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Wet‐design AC subsea power cables are currently rated up to a maximum voltage of 72.5 kV. These high voltage (HV) cables are cost‐effective alternatives to subsea cables kept dry by a protective lead sheath and exhibit superior properties for dynamic applications. However, several vented water trees, degradation phenomena reducing the cable lifetime, are observed in a HV XLPE insulated cable subjected to wet aging in the laboratory. The water trees initiate from a smooth and clean XLPE insulation/semiconductive screen interface. In this paper, we show that voids in the range 15–150 μm are observed in the conductor screen, 50–320 μm from the water tree inception sites. Degradation of the semiconductive material is observed, in the form of porous regions that connect the voids to the water tree inception sites. NaCl impurities are detected on the void surfaces and in the porous regions. These features are proposed to be the pre‐requisites for the formation of the vented water trees observed in this type of cable. The mechanism responsible for the formation of the void and porous regions in the semiconductive cable screen is discussed based on the observations. [ABSTRACT FROM AUTHOR]

Given the toxicity of wastewater pollutants to both humans and the environment, it is critical to develop a new synthetic membrane with superior permeability and rejection. Herein, a novel asymmetric polyethersulfone (PES) composite filtration membrane was successfully prepared using a simple alternating vacuum‐deposition process with positively charged chitosan and negatively charged cellulose nanofibrils as polycations and polyanions, respectively. As expected, the produced PES composite filtration membranes had a compressed and negatively charged surface, which prevented the anionic dye methyl blue (MB) molecules from infiltrating into the membrane matrix. Consequently, the resulting PES composite filtration membranes exhibited an extremely high MB rejection (99.7%) and a satisfactory flux (37.47 L h−1 m−2 MPa−1). In addition, the composite membrane demonstrated extremely selective removal of anionic dyes in the presence of neutral dyes due to the Donnan effect. Furthermore, the developed PES composite filtration membranes displayed exceptional long‐term stability (99.8% rejection and 36.5 L h−1 m−2 MPa−1 flux after 50 h of filtration) and recycling properties (90.1% flux recovery rate after 3 cycles of running). In conclusion, the PES composite filtration membranes prepared in this study presented great potential in wastewater filtering. [ABSTRACT FROM AUTHOR]

High dielectric constant (ε), thermal conductivity (TC), and breakdown strength (Eb) along with low loss flexible polymeric nanocomposites display multifunctional applications. In this work, to synergistically bolster the TC and Eb while restraining dielectric loss and leakage current in the percolating flaky copper (f‐Cu)/poly(vinylidene fluoride) (PVDF), presenting a giant ε, the core@shell structured f‐Cu@MgO (magnesium oxide) nanosheets were first created via a chemical precipitation method, then incorporated into host PVDF to explore the MgO shell' impact on the TC and dielectric properties of the resulting nanocomposites. The introduced MgO interlayer strengthens the interfacial interactions and significantly mitigates the interfacial mismatch in both ε and conductivity between the f‐Cu and PVDF, resulting in elevated TC and Eb of the f‐Cu@MgO/PVDF in comparison to pristine f‐Cu/PVDF. Furthermore, the insulating MgO interlayer introduces deep traps and inhibits the long‐distance migration of electrons, leading to remarkably suppressed dielectric loss. More importantly, the TC and dielectric properties of nanocomposites can be optimized by tuning the MgO thickness. The fitting results via the Havriliak‐Negami equation theoretically support the MgO shell's suppression effect on charge migration and reveal the underlying polarization mechanism in the nanocomposites. The developed nanocomposites with currently high ε, Eb and TC but low loss, present promising applications in electrical power systems. [ABSTRACT FROM AUTHOR]

Cytarabine, also known as cytosine arabinoside is an anticancer drug, and it is widely used to treat acute myeloid leukemia (AML). But, clinical efficacy of highly hydrophilic cytarabine is often limited due to its rapid degradation and high biodistribution. Hence, this study aims to enhance the anticancer effect of cytarabine with the help of a naturally occurring polyphenol, curcumin. The interaction between cytarabine and curcumin was established by different spectroscopic techniques like UV–Visible, fluorescence, and Fourier transform infrared (FT‐IR). Molecular interactions were also studied using isothermal calorimetric titrations (ITC) followed by theoretical docking. The involvement of the amine group of cytarabine with the interaction of curcumin has been supported by FT‐IR and docking study. However, the major challenge with curcumin is that, in spite of its several medicinal benefits, poor solubility and bioavailability restricts its potential clinical applications. Hence, polymersome‐encapsulated curcumin (PEC) was prepared for the intravenous application. A two‐fold decrease in IC50 value of cytarabine against HeLa cell line was found in presence of encapsulated curcumin. This was justified on the basis of observed reactive oxygen species enhancement in serum in presence of cytarabine and PEC together, determined using absorption spectroscopy. The enhanced affinity of cytarabine toward DNA‐curcumin complex as compared to free DNA, supported by theoretical study, also validates the increased cytotoxicity of cytarabine in presence of PEC. [ABSTRACT FROM AUTHOR]

The network structure and reactivity of suitable restoration agent consisting of silane coupling agents (SCAs) of the brittle walls of a cultural heritage site located underground in a desert area in Egypt were investigated using 1H pulsed nuclear magnetic resonance (pulse NMR). It should possess both high coagulation strength and ductility to ensure that it can withstand an earthquake; it should also contain ethoxy rather than methoxy groups, which generate toxic methanol. The solidification rate for the SCA or oligomer with ethoxy groups was lower than those with methoxy groups; however, the final polycondensates showed the same relaxation time (hardness). The difference spectrum was developed newly to analyze the network structure combined higher strength and ductility. The distribution of crosslinking degree of such polycondensates was narrow, and the amount of lower crosslinking degree was small. On the other hand, the distribution was wide in the polycondensates with ductility but lower strength. From the compression tests of model sand solidified with the restoration agent for both methoxy and ethoxy types showed the superior properties combined higher strength and ductility. The pulse NMR experiment was useful for estimating the solidification rate and the network structure. [ABSTRACT FROM AUTHOR]

This work investigated the composites (PA6/BF) made of basalt fiber (BF) and nylon 6. To improve the interfacial bonding between the fibers and the polymer matrix, and to enhance the thermal and mechanical properties of the composites, polyhedral oligosilsesquioxanes (POSS) with epoxide groups was introduced to modify the surface of BFs using the slurry coating method. It is revealed that the mechanical properties of the composites increased and then decreased with increasing POSS coating. The composite PA6/BF‐POSS3 with BFs modified with a POSS solution of 3.0 wt% showed the best properties. The tensile strength of PA6/BF‐POSS3 was 130.8 MPa, 26.4% higher than that of the PA6/BF and 126.3% higher than that of neat PA6. In addition, PA6/BF‐POSS3 exhibited a 5% weight loss temperature of 417.7, 35.6°C higher than that of PA6/BF. The chemical bonding formed between the amide and epoxide groups, and the hydrogen bonding formed between the amide groups and hydroxyl groups were believed to be the main reasons for the improved interfacial interaction and improved properties. [ABSTRACT FROM AUTHOR]

Exploring new oil absorbing materials with high adsorption rate remains a global challenge. Hydrophobic porous materials with photothermal conversion property are an attractive option to address oil spills. Herein, the organosilicon (hydroxyl‐terminal polydimethylsiloxane) was used to modify polyurethane (PU) foam to endow it good hydrophobic and compressible properties. Meanwhile, polypyrrole (PPy) with photothermal effect was introduced to endow PU foam with excellent photothermal properties. The PPy@Si/PU composite foams can reach 77.1 and 49.6°C under the laser and simulated sunlight (with the intensity of 1 kW/m2), respectively. The raised temperature of PPy@Si/PU foam makes it adaptable to reduce the crude oil's viscosity and improve its oil adsorption rate. The maximum oil adsorption rate of PPy@Si/PU foam can obtain 175% and 145% under the laser and simulated sunlight, respectively. Therefore, the PPy@Si/PU foam possesses effective photic‐driving oil adsorption capacity, which has a good prospect to be an efficient oil spills treatment material. [ABSTRACT FROM AUTHOR]

Molecular dynamic simulation along with experiments was used to study polycarbonate (PC) molecular conformation on composite interfacial properties. The interlaminar shear strength (ILSS) variations of composites with carbon fiber roughness were quite different between sized and unsized carbon fibers, which seem to conflict with the theory that rougher surface is harder to wet. By the results of molecular dynamic simulation, it was found that the conformation of PC molecules through solvent intervention could be higher, which is conducive to the formation of π–π stacking conformation between PC and carbon fibers and benefits the interface interaction, resultantly affecting the ILSS more when the carbon fiber surface area was low. When the specific surface area was high enough, the ILSS gets to a saturation value, because the fracture area changes from the interface to the matrix. It is concluded that the effects of sizing on ILSS varied with carbon fiber surface roughness, and the molecular conformation of the matrix affected by sizing or processing must be considered. Therefore, it is important to enhance the physical interactions with carbon fiber for thermoplastic resin matrixes. [ABSTRACT FROM AUTHOR]

Development of a cost‐effective and environmentally friendly method to treat dye wastewater is of utmost importance. In this experimental study, wastepaper was used as the raw material for the extraction of cellulose nanocrystals to fabricate a nanocomposite membrane with chitosan. During the extraction process, acid hydrolysis (Sulfuric acid) followed by bleaching (hydrogen peroxide) was adopted. To confirm the nano‐range, particle size analysis, and FESEM were performed, which confirmed the presence of particles in the nano‐range ranging from 313.8 to 122.1 nm and FESEM observed results showed transformation of fibrous to rod shaped nanocrystals after acid hydrolysis. After successful nanocomposite fabrication a porous sieved network of membrane was observed and after adsorption successful adhesion of dye molecules over the membrane matrix was also confirmed. FTIR data showed that during adsorption mechanism some of the prominent peaks gets disappeared suggest interaction of dye molecules onto the nanocomposite. The contact angle of 21.0° was observed for the ChNC3 nanocomposite showed super hydrophilic behavior. Tensile strength was also observed in terms of young's modulus, ultimate strength, and elongation at break. The elasticity and stiffness of a material are usually indicated by its young modulus. In AH CNCs and ChNC3, the young modulus was seen to be increasing from 195< 693, respectively. On the other hand, the ultimate strength indicates AH CNCs and ChNC3 and shows a downward trend of 1.56> 0.316, respectively. Furthermore, the potentiality of the nanocomposite membrane was analyzed for Congo red dye in synthetic wastewater prepared in the laboratory. During the batch study, various working parameters were taken such as initial dye solution (20–100 ppm), pH (1–7), contact time (10–60 min), and dosage (0.1–0.5 mg/L). To know about adsorption, Langmuir and Freundlich isotherm were analyzed it was observed that Freundlich isotherm show best fitted modeling with R2 = 0.99, and n = 1.6 showing favorability of the heterogeneous adsorption. To determine the interaction between the adsorbate and adsorbent, pseudo first order and pseudo second order kinetics models were analyzed, and it was observed that chemisorption interaction followed between the adsorbate and adsorbent. Thermodynamic parameters were analyzed, which confirmed the spontaneous and favorable adsorption mechanism. To avoid fouling problems and maintain cost effectiveness, the resulting, nanocomposite membrane was desorbed using an appropriate solvent. After 5 cycles, the desorption rate decreased from 54% to 38%. This developed nanocomposite membrane appears to be effective in effluent waste treatment because of its simple formulation approach. [ABSTRACT FROM AUTHOR]

Since thermally conductive fillers easily aggregate when introduced into polymer matrix, it is essential to apply a modifier to enhance the dispersion of the filler. In current study, the surface of boron nitride (h‐BN) is firstly modified by employing a double modification process and then added into sulfonated polyetheretherketone (SPEEK) to form the composite materials. Four different kinds of samples of double‐modified h‐BN were obtained. Ultimately, the XXX@h‐BN/SPEEK (XXX denoted as modifier, i.e. PDA, VTMS, TEOS, and APS) flexible film with the horizontally oriented XXX@h‐BN was produced by heating the mixture under an external electric field. The test results indicate that the thermally conductive filler PDA@h‐BN (PDA: polydopamine), which was prepared by modifying OH@h‐BN with PDA, loaded into SPEEK, and electrically oriented, shows the best overall performances. With a high tensile strength of 43.24 MPa and good flexibility, PDA@h‐BN/SPEEK flexible film exhibits an in‐plane thermal conductivity of 2.3 Wm−1 K−1 at a filling ratio of 10 wt%. The sample may be bent at a steep angle without breaking down and can recover to original shape bearing its high degree of flexibility. [ABSTRACT FROM AUTHOR]

Poly(butylene adipate‐co‐butylene terephthalate) (PBAT)/thermoplastic starch (TPS) blends were prepared by melt blending. However, the processability and practical application of PBAT/TPS blends are limited by their poor compatibility. To enhance the compatibility between PBAT and TPS, PBAT was functionalized by maleic anhydride (MA) to prepare PBAT‐MA, and then it was employed as a compatibilizer for PBAT/PBAT‐MA/TPS blends. The effects of PBAT‐MA on the tensile properties, rheological properties, morphology, and dynamic mechanics of PBAT/PBAT‐MA/TPS blends were studied in detail. Rheological results revealed that the interaction between PBAT‐MA and TPS enhanced the segment entanglement ability and improved the compatibility of the blends, which enhanced the tensile properties of the blends. Compared with the PBAT/PBAT‐MA/TPS (50/0/50) blend, the tensile strength of the PBAT/PBAT‐MA/TPS (40/10/50) blend increased from 9.2 to 15.8 MPa, and the elongation at break increased from 326.9% to 1017.6%. The dynamic mechanical results showed that the Tg of PBAT and TPS were close to each other after the addition of PBAT‐MA, which confirmed that the compatibility of the blend was improved. This study provides a feasible approach to preparing high‐performance and cost‐effective PBAT/PBAT‐MA/TPS blends while expanding the application prospects of PBAT in the packaging industry and agricultural film. [ABSTRACT FROM AUTHOR]

Oriented polyacrylonitrile (PAN) films were prepared and treated with hot stretching method to obtain higher degree of orientation. The PAN fiber membrane was infiltrated with thermoplastic polyurethane (TPU) to prepare oriented PAN membrane reinforced TPU composite membrane. The tensile properties of the composite material were studied, and the tensile strength, modulus, and toughness all increased with the increase of orientation. The interfacial miscibility between the matrix and nanofibers was observed using Raman spectroscopy, and morphology, properties, and reinforcement mechanism of the composite material were analyzed combining scanning electron microscopy technique. The results indicate as the orientation increases, the compatibility between the matrix and fibers improves, and the mechanical properties of the composite material also improved. [ABSTRACT FROM AUTHOR]

Three ethanolic solutions containing different imidazolium ionic liquids (IL), namely 1‐butyl‐3‐methylimidazolium chloride, 1‐carboxymethyl‐3‐methylimidazolium chloride or 1,3‐dicarboxymethylimidazolium chloride), were used for the surface modification of aramid pulp (AP) (5 wt.% of IL in relation to AP mass) to improve its interfacial interaction with triethylene tetramine‐cured epoxy resin. Composites were prepared by casting with 0.4 phr of AP. Scanning electron microscopy, mechanical tests, isothermal dynamic mechanical analysis (at 1, 10 and 100 Hz), and conventional non‐isothermal analysis were performed. The IL‐modified AP (AP‐IL) presented greater defibrillation and strengthened interaction with the polymeric matrix, minimizing fiber pullout in the mechanical tests. The AP distribution in the epoxy matrix was assessed, and morphological changes were partly responsible for the improvement in the mechanical and dynamical mechanical response of the AP‐IL/epoxy composites. The AP/epoxy composite compatibilized with IL 1‐butyl‐3‐methylimidazolium chloride presented the lowest activation energy and, in turn, the strongest interaction with the epoxy matrix. Normalized DMA curves provided more detailed information on the differences between neat epoxy and the studied composites. [ABSTRACT FROM AUTHOR]

Herein, graphene oxide (GO) and its derivative, reduced GO (rGO) and p‐phenylenediamine (PPD) functionalized GO (GO‐g‐PPD) were first synthesized and selected as dielectric fillers, and then GO/polyimide (PI), rGO/PI, and GO‐g‐PPD/PI dielectric nanocomposites were fabricated through in situ polymerization‐composition strategy. Fourier transform infrared, Ram, and x‐ray diffraction analysis confirmed the success synthesis of rGO and GO‐g‐PPD dielectric fillers. The mechanical properties showed that GO‐g‐PPD/PI nanocomposites exhibited the highest tensile strength and elasticity modulus. TGA analysis revealed that the enhancement of thermal stability by addition of dielectric fillers. The dielectric constant of 2.5 wt.% GO‐g‐PPD/PI nanocomposites reached 25.05, which was 8.55 times that of pure PI (2.93). Energy storage performance tests showed that the energy storage density of GO‐g‐PPD/PI containing 2 wt.% filler reached 0.77 J/cm3, which was 71% higher than pure PI. These findings underscore the potential of GO derivative as a cost‐effective reinforcement for PI dielectric nanocomposites for high‐temperature capacitive energy storage applications. [ABSTRACT FROM AUTHOR]

Water pollution from industrial wastewater and oil spills, which threat marine lives and mankind continually have turned into one of the most severe challenges in worldwide due to the fast development of global industrialization and human activities. Various water‐treatment methods have been developed to solve the problems. However, these processes are often complicated and costly, making them fail to address the complicate water environment. Herein, a visible light‐responsive Au‐BiOCl/TiO2/PAN composite membrane with hydrophilic surface was prepared by combing electrospinning with solvothermal method. The composite membranes can efficiently separate emulsions with the highest flux of 50.16 L m−2 h−1 and oil/water mixtures (the highest flux was 4777.07 L m−2 h−1 bar−1). Moreover, the membranes can rapidly degrade antibiotics with an excellent degradation rate (95.70% in 60 min) under the visible light. Additionally, they can simultaneously degrade organic dye and separate oil/water emulsions under a gravity condition. It is expected that composite membranes will be an attractive candidate for complex wastewater treatment. [ABSTRACT FROM AUTHOR]

Core‐Shell (CS) polymeric particles have attracted great interest due to their high mechanical, thermal, and chemical stability and their surface properties. In this study, functionalizable CS poly(propylene/styrene)/poly(acrylonitrile) (PP/PS/PAN) particles were prepared through heterogeneous polymerizations in a batch reactor. Commercial PP particles and PP/PS particles (prepared by seeded suspension polymerization of styrene (Sty) on PP spheres) were applied as core components of the final structure, while the shell was prepared through acrylonitrile dispersion polymerization. The degree of swelling of the core particles by Sty played an important role for the adhesion of the PAN shell, which for PP particles was 24 wt%, whereas for PP/PS hybrid particles it was 57 wt%. The particles (PP/PS and CS) were characterized through image analysis, revealing a uniform and smooth surface for PP/PS spheres and a uniform porous shell for CS particles. Particle size distributions, thermal degradation, chemical structures, degrees of crystallinity, and textural properties were also evaluated. The PAN shell adhered to the PP/PS particles without forming a copolymer, and the CS particles formed by a PP/PS core and PAN shell had sizes of 4.54 ± 1.24 mm, specific area of 2.70 m2g−1 and PAN content of 15.98 ± 0.82% (m/m) of total particles. [ABSTRACT FROM AUTHOR]

This work describes the effect of functionalized silica, treated with organosilane (γ‐methacryloxypropyltrimethoxysilane), on the wettability loss of polypropylene (PP) film when exposed to surface oxidization treatment by atmospheric air plasma. The observed wettability loss results from the spontaneous process within the polymer matrix, which reduces surface energy, causing oxidized polymer molecules to move toward the bulk of the film. The effect of silica's functionalization on the initial wettability of oxidized PP film and its loss on storage time is measured by contact angle. Elemental analysis of the modified silica, employing acid catalytic processes, reveals the highest functionalization yield. Silicon nuclear magnetic resonance shows that the post‐condensation process negatively affects structures formed by the organosilane, eliminating three‐dimensional bonds and reverting it to its original and hydrolyzed state. The solvent extraction process and elemental analysis confirm that the concentration of organosilane in the chemically bonded layer, which was around 9 wt%, is not influenced by the post‐condensation treatment. Notably, silica functionalized with the highest concentration of organosilane has significantly improved initial wettability when oxidative treatment occurs within a shorter residence time (30 s), which achieved a contact angle of 53.8° against 59.1° for the film with untreated silica. However, the wettability loss rate of the materials remains unaffected by the presence of functionalized silica. [ABSTRACT FROM AUTHOR]

Laser polishing technique is one of the most effective post‐processing methods for 3D‐printed Polylactic acid (PLA) substrates and has gained significant interest of scientific research community in past few years. This paper aims to investigate the effect of fill density, laser power, and scanning speed on the polishing responses of 3D‐printed PLA substrates. These include surface roughness, mass ablation rate, and optical transmittance of PLA substrates printed using the fused deposition modeling technique. The optical transmittance was measured using Fourier‐transform infrared spectroscopy technique and surfaces were characterized using scanning electron microscope, and optical microscope. Minimum surface roughness of 1.04 μm was achieved at 5% laser power and 55% fill density constituting a decrease of 61.8% from unpolished PLA (2.735 μm). The lowest mass ablation rate (0.015 μg/pulse) was observed for the specimens with 40% infill density. Higher scanning speed enhanced the molecular bonding in PLA‐55 specimen indicated by increased peak transmittance ratios of CH bonds at stretching (1.021) and bending modes (1.045). [ABSTRACT FROM AUTHOR]

The non‐biodegradability of Ethylene‐Propylene Side‐by‐Side (ES) fibers has led to significant environmental pollution from waste sanitary products, thereby posing a severe challenge to the environment. Replacing traditional non‐biodegradable materials with biodegradable polymeric materials is the most effective method to achieve a green environment. In this study, core‐sheath fibers composed of biodegradable poly (butylene adipate‐co‐terephthalate) (PBAT) as the sheath layer and polylactic acid (PLA) as the core layer were fabricated. The effects of different viscosity ratios and the composite ratios of sheath and core on the structure and performance of the resultant core‐sheath fibers were investigated in detail. The results showed that when the PBAT/PLA composite ratio is 50:50 and the viscosity ratio range from 0.8 to 1.43, the PBAT/PLA core‐sheath composite fibers exhibit good spinnability and a complete core‐sheath structure, with their tensile properties comparable to those of PP/PE core‐sheath composite fibers. Further research found that when the viscosity ratio was 1.00 and the PLA component content in the PBAT/PLA composite fibers increased from 40% to 60%, the fibers still maintained good spinnability and a complete core‐sheath structure. In addition, when the PBAT/PLA composite ratio was 60:40, after 120 days of biodegradation, its strength retention rate was only 35.2%. [ABSTRACT FROM AUTHOR]

Polyphenylene sulfide sulfone (PPSS) was synthesized by one-step method and utilized as a sizing agent for carbon fibers. The effects of various monomer ratios, reaction time, and reaction temperature were investigated on the molecular weight of PPSS. The thermal analysis revealed that the product PPSS exhibited a glass transition temperature exceeding 215.5°C, indicating exceptional thermal stability. After PPSS sizing treatment, the grooves on the surface of carbon fibers were filled, resulting in a substantial enhancement of the micro interface properties. The surface energy was increased by 8.2%, while the maximum weight loss temperature was 27.8% higher than that of the commercial carbon fiber. The tensile strength of the carbon fiber after heat treatment reached 2196 MPa, representing a 45.9% increase over that of the commercial carbon fiber. [ABSTRACT FROM AUTHOR]

The influence of material surface microstructure on interface properties is crucial for the preparation and development of special functional materials. In this paper, polydimethylsiloxane‐based superhydrophobic surfaces of varying roughness and surface energy are prepared using the template method and a spraying technique, and the effect of surface microstructure on lateral friction is studied using a lateral friction detection system. The experimental results indicate that as the surface roughness of a sample decreases, it is observed that the water droplets transition from a Cassie state to a Wenzel state. When the roughness changes from 4.619 μm, reduce to 3.512 μm, the maximum static friction force increases from 33.59 μN increased to 51.52 μN. The lateral sliding friction force ranges from 15.87 ± 1.9 μN increases to 40.91 ± 1.2 μN. For a given surface roughness, when the surface energy is reduced, the water droplets on the surface can be seen to transition from a Wenzel state to a Cassie state, the maximum static friction force increases from 19.32 μN dropped to 9.23 μN, and the lateral sliding friction force increases from 15.26 ± 1.6 μN dropped to 3.47 ± 2.1 μN. However, this behavior is distinct from that observed when changing the roughness of the sample. Studying the influence of the surface microstructure on the lateral friction force observed at a solid–liquid interface can provide important insights into novel geometries that may be used in new, advanced functional surfaces. [ABSTRACT FROM AUTHOR]

In our prior paper, surface micelles with the core‐shell‐petal structure of the double hydrophilic block copolymer poly(N‐isopropylacrylamide)‐block‐poly[oligo(ethylene glycol) acrylate] (PNIPAM‐b‐POEGA) were successfully evaluated. In this work, ionic strength (under acidic conditions) and anion‐specificity effects (under neutral conditions) on the aggregation behavior of PNIPAM‐b‐POEGA at the air/water interface and the morphologies of its Langmuir–Blodgett (LB) films were systematically studied. Under acidic conditions, the salting‐out effect prevails over the electrostatic shielding effect, and the amide group shells with a slight protonation degree are covered up by the large POEGA petals. Under neutral conditions, the stretching degrees of POEGA blocks at low/moderate salt concentrations are close. At high salt concentrations, the isotherms gradually shift to large molecular areas in the order of the NaCl, Na2SO4, NaNO3, and NaSCN cases. The hysteresis degrees of the monolayers increase with the increase of salt concentrations due to the gradually increased interfacial stretching degree and compression‐induced underwater solubility of POEGA blocks. All the initial LB films of PNIPAM‐b‐POEGA exhibit isolated circular micelles with small cores. Upon compression, the LB films exhibit slightly large micelles because of the possible coalescence of some neighboring cores. [ABSTRACT FROM AUTHOR]

Starch is an environmentally friendly, renewable, green resource and an ideal alternative to polymers from petroleum resources. The preparation of high‐performance poly (butylene adipate‐co‐terephthalate) (PBAT)/corn starch composite materials is of significant importance for saving production costs and expanding the application fields of PBAT plastics. This study employed novel processing techniques such as melt blending and injection molding to fabricate PBAT/corn starch composite materials with polyurethane prepolymer (PCLPU) as a compatibilizer. The impact of varying polyurethane prepolymer concentrations on the composite material's structure, mechanical properties, morphology, thermal behavior, and water absorption was scrutinized. Mechanical performance testing showed that compared to the composite material without PCLPU (P90CS10), adding 5% PCLPU can increase the material's elongation at break from 350.2% to 359.0% and the tensile strength from 12.9 to 19.8 MPa. Scanning electron microscopy, thermogravimetric analysis, and water absorption results indicate that the composite material with the addition of the PCLPU compatibilizer has better compatibility, thermal stability, and water resistance than P90CS10. Additionally, the prepared composite material could be successfully blown into a thin film, further enriching the application of the composite material. Highlights: A special interface structure was prepared to increase the compatibility of the poly (butylene adipate‐co‐terephthalate)/corn starch composite.Both the strength and the flexibility of the composite were successfully improved.The processing method through which modification was conducted in the melt was convenient, green, and effective.The prepared composite material has potential application value, and the processing method of the composite material is easy to transfer to industrial production. [ABSTRACT FROM AUTHOR]

Sticking between the thermoplastic polymer and metal tool is a crucial issue, as it determines whether the manufactured part can be ejected from the metal mold. Polyimide (PI) release films have been widely used in the processing of fiber‐reinforced thermoplastic polymer composites. Compared with other release mediums such as release agents, PI release film has a higher release efficiency. However, the underlying release mechanism is still not well understood which is essential to improve their performance further and reduce the cost. In this paper, poly(ether ketone ketone) (PEKK) polymer was melted and cooled down between two PI films. The surface morphologies and chemical compositions of the PI film and PEKK were characterized both before and after release using atomic force microscope, x‐ray photoelectron spectroscopy, contact angle measurements, and confocal microscopy. It showed that a thin PI layer was transferred from the PI release film to the PEKK surface during the release process. Based on these experimental results, a modified boundary layer mechanism is proposed as a hypothesis to describe the release mechanism of PI films. Our results give a fundamental understanding of how PI film works for the release of thermoplastics with high processing temperatures and may help to improve the performance and reduce the costs of existing PI films and may give guidance to the design of new release media. [ABSTRACT FROM AUTHOR]

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A new simplified low temperature deposition method to manufacture flexible transparent conductive electrodes (FTCE) based on conductive polymer composite filled with silver nanowires (AgNWs) was investigated. Polyurethane/AgNWs composite was deposed on a poly(ethylene terephthalate) substrate as a conductive paint in a thin layer lower than 2 μm. The high aspect ratio nanowires influence on the electrical behavior is followed with surface resistivity and optical transparency experiments. The best compromise was obtained with a conductive layer filled with 2.84 vol.% of AgNWs; it exhibits a surface resistivity of 143 Ω/sq with 73% in transmittance. These transparent conductive composites processing in one step with good touching manipulation resistance demonstrate the real interest for this kind of FTCEs technology without indium tin oxide. [ABSTRACT FROM AUTHOR]

To clarify the formation mechanism of front frame‐type morphology, the stringiness of crosslinked random copolymers of poly(n‐butyl acrylate‐acrylic acid) during a 180° peel test with a constant tensile rate was examined for various crosslinker contents and rates using a quartz adherend. Cohesive failure occurred for lower crosslinker content and rate, whereas interfacial failure with sawtooth‐type stringiness without a frame was observed for higher crosslinker content and rate. Front frame‐type stringiness was formed at the boundary of cohesive and interfacial failures. To clarify the formation mechanism, observation was conducted from the start of peel test until the equilibrium state. The sawtooth‐type stringiness with branches first formed at the tip. The adjoining branches were connected and the 2D frame was formed only on the adherend surface. The formed 2D frame developed toward the 3D walls and the front frame‐type was then completed. This is caused by the surface tension that acts to restrain the increase in the surface area. However, the surface area of the front frame‐type morphology was larger than the no frame‐type. The larger absorption of peeling stress by the formation of this morphology is expected to contribute to peel strength improvement. [ABSTRACT FROM AUTHOR]

A surface in contact with the isotropic phase of a passive liquid crystal can induce nematic order over distances that range from microscopic to macroscopic when the nematic-isotropic interface undergoes an orientational-wetting transition. If the nematic is active, what happens to the interface? Does it propagate and, if it does, is its structure different from the passive one? In this paper, we address these questions. We investigate how the active nematic-isotropic interface is affected by the anchoring strength of the surface, the bulk ordering field and the activity. We find that while passive interfaces are one-dimensional the active ones exhibit two dynamical regimes: a passive-like regime and a propagating regime where the interfaces propagate until the entire domain is active nematic. Active interfaces break the translational symmetry within the interfacial plane above a threshold activity, where the active nematic fluctuations, which are ultimately responsible for the emergence of an active turbulent nematic phase, drive non-steady dynamical interfacial regimes.

The evolution of fault friction during the interseismic period affects the mechanics of a future earthquake on the same fault patch. Frictional aging has been previously tied to time‐dependent contact area growth through observations made on rock analogs. However, our understanding of the processes that control frictional aging is limited and is dependent on experiments that explore only numerous mechanisms. We conduct slide‐hold‐slide experiments with a dual‐axis nanoindenter on single‐crystal surfaces of quartz and calcite. Our results show that frictional aging in diamond‐quartz contacts is independent of time and contact area, in stark contradiction to past experiments done on quartz‐quartz contacts in rocks. Diamond‐calcite contacts show modest frictional aging, but still well below previous reported values from calcite‐calcite contacts. These results suggest that frictional aging of like‐on‐like minerals may be of chemical origin, as suggested in recent studies with atomic force microscopy and molecular dynamics simulations. Plain Language Summary: Frictional aging is the process of re‐strengthening of frictional contacts, either by an increase in contact area or by an increase in shear strength of the contact. Aging is important in the earthquake cycle where it affects the mechanical response of a future earthquake. Frictional aging has been studied extensively in the past through slide‐hold‐slide (SHS) experiments in rocks where the contact is slid at a constant velocity, then held stationary for a predetermined 'hold time', after which sliding resumes. These experiments show that the static friction measured at the end of the hold, as sliding commences, scales with the logarithm of hold time. This result is commonly interpreted as being due to contact area growth as observed in rock‐analogue materials (such as polymers). We conducted SHS experiments with a nanoindenter capable of inducing frictional sliding of a diamond tip over a substrate while continuously monitoring contact area. Experiments performed on single crystals of quartz and calcite show no or minimal frictional aging even though contact area grows with the logarithm of hold time. Our results suggest that frictional aging of these mineral contacts is due to a chemical mechanism and not explicitly due to contact area growth. Key Points: Diamond‐quartz and diamond‐calcite contacts show time‐dependent contact area growthQuartz surfaces do not exhibit frictional aging, suggesting that aging is of chemical originCalcite surfaces exhibit modest frictional aging with contact area, but significantly lower than in experiments on calcite rocks [ABSTRACT FROM AUTHOR]

Advancement in the understanding of fundamental aspects of Secondary Ion Mass Spectrometry (SIMS) has made this technique to be extremely powerful for quantitative materials analysis. The secondary ion emission process is a complex phenomenon involving various mechanisms to understand the mechanism. Among the existing mechanisms, the “electron-tunneling model” is the most accepted concept in the understanding of ionization probability for positive and negative ions. This model essentially concerns the survival probability of an ion emitted from the surface. As the intensity of secondary ions of a certain element depends strongly on the efficiency of ionization of a sputtered atom or molecule, the “local surface chemistry” plays a significant role in the secondary ion emission. This is purported as the “Matrix Effect” in SIMS, making the technique extremely challenging for quantification of materials in spite of the fact that it has the highest detection sensitivity (

Abstract The evolution of fault friction during the interseismic period affects the mechanics of a future earthquake on the same fault patch. Frictional aging has been previously tied to time‐dependent contact area growth through observations made on rock analogs. However, our understanding of the processes that control frictional aging is limited and is dependent on experiments that explore only numerous mechanisms. We conduct slide‐hold‐slide experiments with a dual‐axis nanoindenter on single‐crystal surfaces of quartz and calcite. Our results show that frictional aging in diamond‐quartz contacts is independent of time and contact area, in stark contradiction to past experiments done on quartz‐quartz contacts in rocks. Diamond‐calcite contacts show modest frictional aging, but still well below previous reported values from calcite‐calcite contacts. These results suggest that frictional aging of like‐on‐like minerals may be of chemical origin, as suggested in recent studies with atomic force microscopy and molecular dynamics simulations.

Polydimethylsiloxanes (PDMS) foam as one of next-generation polymer foam materials shows poor surface adhesion and limited functionality, which greatly restricts its potential applications. Fabrication of advanced PDMS foam materials with multiple functionalities remains a critical challenge. In this study, unprecedented self-adhesive PDMS foam materials are reported with worm-like rough structure and reactive groups for fabricating multifunctional PDMS foam nanocomposites decorated with MXene/cellulose nanofiber (MXene/CNF) interconnected network by a facile silicone foaming and dip-coating strategy followed by silane surface modification. Interestingly, such self-adhesive PDMS foam produces strong interfacial adhesion with the hybrid MXene/CNF nano-coatings. Consequently, the optimized PDMS foam nanocomposites have excellent surface super-hydrophobicity (water contact angle of ≈159o), tunable electrical conductivity (from 10-8 to 10 S m-1), stable compressive cyclic reliability in both wide-temperature range (from -20 to 200 °C) and complex environments (acid, sodium, and alkali conditions), outstanding flame resistance (LOI value of >27% and low smoke production rate), good thermal insulating performance and reliable strain sensing in various stress modes and complex environmental conditions. It provides a new route for the rational design and development of advanced PDMS foam nanocomposites with versatile multifunctionalities for various promising applications such as intelligent healthcare monitoring and fire-safe thermal insulation. [ABSTRACT FROM AUTHOR]

Polyvinylidene fluoride (PVDF) membranes have been widely applied in the separation of various organic matters owing to their excellent properties. However, they possess low wettability and undergo fouling because of the hydrophobic nature of PVDF. In this study, poly (2‐hydroxyethyl methacrylate) (PHEMA) and poly (sulfobetaine methacrylate) (PSBMA) were co‐introduced to modify the highly hydrophobic PVDF membrane surface via UV photo‐irradiation. Facile UV photo‐grafting was performed by irradiating the pristine PVDF membrane immersed in a PHEMA/PSBMA mixture solution with UV light for 5 min. The performance of the as‐prepared PHEMA/PSBMA‐grafted membrane was compared with that of membranes modified with solely PHEMA or PSBMA. The hydroxyl and zwitterionic groups of the grafted membranes enhanced wettability and increased flux. A tightly bound water layer was formed because of the enhanced wettability, significantly suppressing protein adsorption. The initial flux of bovine serum albumin (BSA) solution through the PHEMA/PSBMA‐grafted membrane was 2861 LMH, which was 3.1 times higher than that obtained by the pristine PVDF membrane. Furthermore, the flux decline of the modified membrane caused by BSA fouling was 49% lower than that of the pristine PVDF membrane. Finally, the PHEMA/PSBMA‐grafted PVDF membrane showed antifouling properties after three BSA filtration cycles. [ABSTRACT FROM AUTHOR]

For a probe tack test for a pressure‐sensitive adhesive (PSA) under the conditions of light contact pressure and short contact time, probes with shapes and surface roughnesses suitable to achieve better wettability were investigated. A smooth, polished probe that became slightly convex at its center was found to be superior to flat‐ended. High surface roughness decreased tack. Debonding observations showed that fibrillation started from the probe edge and extended to the center. The fibril grew, without peeling, until the peak of the force–displacement curve was reached. After the peak, the fibril growth and peeling advanced simultaneously. The fibrillation was important to tack development. The test conditions necessary to observe the deformation behavior of PSA tape with sufficient interfacial adhesion were investigated. The system was preheated at 60°C for 1 h after the probe and PSA tape contacted each other, and was then cooled. The PSA performance of crosslinked random copolymers poly(n‐butyl acrylate‐acrylic acid) (A) and poly(2‐ethylhexyl acrylate‐acrylic acid) (B) were compared. A shoulder formed by fibrillation after the peak in the force–displacement curve was observed only for B. Copolymer B exhibited better interfacial adhesion and deformability. The preheating method was found to be useful for characterizing PSAs. [ABSTRACT FROM AUTHOR]

The properties of carbon fiber (CF) reinforced thermoplastic resin composites depend on the physical and chemical interaction between the fibers and the resins. However, surface oxidation is not always necessary. In this study, the interaction between CF and Polyphenylene sulfide (PPS) is enhanced by using an emulsion of reactive sulfur to treat the CF surface. The interlaminar shear strength (ILSS) of CF/PPS composites is experimentally investigated and found to be up to 79.7 MPa, an increase of 36.1% compared to the untreated CF. The enhancement mechanism of the modification method established is inferred. Scanning electron microscope (SEM) and X‐ray photoelectron spectroscopy (XPS) results showed that sulfur etching on the surface of CF generated new functional groups, which improved the interfacial effect, and tightened the bond between CF and PPS. This indicates that sulfur treatment along with sizing must be a simpler method than surface oxidation to promote the interfacial bonding between CF and PPS. [ABSTRACT FROM AUTHOR]

Suitable reaction cells are critical for operando near ambient pressure (NAP) soft x-ray photoelectron spectroscopy (XPS) and near-edge x-ray absorption fine structure (NEXAFS) studies. They enable tracking the chemical state and structural properties of catalytically active materials under realistic reaction conditions, and thus allow a better understanding of charge transfer at the liquid–solid interface, activation of reactant molecules, and surface intermediate species. In order to facilitate such studies, we have developed a top-side illuminated operando spectro-electrochemical flow cell for synchrotron-based NAP-XPS/-NEXAFS studies. Our modular design uses a non-metal (PEEK) body, and replaceable membranes which can be either of x-ray transparent silicon nitride (SiN _x ) or of water permeable polymer membrane materials (e.g. Nafion ^TM ). The design allows rapid sample exchange and simultaneous measurements of total electron yield, Auger electron yield and fluorescence-yield. The developed system is highly modular and can be used in the laboratory or directly at the beamline for operando XPS/ x-ray absorption spectroscopy investigations of surfaces and interfaces. We present examples to demonstrate the capabilities of the flow cell. These include an operando NEXAFS study of the Cu-redox chemistry using a SiN _x /Ti-Au/Cu working electrode assembly (WEA) and a NAP-XPS/-NEXAFS study of water adsorption on a Nafion ^TM polymer membrane based WEA (Nafion ^TM /C/IrO _x catalyst). More importantly, the spectro-electrochemical flow cell is available for user community of B07 beamlines at Diamond Light Source.

Poly(3,4‐ethylene dioxythiophene) (PEDOT) is a promising electrochromic material in many practical application, such as smart windows and displays. However, there are still difficulties in currently realizing green manufacturing, high coloration efficiency, and rapid response. Herein, in‐situ electrochemical polymerization of PEDOT:PSS/Reline films was suggested in aqueous solution. Deep eutectic solvents (DES) composed of choline chloride and urea (Reline) were employed as green solvents in reaction system and used as dopants for the PEDOT:PSS. The as‐prepared PEDOT:PSS/Reline films exhibited remarkable electrochromic properties, including great ion diffusion coefficient, fast reaction time (coloration response time was 1.4 s), prominent transmittance modulation (38%), high coloration efficiency (223 cm2/C) and excellent cyclic stability. Impressively, doping of Reline cannot only provide a green polymerization environment, but also significantly boost the electrochromic properties. [ABSTRACT FROM AUTHOR]

With the miniaturization and integration of electronics into more powerful but smaller functional devices, major challenges arise. One of them is to efficiently dissipate the significant amount of thermal energy produced by these electronic devices. This requires interface materials with good thermal management properties. Reduced graphene oxide has attracted a lot of interest in this area due to its good thermal conductivity, similar with those of pristine graphene. In this work, polymethylmethacrylate/reduced graphene oxide (PMMA/RGO) composite thin films have been generated by drop casting mixtures of PMMA solutions and RGO suspensions, all prepared in N,N‐dimethylformamide (DMF) solvent. Raman, SEM and AFM investigations confirmed that homogenous PMMA/RGO composite thin films have been obtained, with RGO being uniformly distributed in the blending. Further measurements demonstrated that the thermal conductivity of RGO/PMMA composites increased with the concentration of RGO in the polymeric mixture: for the highest RGO content, the thermal conductivity increased by 210%, with no important modifications of electrical resistivity. These results are very promising for the development of new thermal interface materials based on PMMA/RGO composites to be used, for instance, in automotive industry. [ABSTRACT FROM AUTHOR]

Multi‐walled carbon nanotubes (MWCNT)/carbon fiber fabric multiscale hybrid materials were prepared by grafting MWCNT on carbon fabric surface via heating grafted method to improve the mechanical and tribological properties of phenolic resin composites. Field emission scanning electron microscopy, Raman spectrometer, and X‐ray photoelectron spectroscopy were used to analyze the surface properties of carbon fiber. The results shown that the tensile strength of composites modified by 0.15 wt% MWCNT was 38% higher than that of unmodified composites. The wear rates decreased from 3.31 × 10−14 m3 (N·m)−1 for unmodified composites to 0.68 × 10−14 m3 (N·m)−1 for 0.15 wt% MWCNT reinforced composites. The reason was that the uniformly distributed MWCNT could increase interface interaction and mechanical interlocking between carbon fiber fabric and resin matrix. [ABSTRACT FROM AUTHOR]

A weak interface is formed between injected plastic and substrate during the injection over‐molding process. This study investigated the effects of mold temperature and melt temperature on the bond strength of injection over‐molded components, which were produced by injecting short carbon fiber reinforced polyether‐ether‐ketone (SCF/PEEK) onto the surface of woven carbon fiber reinforced PEEK (WCF/PEEK) laminate substrate. The results show that the interfacial laminar shear strength (ILSS) increases significantly from 15.8 to 50.0 MPa as the mold temperature raises from 190 to 260°C. The ILSS increases first and then decreases with melt temperature raises from 380 to 420°C, achieving a maximum value of 44.4 MPa at 410°C melt temperature. Crystallinity analysis and microscopic observations indicate different bonding modes are formed at the interface. The matrix tangling appears in the matrix enrichment area, interlocking, and tangling appear in the pits and weak tangling and cracks occur on the fiber surface. The mold temperature affects the ILSS by changing the crystallization property and the connection mode in the interface, while the melt temperature affects the ILSS by changing the area of the matrix entanglement. The relationship between the process conditions—interfacial microstructure—interfacial mechanical performance was discussed. [ABSTRACT FROM AUTHOR]

The optimal restoration agent for the brittle walls of Idout's tomb built 4400 years ago in Saqqara, Egypt, which is located underground in a desert area, was investigated. From x‐ray diffraction analysis of the sand collected near the tomb, the main ingredient is silica. Alkoxysilane and its oligomer are used because its alkoxy groups can react readily with silica. The compressive test of solidified model sand its main component is silica was done. The increase of both molecular weight of oligomer and the content of oligomer with higher molecular weight effectively developed the compressive force. When an earthquake occurs, it is desirable that the reinforced wall will be crushed in ductility. The addition of di‐alkoxy type alkoxysilane to oligomers changed the failure mode from brittle to ductile, because the network becomes looser. When a moderate quantity of di‐alkoxy type is added to oligomers, the solidified model sand deforms with greater displacement, while maintaining a high compressive force. From scanning electron microscopic observation of fractured solidified specimen, alkoxysilane was making the sand particles connect as a binder. Many cracks were clearly observed in the binder layer. Whereas, the formed crack was far smaller for di‐alkoxy added system. [ABSTRACT FROM AUTHOR]

With the current situation of high‐energy consumption and high pollution in the textile industry, developing an eco‐friendly and universal dyeing technology is urgently required. Towards this goal, in this study, the dyeing technology with room temperature, salt‐free, zero release, and rapid cycle dyeing for 20 min was realized using a polymer of catechol and polyethyleneimine as a dye. The dyed fabrics exhibited washing, rubbing, and perspiration fastness characteristics for practical needs, mainly attributing to the hydrogen bonding and π–π interaction between the dye molecules and the fabrics. Benefiting from the unique dyeing technology, the dyed fabrics show excellent leveling properties and adjustable chromaticity. Importantly, the mussel‐inspired coating strategies are universally applicable, so the dyeing technology can be applied to various fabrics. Consequently, the environmentally friendly dyeing process based on low‐cost catecholamine polymers as a dye will have a broad application prospect in the printing and dyeing industry. Moreover, the antibacterial tests showed that dyed cotton cloth, mulberry silk, and polyester fabrics all have favorable antibacterial properties, especially dyed mulberry silk fabrics have a greater than 90% bacterial reduction rate for both Escherichia coli and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Silver nanoparticles functionalized poly‐p‐phenylene terephthamide (PPTA) fiber was fabricated through the electroless plating method. To facilitate the efficient deposition of silver nanoparticles, the PPTA fiber surface was modified by using dopamine and γ‐methacryloxypropyl trimethoxy silane (MPTES). Various techniques including scanning electron microscope (SEM), X‐ray photoelectron spectroscopy (XPS) and X‐ray diffraction (XRD) were used to characterize the surface morphology and chemical composition of surface modified and silver‐plated PPTA fibers. The silver‐plated PPTA fiber showed a surface resistance of 0.53 Ω over a length of 1 cm with reliable coating fastness under ultrasonic washing and high temperature treatment. Furthermore, the silver‐plated PPTA fiber exhibited antibacterial resistance against Escherichia coli and Staphylococcus aureus, as well as good electrical heating performance with surface temperature of 100.4°C at a voltage of 4.5 V. [ABSTRACT FROM AUTHOR]

The carbon fiber/epoxy resin (CF/EP) composites have been prepared using CF and the diglycidyl ether of bisphenol‐A (DGEBA) matrix, modified by a new epoxy‐terminated hyperbranched polyether sulfone (EHPES). Compared with CF/DGEBA composite, the modified CF/EHPES composites achieve excellent performances. The tensile strength, modulus, and elongation at break are increased by 19.1%, 7.9%, and 66.7%, respectively. The results are mainly caused by the strong interfacial properties, the interfacial shear strength (IFSS) of CF/7% EHPES composite is increased by 20.7%. Many crosslinking points enhance the mechanical interlocking between the DGEBA/EHPES matrix and CF surface. The strengthened chemical bonding promotes the formation of a higher density crosslinking network. This study provides a strategy for the domestication of large diameter wind turbine blades. [ABSTRACT FROM AUTHOR]

Shape memory materials have received great scientific attention for engineering applications because of their unique memory recoverable properties. In this study, high toughness and strong damping shape memory epoxy asphalt composites (SMEAC) were prepared, which can be widely used in the fields of bridge self‐repairing expansion joints, crack sealants, vibration control, and damping devices in earthquake engineering. The mechanical properties, shape memory properties, and shape memory mechanism of SMEAC were analyzed by macroscopic and microscopic tests. The direct tensile tests showed that SMEAC has excellent toughness and strength. The temperature sweep test revealed that SMEAC has good damping properties. The shape memory recovery performance of SMEAC was analyzed by thermomechanical analyzer, and X‐ray diffraction showed the change of full width at half maxima in SMEAC before and after deformation at microscopic level. Infrared spectroscopy and fluorescence microscopy indicated that the asphalt phase in SMEAC could participate in the curing reaction, which enhanced the miscibility between the asphalt phase and the epoxy resin phase. Finally, the curing mechanism of epoxy asphalt composites was derived by combining infrared spectral analysis. This work provides a theoretical reference for developing new shape memory materials and open up a new application mode for epoxy asphalt. [ABSTRACT FROM AUTHOR]

To better understand the damage failure mechanism of ultra‐high molecular weight polyethylene (UHMWPE) in engineering application environments, a study was conducted to explore the effect of rotation speed on its abrasive wear performance in lubricant media containing abrasive particles, especially in comparison to the water. The wear mechanism was analyzed by friction coefficient and wear behavior. The results show that UHMWPE has excellent tribological properties in the water and is seriously worn in the abrasive environment. Under the condition of abrasive wear, there exists a critical rotation speed (360 r/min) leading to a shift in the wear mechanism of UHMWPE and obtaining the lowest wear rate of about 8.49 × 10−6 mm3/N•m. At below critical rotation speed, three‐body abrasive wear and adhesive wear mainly occur in UHMWPE; And at above critical rotation speed, the wear mechanism is mainly the plowing effect of particles on the material, and the furrow width can reach 40 μm. It is believed that this study can help to improve the understanding of the wear mechanism of UHMWPE, which can support the enhancement modification of the material and the application in complex environment. [ABSTRACT FROM AUTHOR]

Developing efficient, stable, and cost-effective electrocatalysts is crucial for large-scale industrial water electrolysis hydrogen production. In this study, a-Cu 2 Se@Cu 3 P/CF heterostructure electrode was constructed by form amorphous Cu 2 Se on Cu 3 P nanowire array, which proved the electrode efficient contact with electrolyte, enhanced electron transfer in the electrode with abundant pathway and active sites. Ultimately, these enhancements significantly improved the HER performance of the a-Cu 2 Se@Cu 3 P/CF electrode. In alkaline electrolyte, the a-Cu 2 Se@Cu 3 P/CF electrode exhibits overpotential as 99 mV@10 mA cm−2 and Tafel slope as 79 mV/dec. The a-Cu 2 Se@Cu 3 P/CF electrode is capable of maintaining a stable potential (− 1.17 V, − 1.21 V, − 1.30 V, − 1.37 V, − 1.50 V) for a long duration (10 h) at different current densities (10 mA cm−2, 20 mA cm−2, 50 mA cm−2, 100 mA cm−2, 200 mA cm−2). Additionally, at a current density of 100 mA cm−2 and 200 mA cm−2, the catalytic performance has been slightly enhanced approximately 1.5 % and 1.8 % at the end of 10 h duration test. This demonstrated the excellent stability of the a-Cu 2 Se@Cu 3 P/CF electrocatalyst, showcasing its potential for practical applications in hydrogen production. • We fit the values of hydrogen adsorption free energy and overpotential from recent heterostructure reports into a function. • The a-Cu 2 Se@Cu 3 P/CF electrode with a-Cu 2 Se@Cu 3 P heterostructure exhibits a lower overpotential than Cu 2 Se-Cu 3 P/CF electrode. • The strong interaction between a-Cu 2 Se and Cu 3 P improved the electronic structure near the heterojunction interface. • The a-Cu 2 Se@Cu 3 P/CF electrode exhibits excellent stability and slightly improved in performance at high current density. [ABSTRACT FROM AUTHOR]