastewater. In this work, hollow nanospheres of titanium dioxide TiO2 were first prepared by the carbon sphere template method and sol–gel method, and then, the hollow nanospheres of titanium dioxide (TiO2) were compounded with silicon dioxide (SiO2) by the impregnation method to generate complexes with different ratios of hollow nanoparticles of titanium dioxide and silicon dioxide. The best degradation performance of the h-TiO2/SiO2 photocatalytic materials was achieved when the ratio of h-TiO2 to SiO2 used was 5:1. The cyclic decomposition efficiency of the 5:1 h-TiO2/SiO2 composites showed only a slight change in the photocatalytic capacity compared to the first cycle, thus ensuring the durability of the samples. However, quenching experiments yielded that hydroxyl radicals play a major role in the degradation process, and possible reaction mechanisms are discussed in detail. The high photocatalytic performance of the environmentally friendly h-TiO2/SiO2 nanosphere photocatalysts makes them ideal for water purification applications and offers potential applications for the utilization of solar energy to effectively reduce environmental pollution. The h-TiO2/SiO2 nanophotocatalysts can not only degrade dyes but can also be valuable for self-cleaning glass applications. [ABSTRACT FROM AUTHOR]

Modification of fillers and enhancement of the dispersion and compatibility of fillers in a rubber matrix is an effective way to improve the comprehensive performance of rubber. In this work, graphene oxide (GO) was modified with each of polyvinylpyrrolidone, 1‐allyl‐3‐methylimidazole hydrochloride and 1‐butyl‐3‐methylimidazole hexafluorophosphate. Then, modified GO/natural rubber (NR) composites were fabricated using a latex‐mixing method. By combining experiments and molecular simulation, we investigated the relationship between the microstructures and properties of the modified GO/NR composites. Results showed that the polyvinylpyrrolidone‐modified GO/NR composite had the smallest fractional free volume and mean square displacement, which led to excellent solvent resistance, and dynamic and physical mechanical properties. This study provides new insights into the design of high‐performance GO/NR composites at the molecular level. © 2022 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

In this work, aramid nanofibers (ANFs)/reduced graphene oxide (ANFs/RGO) film electrodes were prepared by vacuum-assisted filtration, followed by hydroiodic acid reduction. Compared with thermal reduced ANFs/RGO, these as-prepared film electrodes exhibit a combination of mechanical and electrochemical properties with a tensile strength of 184.5 MPa and a volumetric specific capacitance of 134.4 F/cm3 at a current density of 0.125 mA/cm2, respectively. In addition, the film electrodes also show a superior cycle life with 94.6% capacitance retention after 5000 cycles. This kind of free-standing film electrode may have huge potential for flexible energy-storage devices. [ABSTRACT FROM AUTHOR]

Micro structures of viscoelastic materials (VEM) play an important role in their mechanical properties and energy dissipation capacities. This work shows a mathematical modeling of VEMs considering molecular chain-network configurations, and the temperature effects on mechanical properties of VEMs can also be characterized based on the equivalent relationship between temperature and frequency. The Dynamic Thermomechanical Analyzer (DMA) test is carried out to observe dynamic behaviors of the VEM and prove the accuracy of the proposed new mathematical model. The experimental data of viscoelastic damper (VED) are utilized to further verify the correctness of the proposed model with different ambient temperatures. [ABSTRACT FROM AUTHOR]

Conductive hydrogels have highlighted their potential in the fields of electronic skin, soft robotics, and healthcare monitoring, due to their excellent flexibility, tissue-like compliance, and biocompatibility. However, most conductive hydrogels suffer from poor mechanical strength, unsatisfied self-healing properties, and bad temperature tolerance. Herein, we designed a novel ionic organogel based on poly(acrylic acid-co-4-vinylphenylboronic acid) (P(AA-co-VBA)), polyethylene oxide (PEO), tannic acid (TA), and LiCl by simple one-pot radical copolymerization. After elaborately optimizing, the obtained organogel has extremely high mechanical properties (a tensile strength of 0.25 MPa, and an elongation at break of 3200%), good self-healing properties (24 h, 81% self-healing efficiency), and extreme temperature tolerance (from −20 °C to 90 °C). The strain sensor based on the obtained organogel had excellent self-adhesive properties and could closely adhere to the skin to detect temperatures from 0 °C to 42 °C (temperature coefficient of resistance, TCR, at 35 °C is −0.10468 °C−1). The strain sensors also monitor large, subtle body movement within a wide temperature range. It is foreseeable that this ionic organogel will provide new inspiration for the development of flexible strain sensors. [ABSTRACT FROM AUTHOR]

Epoxidized solution‐polymerized styrene butadiene rubber (ESSBR) with different epoxidation degrees was prepared using formic acid as a catalyst. Experimental methods and density function theory calculation confirms that peroxyformic acid preferentially attacks trans‐1,4‐butadiene, and then cis‐1,4‐butadiene, and 1, 2‐butadiene is not epoxidated due to high energy barrier. Two SiO2/graphene oxide hybrids covalently linked with bis‐[3‐(triethoxysilyl)propyl]‐tetrasulfide or 3‐aminopropyltriethoxysilane (KH550) were prepared and named SiO2@TESPT@GO and SiO2@KH550@GO, respectively. The results for ESSBR composites filled by hybrid fillers indicate that the increase of epoxy degree can greatly improve the wet skid resistance while maintaining rolling resistance. Besides, in the case of the same epoxy degree, the rolling resistance of composites using hybrid fillers is lower than that of using SiO2 only. Notably, the SiO2@TESPT@GO/ESSBR composite with high epoxy degree (10.09%) has a good balance between wet skid resistance and low rolling resistance. Molecular dynamics simulation was further employed to perform fixed and cyclic stretching to give the mechanism for mechanical properties. Binding energy and mean square distance illustrate that that as the epoxy degree increases, on the one hand, the strong filler‐matrix interactions will make the movement of ESSBR chains keep up with the strain. On the other hand, the strong filler‐matrix and inter‐chain interactions provide more friction. These two factors lead to an increase in hysteresis loss. Besides, only moderate filler‐matrix interaction is conducive to the improvement of wet skid resistance, and too strong or too weak interaction is unfavorable. [ABSTRACT FROM AUTHOR]