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Biocomposite materials made of natural plant fibers are becoming a viable alternative to the use of synthetic ones such as glass fibers, thanks to many economic, ecological, and technical benefits. However, their massive use in the industry requires optimal control of their mechanical performances, which constitutes a real scientific issue to be overcome. Indeed, biocomposites suffer from an important variability in their mechanical properties because of their multiscale structure, natural growth conditions, and various processing parameters, in addition to eventual chemical treatments. Biocomposites are also highly sensitive to the surrounding environment in terms of humidity and temperature because of the hydrophilic properties of natural plant fibers. In this context, this Perspective aims to provide a critical look at the influence of the main factors that affect the mechanical properties of biocomposites in order to suggest some possible research outlooks that could contribute to optimizing the control of these mechanical properties and expanding the use of biocomposites in industry. [ABSTRACT FROM AUTHOR]

The dissolution behavior of calcium aluminosilicate based glass fibers, such as stone wool fibers, is an important consideration in mineral wool applications for both the longevity of the mineral wool products in humid environments and limiting the health impacts of released and inhaled fibers from the mineral wool product. Balancing these factors requires a molecular-level understanding of calcium aluminosilicate glass dissolution mechanisms, details that are challenging to resolve with experiment alone. Molecular dynamics simulations are a powerful tool capable of providing complementary atomistic insights regarding dissolution; however, they require force fields capable of describing not-only the calcium aluminosilicate surface structure but also the interactions relevant to dissolution phenomena. Here, a new force field capable of describing amorphous calcium aluminosilicate surfaces interfaced with liquid water is developed by fitting parameters to experimental and first principles simulation data of the relevant oxide-water interfaces, including ab initio molecular dynamics simulations performed for this work for the wüstite and periclase interfaces. Simulations of a calcium aluminosilicate surface interfaced with liquid water were used to test this new force field, suggesting moderate ingress of water into the porous glass interface. This design of the force field opens a new avenue for the further study of calcium and network-modifier dissolution phenomena in calcium aluminosilicate glasses and stone wool fibers at liquid water interfaces. [ABSTRACT FROM AUTHOR]

Mixed valence manganites are potential functional materials due to their unique electromagnetic properties. In this work, half-doped ceramics with the perovskite structure Sm 0.5 Ca 0.5 MnO 3 polycrystalline samples are synthesized by the solid-state reaction method in open air at different final sintering temperatures. Structures and particle sizes are studied by x-ray diffraction and scanning electron microscopy, respectively. Positron annihilation spectroscopy and density-functional theory calculations are used to characterize the intrinsic vacancies in the bulk. Thereafter, the effect of vacancies on the magnetic and magnetoresistance (MR) properties is investigated. We find that Mn monovacancies (V Mn ) exist in the bulk among all the samples, and the concentration of V Mn is different. We suggest a possible defect model that can be well applied to explain the phenomena of their electromagnetic properties. The transition temperature of the charge-order state (T CO ) and ferromagnetic and anti-ferromagnetic (T N ) are most likely related to the concentration of V Mn and the particle sizes or pore sizes, respectively. The glass spin state transition temperature seems to be independent of the defect concentration and type. The metal conductive behavior does not appear in a high magnetic field and at low temperatures, which may be caused by the presence of a high concentration of V Mn in the bulk and oxygen-related defects in the boundary, and the double exchange interaction is suppressed. At temperatures below T N and under a weak magnetic field, the MR is related to the total defect concentration. In addition, the high concentration of V Mn is unfavorable for obtaining a high MR value. [ABSTRACT FROM AUTHOR]

This study investigates the residual tensile behaviour of hybrid Carbon Glass fibers reinforced thermoplastic PEEK laminates after they were exposed for 5 min to a hydrogen/oxygen flame. This flame results in a severe thermal aggression characterized by a wall temperature ranging from 900 to 1270 °C and with different heat fluxes (from 200 to 800 kW/m2). The thermally-induced damages were examined by means of microscopic observations and micro CT analyses. The results show that the mass loss linearly depends on the measured heat flux for a 5 min exposure. Depending on the fire testing conditions, the mechanical properties in tension (stiffness and strength) are totally degraded after exposure to the highest heat fluxes (600 and 800 kW/m2) but the retention of the tensile properties is moderate (about −35 to −60% decrease in strength and stiffness, respectively) after exposure to a 200 kW/m2 heat flux. The residual tensile properties of CG/PEEK laminates follow master curves representing the correlations between the mass loss and the changes in the tensile properties regardless the heat flux. These master curves provide a relevant design rule for composite parts to be used under critical service conditions (H 2 /O 2 flame exposure). • The influence of a H 2 /O 2 flame on the behaviour of composite materials was studied. • Wall temperature ranges from 900 to 1270 °C for heat fluxes from 200 to 800 kW/m2. • The mechanical properties are totally degraded after exposure to 600–800 kW/m2. • The changes in the tensile properties are correlated to the mass loss. • Master curves provide a criterion to design composite parts under H 2 /O 2 flame. [ABSTRACT FROM AUTHOR]

In this semi‐quantitative study, laser crystal microparticles which are potentially capable of generating mid‐infrared (MIR) light are incorporated into MIR transmitting optical fibers using a volumetric interface doping technique that combines interface doping with volumetric doping. Using confocal microscopy with a refractive index matching fluid, the Er:YAP microcrystals (MCs) inside the tellurite glass fiber are observed based on the detection of the green upconversion fluorescence emission of Er3+ ions, produced under excitation at 976 nm and localized at the central region within the fiber. The key outcome from this proof‐of‐concept study is that MC particles that are fused with the glass during the fiber drawing process survived heat treatment because the MC particles are exposed for a short time to a glass fluid with high viscosity of ≈105 Pa.s, which prevented the glass from exerting a dissolution effect. The survival of the MCs demonstrated the viability of the doping technique for fabricating fibers with exotic crystal‐glass combinations for applications including good refractive index matching across the pump and lasing bands of rare earth ions. This latter parameter provides significant particle size flexibility whilst minimizing additional loss from scattering especially at MIR wavelengths where the MC diameter‐to‐wavelength ratio becomes smaller. [ABSTRACT FROM AUTHOR]

Metallic glass fibers have high strength, poor plasticity and low Young's modulus. In this study, it was used as a reinforcement to prepare metallic glass fiber reinforced epoxy composites with different fiber volume contents (20%, 30%, 40%, and 50%). The effect of fiber volume contents on the tensile properties of the metallic glass fiber reinforced epoxy composites was studied by experiment and the finite element analysis method. The experiment and simulation results are in good agreement. The tensile strength and plasticity of the metallic glass fiber reinforced epoxy composites increase with the increase of fiber volume contents. When the fiber volume content is 40% or 50%, a sharply necking feature appeared on the fibers and exhibited improved plasticity, due to the formation of interacting and arresting events of shear bands occurring at the interface between the metallic glass fibers and the epoxy. In addition, the strain hardening due to plastic deformation of the metallic glass fibers further enhanced the tensile strength of the metallic glass fiber reinforced epoxy composites. This is a first step toward toughening the inherently brittle metallic glass fibers under tensile conditions. Highlights: A novel CoFeSiB metallic glass fiber reinforced epoxy resin compositeThe increase of fiber volume fraction improves the tensile strength and plasticity of fiber reinforced composites.The strain hardening due to plastic deformation of the metallic glass fibers further enhanced the tensile strength of the metallic glass fiber reinforced epoxy composites. [ABSTRACT FROM AUTHOR]

In this study, we investigate the relationship between structure and properties of fiber–matrix adhesion for material extrusion–based 3‐dimensional (3D) printed composites. We examine the influence of fiber length and fiber content on the tensile properties of glass, basalt, and carbon fiber–reinforced polylactic acid (PLA) composites. Short fiber–reinforced filaments were produced, then, simple micromechanical models were used to predict the in‐plane tensile properties. We found that interlayer tensile properties are strongly influenced by fiber–matrix adhesion. If adhesion is sufficient, the fibers and matrix deform together under tensile load. A second‐order relationship describes interlayer tensile strength in relation to fiber content between 5 and 25 w%, with a maximum at 15 w%, for carbon and basalt fiber–reinforced composites. If adhesion is weak, the crack propagates along the fiber–matrix interface, causing brittle fracture and low strength. This behavior was noted for the glass fiber composite, for which the calculated interface shear strength was the lowest (1.4 MPa). In this case, fiber content is inversely proportional to interlayer tensile strength. Our results show the role of fiber–matrix adhesion quality on tensile properties, which has a major impact on both the accuracy of predictions and the damage processes. Highlights: Critical fiber length determines accuracy of tensile property estimatesQuality of fiber–matrix adhesion governs interlayer damage processPoor adhesion causes brittle fracture and low strengthSecond‐order relationship of interlayer tensile strength and fiber contentLoss of interlayer tensile strength in composite due to fiber–matrix interface [ABSTRACT FROM AUTHOR]

Highlights Recently, thermosetting epoxy resin is expected to be substituted by thermoplastic featured from green circular economy. Poly(methyl methacrylate) (PMMA) has been well known as one promising thermoplastic resin, although its mechanical property needs to be further investigated. In this paper, the free radical polymerization of methyl methacrylate (MMA) was initiated by lauroyl peroxide/N,N‐dimethylaniline (LPO/DMA) and lauroyl peroxide/N,N‐dimethyl‐p‐toluidine (LPO/DMT) redox system at room temperature, respectively. The PMMA (n(MMA:LPO:DMA) = 200:1.2:1) exhibited excellent mechanical properties, and the tensile strength was 66.5 MPa, the bending strength was 118.0 MPa. The tensile strength increased to 78.9 MPa at −40°C, which suggested a promising application at low temperature. The resin was applied to fabricate continuous glass fiber reinforced PMMA (GF/PMMA) composites by vacuum‐assisted resin infusion. The 0° tensile strength and modulus were 1.17 and 43.7 GPa and 90° tensile strength and modulus were 48.3 MPa and 13.2 GPa, respectively. The mechanical properties of GF/PMMA composites are higher than GF/epoxy. Moreover, PMMA resin and glass fiber can be recycled from GF/PMMA composites by MMA as solvent, which is more energy‐efficient and environment‐friendly. This work is of great significance for preparing sustainable resin and composites. GF/PMMA composites were fabricated by vacuum perfusion. GF/PMMA composites showed higher mechanical properties than GF/epoxy. GF/PMMA composite was recycled with MMA and closed‐loop recovery was achieved. [ABSTRACT FROM AUTHOR]

Highlights Two‐phase hybrid modification has been used as an advanced method to improve the strength and toughness of composite. An interfacial modification strategy for simultaneous strengthening, toughening, and damage monitoring of glass fiber (GF)/epoxy composite is proposed by coating rigid multi‐walled carbon nanotubes (MWCNT) and flexible thermoplastic polyurethane (TPU) on the glass fiber surface. The fiber pull‐out and out‐of‐plane experiments were performed to investigate the interfacial modification effect of rigid/flexible hybrid modifier. The results show that the hybrid modifier with a MWCNT/TPU mass ratio of 3:1 (MT@GF‐3/epoxy composite) realizes the most significant enhancement. Specifically, in comparison to GF/epoxy composites, MT@GF‐3/epoxy composite has an increment of 36.52%, 60.96%, 29.56%, and 80.36% in interfacial shear strength (IFSS), transverse fiber bundle test (TFBT) strength, interlaminar shear strength (ILSS) and interlaminar fracture toughness (GIC), respectively, and a significant enhancement in impact resistance. The enhanced interfacial strength and toughness are attributed to the mechanical interlocking, deflection of cracks, and plastic stretching generated by MWCNT and TPU. Results show that the two modifiers interact in a mutually reinforcing way with regard to the strengthening/toughening effects. In addition, multiple mechanical tests confirm the MT@GF/epoxy composites have an excellent damage monitoring ability by recording the resistance change based on the MWCNT's conductive characteristics. This strategy for interfacial modification coating a rigid‐flexible MWCNT/TPU hybrid modifier would offer valuable guidance for improving the strength and toughness of glass fiber/epoxy composites, as well as monitoring and locating the damage. A rigid/flexible hybrid modifier is proposed for modifying the GF/EP composites. The modifier achieves the greatest enhancement at a 3:1 mass ratio of MWCNT/TPU. The mutual reinforcing mechanism between the rigid/flexible phases is analyzed. Damage monitoring is realized for the modified GF/EP composites. [ABSTRACT FROM AUTHOR]

Highlights A detailed investigation was employed on the manufacturing process of Glass Fiber (GF) reinforced poly‐L‐lactide (PLLA) composites (GFRP) during in‐situ PLLA polymerization using Resin Transfer Molding (RTM). The lower viscosity of lactide, in comparison to PLLA, led to a strong interaction between PLLA and GF as a result of improved penetration into the fiber matrix, resulting in a high conversion rate of 100% for GFRP and 91.9% for PLLA. GF incorporation into the composite material resulted in an improved crystallinity of 55.65% for GFRP, where PLLA showed crystallinity of 36.5%. A GFRP composite with exceptional mechanical properties, including 122.3 MPa tensile strength and 4.485 GPa modulus, was achieved. Both surface and bulk erosion were seen during the breakdown of these composites. These composites seem to be a viable substitute for metallic implants in biological applications. In situ, resin transfer molding of poly‐l‐lactide and GF composite. Higher volume fraction such as 40% w/v loading of GF into composites. 1% conversion of GFRP is achieved. GFRP shows the machinal strength of 122 MPa and harness of 4.2 GPa. Biocompatibility of GFRP composites in body stimulated conditions. [ABSTRACT FROM AUTHOR]

Bismuth (Bi) and Germanium (Ge) co‐doped silica glass and fiber, as advanced gain media with broadband near‐infrared (NIR) emission and amplification, have promise for extending communication bandwidth. However, efficiently modulating the NIR emissions of bismuth to cover the C+L communication bands remain a significant challenge. In the study, a high‐temperature and high‐pressure reduction treatment on Bi/Ge co‐doped silica glass is employed to tailor the coordination environment around bismuth active center. This method facilitated the creation of new bismuth NIR luminescence centers, resulting in the luminescence spectrum with a peak position at 1550 nm and a FWHM exceeding 350 nm. The changes in the bismuth coordination environment are elucidated using HRTEM, photoluminescence decay, temperature‐dependent emission, EXAFS and CW‐EPR. Furthermore, the feasibility of this method in Bi/Ge co‐doped silica fiber is validated, and obtained >5 dB amplification in the range of 1400–1700 nm. This coordination engineering method holds significant potential for widespread application in Bi/Ge co‐doped silica glass and optical fiber is believed. It presents a promising prospect for expanding communication bandwidth by effectively modulating the NIR emissions of bismuth to cover the S to U communication band. [ABSTRACT FROM AUTHOR]

Titanium dioxide-enriched phosphate glasses are esteemed for their applicability in the biomaterial area, yet the investigation into the influence of TiO 2 on the crystallization dynamics of glass melts and the spinnability of sodium-calcium-magnesium phosphate glasses remains unclear. To elucidate these effects, sodium-calcium-magnesium phosphate glasses with 0, 5, and 10 mol% of TiO 2 have been prepared using the melt-quenching method, and glass fibers were drawn from the correspondent glass melts. FTIR and Raman spectroscopy have disclosed that the introduction of TiO 2 induces a depolymerization in phosphate network, causing a transition from Q2 species to Q1 units, and reduction in both the theoretical network connectivity (NC theor) and the average chain length (n theor). Meanwhile, the interposition of TiO 2 also gives rise to the replacement of P–O–P linkages with P–O–Ti bonds, along with the formation of [TiO 5 ] groups. This structural transformation resulted in the increase in molar volume and the coefficient of thermal expansion (CTE), concurrently lowering the glass transition and softening points. Evidently, the TiO 2 -free glass exhibited crystallization across a temperature range spanning from its transition to the liquidus temperature. However, the introduction of TiO 2 and the subsequent formation of P–O–Ti bonds effectively inhibited crystallization, which is favorable for drawing glass fibers. Analyses of viscosity-temperature relationships using various rheological models suggested that TiO 2 raises fragility for all glasses, suggesting a more "open" structure in the glass melts, which can be supported by the increment in free volume. The m-D diagram failed to describe the enhancement in spinnability imparted from TiO 2. While, the quantitative fiber spinnability index (K fib) increases with higher TiO 2 content, as a successful indicative of an improved ability to form fibers. [ABSTRACT FROM AUTHOR]

Glass-based sealing materials exhibit significant potential for utilization in solid oxide fuel cells (SOFCs). We conducted a study on the impact of mullite fibers with varying particle sizes on glass composite sealing materials. We evaluated and discussed properties such as coefficient of thermal expansion (CTE), softening temperature (Ts), gastightness, interfacial compatibility, and flexural strength of the sealing materials with different ranges of fiber particle sizes. Our findings indicate that the three different particle sizes of mullite fiber-glass composite sealing materials met the required coefficients of thermal expansion, displayed good interfacial compatibility, and exhibited gastightness lower than 0.0016 sccm cm−1. Notably, the mullite fiber-reinforced sealing material that underwent ball-milling for 1 h outperformed the other two variants. It demonstrated fewer defects, a 57.1 % increase in flexural strength, and a 117.4 % higher maximum strain value. [ABSTRACT FROM AUTHOR]

Highlights In this study, the axial crushing response and energy‐absorbing mechanisms of circular composite tubes, which were reinforced by carbon fiber (C10) and carbon/glass hybrids (C3G4C3), were investigated experimentally and numerically. Both samples exhibited similar crushing responses comprising delamination and intralayer shear failure. The impact kinetic energy is primarily converted into frictional and composite damage energies. C3G4C3 had poorer crashworthiness with a mean crushing force and specific energy absorption of 313.3 kN and 58.0 kJ/kg, which are by 39.3% and 30.8% less, respectively, than those of C10. The influence of glass fiber reinforced polymers (GFRP) content (hybrid ratio) and stacking sequence on tubal crashworthiness was investigated numerically. For composite tubes with a hybrid ratio of 40%, the central distribution of GFRP (C3G4C3) achieved optimal energy absorption performance. Additionally, when GFRP layers were centralized stacked, a reduction of the hybrid ratio from 60% (G3C4G3) to 20% (GC8G) helped improve the crashworthiness of the hybrid tubes, where the mean crushing force increased by 23%. Impact responses of composite tubes reinforced by carbon fiber and carbon/glass hybrids were investigated experimentally and numerically. Carbon/glass hybrid tubes exhibited lower crashworthiness. The effects of stacking sequence and hybrid ratio on the energy absorption performance were studied. [ABSTRACT FROM AUTHOR]

Highlights Present study comprehensively explores the phenomenon of in‐plane fiber waviness in glass/epoxy fiber reinforced polymer (GFRP) composites. Utilizing a pioneering technique that employs a semi‐circular bar to induce controlled fiber waviness, coupled with image processing using OpenCV library in Python coding for precise measurement and analysis of in‐plane fiber waviness. This defect is commonly found in components fabricated with fiber‐reinforced composites. During the process of manufacturing fibers may deviate from their intended orientation due to process variables or resin flow dynamics. Understanding in‐plane fiber waviness is crucial due to its impact on mechanical properties of composites. It is essential for optimizing manufacturing processes and ensuring enhanced structural performance in diverse engineering applications through analysis of strength and failure mechanism. A novel study was conducted by introducing a circular cutout within the fiber waviness region to investigate the combined effect of multiple defects. The experimental tensile test reveals that as waviness ratio (WR) increases a significant decrease in its tensile strength and vice versa. The study incorporates scanning electron microscopy (SEM) image analysis to examine composite failure. By advancing the understanding of in‐plane fiber waviness and its implications, this research significantly contributes to ongoing efforts in composite design and optimization. Adopting a cutting‐edge method to create controlled fiber waviness that makes use of a semi‐circular bar. Image processing with Python code that makes use of the OpenCV package to precisely measure and analyze in‐plane fiber waviness. A new investigation was carried out to examine the combined effect of multiple flaws by creating a circular cutout within the fiber waviness zone. [ABSTRACT FROM AUTHOR]

In this study, the post‐buckling damage behavior of cylindrical composite tubes was examined experimentally. The samples were reinforced with glass, carbon, and kevlar fibers to obtain glass‐reinforced fiber polymer (GRFP), carbon‐reinforced fiber polymer (CRFP), and Kevlar‐reinforced fiber polymer (KRFP) cylindrical tubes. The samples were produced using 4 stacking layers with filament winding technology. In producing all composite tubes, the outer diameter was kept constant at 17 mm, and two inner diameters of 12 and 13 mm, two wall thicknesses, 5 winding angles, and two lengths were used as parameters. The load was applied to the samples until completely damaged, and the maximum post‐buckling load values obtained were measured on the testing device. The effect of different reinforcement materials, winding angle, wall thickness, and length on the load‐carrying capacity was analyzed and it was understood that they had a significant effect. It was observed that the load‐carrying capacity of GFRP samples was the highest compared to the others, followed by CFRP and KFRP samples, respectively. In all samples, it was observed that a 0.5 mm wall thickness increase increased the load‐carrying capacity, while a 50 mm length increase decreased it. The energy absorption (EA) values of GFRP, CFRP, and KFRP samples were 46.99, 25.22, and 15.48 Joules, respectively. It was understood that the energy absorption of GFRP samples was 1.86 times better than CFRP and 3 times better than KFRP. Highlights: The samples were produced using the fiber winding method, which is one of the most common production methods in the manufacture of tubes.Three different polymer reinforcement materials were used in the production of the samples.The effects of polymer reinforcement material, winding angle, length, and wall thickness on the maximum post‐buckling load were investigated.Wall thickness was found to have a significant effect on the maximum post‐buckling load.It was observed that GFRP samples had the highest energy absorption feature. [ABSTRACT FROM AUTHOR]

This research aimed to understand how the incorporation of nanocarbon powder (NCP) influences the crashworthiness performance of glass fiber‐reinforced epoxy (GFRE) tubular components, potentially offering insights into improving the safety and resilience of structures or vehicles. Consequently, the crashworthiness behaviors of circular tubes made of GFRE with varying amounts of NCP was studied. Utilizing wet‐wrapping through hand lay‐up technique, GFRE tubes were fabricated with various weight percentages of NCP, that is, 0, 0.25, 0.50, 1, 2, 3, and 4 wt.%. Following that, the crashing load, total absorbed energy against displacement responses, and deformation histories of these tubes under quasi‐static axial loading conditions were calculated and tracked. As part of the crashworthiness analysis, critical indicators were evaluated, including initial peak load (Fip), total absorbed energy (U), mean crash force (Fm), crash force efficiency (CFE), and specific energy absorption (SEA). The findings reveal that the maximum Fip, U, Fm, and SEA were noted at 0.5 wt.% of NCP, with increasing percent's of 30.80, 12.17, 12.16, and 7.50, respectively, compared to the unfilled tube. While, the CFE was recorded by 3 wt.% of NCP with an enhancement of 16.67%. It is worth to note that, the findings reveal that the inclusion of NCP increases crashworthiness metrics up, that is, Fip, U, Fm, and SEA to a concentration of 0.50 wt.% NCP. However, beyond this point, there's a notable decline in performance. Highlights: The GFRE tubes were filled with various wt.% of NCP.The planned tubes were made using hand lay‐up methods.The tubes were subjected to axial compression loads to examine their crashing behavior.The crashing load and absorbed energy versus displacement responses for tubes were exposed.The experimental results were analyzed and discussed. [ABSTRACT FROM AUTHOR]

This study introduces an innovative approach to enhance the absorption capabilities of skin‐core dual‐domain structure radar‐absorbing materials (SDSRAM) composed of thin‐ply laminates and honeycomb. The upper skin laminates consist of transmissive skin and impedance matching layer. The impedance matching layer was hot‐pressed using functionalized absorbed thin‐ply glass fibers prepregs, flaked carbonyl iron powder (FCIP) and multi‐walled carbon nanotubes (MWCNTs) as the absorber. The lower skin was manufactured using carbon fiber‐plated nickel. The core is prepared by honeycomb modified (HCM). The permittivity and permeability of the skin laminates and the HCM were measured by wave‐guide method. The impact of FCIP/MWCNT on the electromagnetic (EM) parameters of the thin‐ply laminates and the influence of MWCNTs on the permittivity of the honeycomb were investigated. Microwave absorption properties of SDSRAM were assessed through the measurement of reflection loss (RL) using the arch method and simulated using the microwave simulation software CST studio suite 2020. Experimental verification was conducted to confirm the absorbing performance. The results show that the effective absorption bandwidth (RL < 10 dB) of SDSRAM covers the frequency range of 2.2–18 GHz, with a maximum absorption intensity of −42.5 dB. The introduction of the thin‐ply laminates caused a shift in the peak of the reflectance curve toward lower frequencies. Highlights: Functionalized absorbed glass fibers were prepared using fiber spreading functional sizing integrated process.A new skin‐core dual‐domain synergistic modulation absorbed structure was developed with thin‐ply laminates and modified honeycomb. Its broadband absorption mechanism was discussed.Desired broadband absorption performance was acquired with thin thickness. [ABSTRACT FROM AUTHOR]

Biological structures achieve remarkable material performance owing to naturally assembled structures that extend from the molecular to macro‐scale. Synergy among constituents of various length scales yields lightweight, hierarchically structured materials with properties superior to those of individual components. To replicate nature's ingenuity, this work emulates the cylindrical core‐shell structure found in osteons and bamboo, utilizing Halloysite Nanotubes (HNTs) and Glass Fibers (GFs) in a semi‐crystalline polymer matrix. HNTs are environmentally friendly, naturally occurring tubular aluminosilicates with high aspect ratios, large lumen volumes, and low cost, and are readily dispersible in polymer matrices. Here, hierarchical reinforcement is achieved through controlled electrostatic assembly of HNTs onto GFs and subsequent trans‐crystallization‐encapsulation. This cylindrical core‐shell architecture yields composites with exceptional mechanical performance, superior thermal management (insulation/stability), improved industrial processability, and reduced flame propagation speed. Compared to the current industrial composite substitute for metallic structural components, the hybrid composites exhibit a remarkable 84% increase in impact strength, 27% increase in specific tensile strength, 56% increase in tensile toughness, and 30% in specific flexural strength, accompanied by a 20% weight reduction and a 255% increase in processability (melt‐flow index). This scalable assembly strategy marks a cornerstone in lightweight multifunctional materials development, to conquer future sustainability targets. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Material and Methods Results Conclusion To evaluate the plant‐derived compound lignin (LIG) as a pretreatment of intraradicular dentin in combination with EDTA on push‐out bond strength (PBS) and nanoleakage of the glass fiber posts (GFPs) cemented using adhesive resin cement.Twenty‐eight human incisor roots were prepared for GFP cementation and divided based on dentin pretreatment: (1) CONTROL: no pretreatment, (2) EDTA: 17% EDTA for 3 min, (3) EDTA‐LIG: 17% EDTA and 2% lignin for 3 min, (4) EDTA‐PAC: 17% EDTA and 2% lignin for 3 min. The GFPs were cemented using the self‐adhesive resin cement Multilink Speed. The roots (n = 7) were sectioned into 1 mm‐thick discs and subjected to PBS testing after 1 week or 6 months. Nanoleakage was analyzed by SEM. Statistical analysis was performed using two‐factor ANOVA and Tukey's test (p < 0.05).Higher PBS was identified for the CONTROL group (p < 0.001). After 6 months, the EDTA‐LIG maintained the bond strength with a predominance of mixed failures, while the EDTA‐PAC, EDTA, and CONTROL groups showed reduction of bond strength, with a predominance of adhesive failures along with severe silver infiltration in the interface.LIG associated with EDTA as a pretreatment for intraradicular dentin shows significant potential for attaining stable bond strength and interfacial integrity of self‐adhesive resin cement to intraradicular dentin. [ABSTRACT FROM AUTHOR]

In this study, high loadings of boron nitride (BN) nanoplatelets were added to silica fiber-reinforced phenolic composites to study the multifunctional impact of BN loading and manufacturing processing on the subsequent mechanical, thermal, and thermomechanical properties. A series of high-quality laminates were made with various loadings of BN using compression-molded out-of-autoclave processing. Three-point bend and short beam shear testing determined the relationship between BN loading and mechanical performance. The fracture properties were analyzed using optical and scanning electron microscopy. The thermal conductivity performance was increased up to a 93% improvement, indicating the thermal management multifunctionality of the modified composites without changing the crosslinking ability or glass transition temperature significantly. The modified performance of hybrid silica/phenolic/BN composites is demonstrated through micromechanical multiscale modeling, where BN loading and particle stress concentrations impact the modulus and strength of the composite. [ABSTRACT FROM AUTHOR]

This paper proposes a multi-objective optimization method for injection molding, combining the random forest (RF) model optimized using the light spectrum optimizer (LSO) with the non-dominated sorting whale optimization algorithm (NSWOA), to tackle the quality defects of warpage deformation and volume shrinkage commonly observed for the glass fiber injection molded product. Based on the simulation results of central composite face centered design (CCF), the model for control of injection molding quality defects using LSO-RF is constructed. NSWOA is used for multi-objective optimization to obtain the Pareto solutions, and the critic method is employed to determine the optimal process parameter scheme. Then, the optimal process parameter scheme is inputted to Moldflow for simulation verification. The validation results demonstrate that the LSO-RF model achieves prediction errors within 3 % for warpage deformation and volume shrinkage, indicating good predictive accuracy. The optimized warpage deformation and volume shrinkage are 0.3519 mm and 7.0930 %, respectively. Compared to the pre-optimized state, the warpage deformation decreased by 32.57 % and the volume shrinkage decreased by 15.93 %, indicating a significant improvement in molding quality for the glass fiber injection molded product. [ABSTRACT FROM AUTHOR]

Short-fiber reinforcement is a potent approach to improving the material properties of injection-molded parts. The main consideration in such reinforced materials is to preserve the fiber length, as this is the major influence on the properties of a given composite. The aim of this work was to investigate the different influencing parameters in injection molding processing on the properties of short carbon and glass fiber-reinforced polypropylene. We investigated parameters like melt temperature and back pressure, but also machine size and pre-heating regarding their influence on the tensile properties. We found that adjustments of melt temperature and back pressure only yield small improvements in the fiber length and the tensile properties, also depending on machine size, but a pre-heating step of the granules can significantly improve the properties. [ABSTRACT FROM AUTHOR]

Thermoplastic fiberglass was compression molded in the form of thick panels with a nominal thickness of 10 mm and a size of 300 × 300 mm2. A simplified procedure was adopted to speed up the lamination procedure and adapt it to the aim of recycling waste, glass fibers, fabrics, and thermoplastic films. Low density polyethylene was used as a matrix to simplify the laboratory process, but the same procedure can be extended to other thermoplastic film, such as polyamide. The final thermoplastic composite shows unique properties in terms of its repairability, and its performance was improved by increasing the number of repairing repetitions. For this aim, a repairability test was designed in the bending configuration, and three consecutive cycles of bending/repairing/bending were carried out. The static mechanical properties of the final thermoplastic composite were, conversely, low in comparison with traditional fiberglass because of the choice of a polyethylene matrix. The bending tests showed that the maximum strength was lower than 10 MPa and the elastic modulus was less than 1 GPa. Nevertheless, the toughness of the thermoplastic composite was high, and the samples continued to deform under bending without splitting into two halves. [ABSTRACT FROM AUTHOR]

This study investigates the repair of damaged curved glass/epoxy composite laminates through various adhesive reinforcements and adhesively bonded external patches. The experimental procedures involve fabricating laminates, conducting four-point bending tests, quasi-static indentation tests, and optimizing damaged areas. Results demonstrate the influence of repairs on curved beam strength and interlaminar tensile strength. Adhesive repairs with chopped fiber reinforcement outperform plain epoxy and particle fiber-reinforced repairs, preserving 51.28% of curved beam strength. Adhesively bonded external patches, both single and double, with chopped fiber reinforcement exhibit significant strength recovery 72.08% and 80.78% compared to virgin samples. The study emphasizes the effectiveness of adhesively bonded external patches, particularly those with chopped glass fiber reinforcement, in enhancing curved beam strength and interlaminar tensile strength. This research provides valuable insights for repairing angled structures, such as those in airplane components, showcasing potential applications of these techniques for structural maintenance. HIGHLIGHTS: Investigated adhesive reinforcements and bonded external patches for curved composites. Laminates fabricated, tested for bending, indentation, and optimized in damaged region Chopped fiber adhesive repairs preserve significant 51.28% strength. Adhesively bonded patches exhibit 72.08% and 80.78% strength recovery. [ABSTRACT FROM AUTHOR]

In the automotive industry, short glass fiber-reinforced thermoplastics are widely used under the hood and subjected to dynamic vibrations of the engine in multiple directions resulting in fatigue failure. Under fatigue loading, a significant portion of the strain energy is stored within the material, while the remaining portion is lost due to internal frictions and the damage occurrence. Internal friction results in heat generation, which in turn causes an increase in external temperature. This increase in temperature leads to thermal degradation of the polymer. Investigations on the cause of the stiffness drop are not widely available in the literature. Therefore, this study explores the source of the stiffness drop under biaxial fatigue loading of a polyamide 6,6 reinforced with 30 wt. % short glass fibers (PA66GF30) and distinguishes the contributions of thermal degradation and damage accumulation. The thermal evolution of the specimens was captured by means of thermography. In addition, the digital image correlation (DIC) technique was used to measure the in situ strain field during the fatigue. Despite the temperature stabilization being observed around the 10,000th cycle, the reduction in the stiffness continued until failure which was attributed to the mechanical damage accumulation and cyclic creep during the fatigue tests. Dynamic mechanical analyses (DMA) were carried out to quantify the stiffness drop with the varying temperature. From the results, it is seen that the damage accumulation and cyclic creep during the fatigue tests were responsible for the major part of the stiffness drop. Finally, scanning electron microscopy (SEM) inspection of the fracture surface was performed to identify fatigue damage mechanisms. Four unique features associated with the fatigue damage were identified: (1) debonding of fibers from the matrix, (2) polymer matrix crazing, and (3) cavitation and porosities, (4) pull out fiber ends and break on the fiber. [ABSTRACT FROM AUTHOR]

Users of the microbond test assume that a microbond resin droplet's properties are equivalent to a macroscale specimen. However, there is currently no standardised methodology for determining the cure state of droplet specimens used in the microbond test. In this paper, we present a technique for microbond test users to better understand the properties of thermoset droplet specimens. Utilising a conventional benchtop spectrometer, a novel sample preparation technique involving curing epoxy droplets on thin-steel filaments allowed for high-throughput determination of the microbond droplet cure state. The parity between steel filament and glass fibre microbond samples was confirmed by infrared microspectroscopy. It is shown that cure schedules used in manufacturing composite parts produced microbond droplets with degrees of cure lower than that of bulk matrix specimens subjected to an identical thermal history. Testable microbond droplets could only be prepared for commercial resin systems when introducing a room temperature pre-curing time of at least 2 h. It is concluded that microbond testing should be supported by some droplet cure state characterisation methods to ensure that interfacial effects are not artefacts of droplet sample preparation. [ABSTRACT FROM AUTHOR]

To evaluate the effect of different ratios of Bis-EMA/Bis-GMA resin mixtures on the inherent viscosity and curing-related properties: including degree of cure (DC%), shrinkage strain, Knoop micro-hardness (KH) and flexural strength of resin-impregnated fiber-bundles. Bis-EMA/Bis-GMA monomers were mixed (by weight) in the following ratios: M1 = 30 %/70 %, M2 = 50 %/50 %, M3 = 70 %/30 %, and M4 = 100 %/0 %. Standard measurements were made of refractive index, viscosity, degree of conversion, shrinkage strain and Knoop hardness (KHN). For 60 % glass fiber-bundles impregnated with 40 % resin, three-point bending test for flexural strength and shrinkage strain were measured. Data were analyzed by One-way ANOVA and Bonferroni post-hoc tests (α = 0.05). For resin mixtures, increasing Bis-EMA proportion decreased refractive index (p < 0.05), and viscosity (p < 0.05), and increased monomer conversion (DC%), shrinkage strain and KHN (p < 0.05). DC% increased after 1 h for all resin mixtures. The shrinkage strain and flexural strength of resin-impregnated fiber-bundles reduced with increased Bis-EMA. Monomeric mixtures with highest amounts of Bis-EMA showed enhancement in several clinically-relevant properties and polymerization of respective resin-impregnated glass fibers. This makes them potential candidates for impregnating glass fibers in fiber-reinforced restorations. [ABSTRACT FROM AUTHOR]

Geopolymer lightweight cellular concrete (GLCC) combines the advantages of geopolymer and LCC but also suffers from the inherent deficiency of low strength, which can be improved by introducing suitable reinforcing materials such as fibers. This paper investigated the mechanical properties and microstructure of fly ash-slag-based GLCC reinforced with glass fibers (GLCCRGF), aiming to reveal the strengthening mechanism of glass fibers. The effects of different fiber contents (0.0, 0.3, 0.6, 0.9, and 1.2%), fiber lengths (3, 6, 9, 12, and 15 mm), and fiber-blending methods (G-R, G-W, and G-S) on the mechanical properties of GLCCRGF were analyzed. The results showed that the fiber incorporation had no significant or even negative effect on the compressive strength but significantly improved the splitting tensile strength. The optimal results of fiber content, fiber length, and fiber-blending method are 0.6%, 9 mm, and G-R, respectively. From the microstructure perspective, optical tests were conducted to explore the evolution rules of pore size, pore shape factor, and fractal dimension of pore distribution of GLCCRGF. The results showed that the incorporation of glass fibers (0.6%, 9 mm, and G-R) improved the pore characteristics and contributed to more uniform pore distribution. Furthermore, scanning electron microscopy (SEM) was employed to observe the micromorphology of the skeleton structure of GLCCRGF. The SEM results showed excellent interfacial bonding between glass fibers and the geopolymer matrix. Due to good bonding quality and crack-bridging effect, the presence of glass fibers enhanced the strength and crack resistance of the matrix. [ABSTRACT FROM AUTHOR]

To effectively manage turbine blade weight and blade deflection under severe weather conditions, longer and stiffer blades are required, fiber glass producers have devoted significant efforts to developing and commercializing high‐modulus (HM) glass fiber products of the first generation. The current focuses aim at the commercialization of the second generation and the development of the third‐generation products. This article briefly reviews four key areas: (a) the benefit of longer blades on wind energy generation, (b) characteristics of HM glass fibers of various generations, (c) fundamental science and understanding behind HM glass fiber development, and (d) finally statistically based composition (C)–property (P) and structure (S)–property (P) modeling approaches in new glass design. [ABSTRACT FROM AUTHOR]

[Display omitted] • Swelling-assisted pyrolysis was proposed for the recovery of glass fibers from WTBs. • Resin decomposition ratio reached 76.8 % at 350 °C in swelling-assisted pyrolysis. • The swelling treatment physically disrupted the cross-linked structure of the WTBs. • The oxidation duration was reduced owing to the less content of pyrolysis char. • Tensile strength of fibers from swollen-WTB was higher than that from original-WTB. The recycling of end-of-life wind turbine blades has become a global environmental challenge driven by the rapid growth of wind power. Pyrolysis is a promising method for recovering glass fibers from these discarded blades, but traditional pyrolysis is often operated at high temperatures, which degrades the mechanical properties of recovered fibers. To address this issue, a swelling-assisted pyrolysis method was proposed to recover high-quality glass fibers from end-of-life wind turbine blades at low temperatures. The results confirmed that the decomposition of the resin matrix within the blade was significantly promoted at low temperatures in the swelling-assisted pyrolysis process, achieving a resin decomposition ratio of 76.8 % at 350 °C. This improvement was attributed to enhanced heat transfer and co-pyrolysis with acetic acid. Swelling could physically disrupt the cross-linked structure of the blade, creating a more porous and layered structure, thereby enhancing heat transfer during the pyrolysis process. Simultaneously, the co-pyrolysis with acetic acid could generate hydrogen radicals, which promoted the cracking of macromolecular oligomers into lighter products or gaseous alkanes. Consequently, the formation of pyrolysis char within the solid pyrolysis product was reduced, shortening the oxidation duration to 30 min. In comparison to traditional pyrolysis, the swelling-assisted pyrolysis process effectively suppressed the diffusion of surface defects over the recovered fibers, leading to promising improvements in their flexibility, elasticity, and mechanical properties, with tensile strength notably increased by 27.5 %. These findings provided valuable insights into recovering high-quality glass fibers from end-of-life wind turbine blades. [ABSTRACT FROM AUTHOR]

The paper deals with the influence of the brittleness of glass fibers on the selected performance properties of the fibrous polymer composite. Understanding the fatigue behavior of fiber-reinforced plastics is desirable for exploiting their features in safe, durable, and reliable industrial components. Based on the proposed methodology, it is possible to assess the impact of material reuse on selected mechanical and rheological properties. To verify the methodology by experimental analysis, homopolymer PP reinforced with chemically grafted glass fiber (30 wt%) was selected. The proposed methodology was subsequently verified by experimental analysis and evaluated statistically. The morphology of the fracture surfaces was evaluated, and the fiber-polymer matrix adhesion was monitored at the interface of the fracture surfaces. Based on the measured and evaluated values and fracture surfaces, we can say that the brittleness of the fibers significantly affects the performance properties of the tested polymer composite. [ABSTRACT FROM AUTHOR]

Thermal neutron detection with scintillating fibers has excellent scientific and technological potential for remote and spatially resolved detection. However, most fibers are polymers, and developing all‐inorganic scintillating fibers remains a significant challenge. Herein, all‐inorganic scintillating fibers and prototype neutron detection devices are successfully constructed for neutron detection. The scintillating fibers with a perfect waveguide configuration and tunable size have been fabricated through the melt‐in‐tube method. The interactions between the thermal neutron and scintillating fiber have been theoretically analyzed. The dependence of the neutron absorption ability on the core diameter, cladding thickness, and 6Li abundance has been investigated. Guided by the above experimental and theoretical results, the configuration of the scintillating fiber and the corresponding neutron detection prototype device has been built. Its practical application for neutron detection has been demonstrated, and importantly, the single thermal neutron event can be successfully monitored. The device shows great promise for neutron detection applications in special scenarios such as tiny space and electromagnetic interference environments. [ABSTRACT FROM AUTHOR]

Highlights Despite the low density and high specific strength properties, the fiber‐reinforced composites are characterized by a relatively low interlaminar fracture toughness and their ultimate properties are strongly affected by the fiber matrix adhesion. This study aims to investigate the influence of fiber surface treatments, such as UV and atmospheric plasma, and of the interfacial shear strength, on the flexural properties and Mode I interlaminar fracture toughness of glass fiber epoxy composites. The vacuum‐assisted resin infusion technique is used for the composite fabrication. Scanning Electron Microscopy analysis is used to observe and to explain the changes in the morphology of the fibers after surface treatment. Remarkably, the results showed an overall reduction in the mechanical properties. The interfacial shear strength values of the UV and plasma‐treated samples were reduced by 34.9% and 49.5% respectively. The flexural strength was reduced by 7.9% and 5.9% respectively. The Mode I fracture toughness values for the UV and plasma‐treated samples were also reduced by 49.8% and 62.2% respectively. UV and plasma treatments were performed on glass fibers to improve performance. Push‐out tests were carried out to evaluate fiber/matrix adhesion. An aerospace grade epoxy resin curing in thermal press‐clave was used. Mechanical tests related Interfacial Shear Strength to composites performance. [ABSTRACT FROM AUTHOR]

Highlights In recent years, there has been a significant emphasis on the development of composite materials that are both high‐performing and environmentally friendly. Hybrid polymer composites that are reinforced by both sisal and glass fibers are introduced in this study. Investigation was conducted to evaluate the combined influence of hybrid reinforcements and Egg Shell Powder (ESP) on the mechanical properties of the composites. The hand layup technique was employed to create hybrid laminates by incorporating variable amounts of ESP (0–15 wt%) and employing various stacking sequences. Various mechanical testing was administered to the composites that had been prepared. The results indicated that the glass/sisal hybrid laminates exhibited superior mechanical properties in comparison to the non‐hybrid sisal laminates, which was attributed to the synergistic benefits of incorporating both sisal and glass fibers. The incorporation of Egg Shell Powder significantly improved the material's mechanical properties. The glass/sisal hybrid laminates with 15% ESP laminate demonstrated the maximum tensile strength (195.23 MPa), flexural strength (150.02 MPa), and ILSS (7.55 MPa). Scanning electron microscopy enabled a comprehensive analysis of the hybrid composites' interfacial adhesion and microstructure. This investigation verified that the ESP was effectively dispersed and had a substantial effect on the interface between the matrix and the fibers. The hybrid composites that are generated are environmentally friendly and exhibit extraordinary potential for a variety of applications, offering a sustainable and high‐performing alternative to conventional synthetic composites. These discoveries promote the utilization of bio‐based resources in the composites industry and advance the development of sustainable materials. The glass/sisal hybrid laminates with 15% ESP laminate showed highest tensile strength of 195.23 MPa Hybrid composites exhibited superior mechanical properties. ESP addition significantly improved interfacial adhesion and strength Water absorption decreased with increasing ESP content up to 15% Development of Eco‐friendly composites suitable for automotive and aerospace applications [ABSTRACT FROM AUTHOR]

Highlights Unique hybrid thermoplastic composites based on polyoxymethylene copolymer (POM C), 10 wt.% glass fiber (GF) and graphite (Grt) filler at 1, 3, and 5 wt.% were developed using injection molding technique. According to the Taguchi L16 orthogonal array, present experiments were carried out with the aim of determining the coefficient of friction (COF) and specific wear rate (SWR) under a range of loads (namely, 5, 10, 20, and 30 N), sliding speeds (namely, 200, 400, 600, and 800 rpm), and run times (namely, 15, 30, 45, and 60 min) with varying wt.% of Grt (namely, 1, 3, and 5 wt.%) throughout the experiment. Analysis of variance (ANOVA) was used to evaluate the most significant factors that affect the output functions (viz., COF and SWR). The findings demonstrated that POM C/10GF composites' tribo‐mechanical, structural, and thermal properties were considerably improved upon by including Grt. Various microscopical methods were also employed to study the wear mechanisms of the composites and the surface morphology of the worn samples. The POM C/10GF with a 3 wt.% of Grt exhibited superior tribological properties owing to its enhanced interfacial bonding characteristics, resulting to increased wear resistance. Injection molded POM C/10GF hybrid composites with 1, 3, and 5 wt.% graphite (Grt) Structural, thermal, chemical, tribo‐mechanical and microstructural studies Design of experiment with variable loads, times, speeds, and Grt compositions COF and specific wear resistance as response Optimization of hybrid composite composition using Taguchi L16 orthogonal array [ABSTRACT FROM AUTHOR]

The aim of this study was to optimize a set of technological parameters (travel speed, extruder temperature, and extrusion rate) for 3D printing with a PEEK-based composite reinforced with 30 wt.% glass fibers (GFs). For this purpose, both Taguchi and finite element methods (FEM) were utilized. The artificial neural networks (ANNs) were implemented for computer simulation of full-scale experiments. Computed tomography of the additively manufactured (AM) samples showed that the optimal 3D printing parameters were the extruder temperature of 460 °C, the travel speed of 20 mm/min, and the extrusion rate of 4 rpm (the microextruder screw rotation speed). These values correlated well with those obtained by computer simulation using the ANNs. In such cases, the homogeneous micro- and macro-structures were formed with minimal sample distortions and porosity levels within 10 vol.% of both structures. The most likely reason for porosity was the expansion of the molten polymer when it had been squeezed out from the microextruder nozzle. It was concluded that the mechanical properties of such samples can be improved both by changing the 3D printing strategy to ensure the preferential orientation of GFs along the building direction and by reducing porosity via post-printing treatment or ultrasonic compaction. [ABSTRACT FROM AUTHOR]

Room‐temperature sodium‐sulfur (RT Na−S) batteries, noted for their low material costs and high energy density, are emerging as a promising alternative to lithium‐ion batteries (LIBs) in various applications including power grids and standalone renewable energy systems. These batteries are commonly assembled with glass fiber membranes, which face significant challenges like the dissolution of polysulfides, sluggish sulfur conversion kinetics, and the growth of Na dendrites. Here, we develop an amorphous two‐dimensional (2D) iron tin oxide (A‐FeSnOx) nanosheet with hierarchical vacancies, including abundant oxygen vacancies (Ovs) and nano‐sized perforations, that can be assembled into a multifunctional layer overlaying commercial separators for RT Na−S batteries. The Ovs offer strong adsorption and abundant catalytic sites for polysulfides, while the defect concentration is finely tuned to elucidate the polysulfides conversion mechanisms. The nano‐sized perforations aid in regulating Na ions transport, resulting in uniform Na deposition. Moreover, the strategic addition of trace amounts of Ti3C2 (MXene) forms an amorphous/crystalline (A/C) interface that significantly improves the mechanical properties of the separator and suppresses dendrite growth. As a result, the task‐specific layer achieves ultra‐light (~0.1 mg cm−2), ultra‐thin (~200 nm), and ultra‐robust (modulus=4.9 GPa) characteristics. Consequently, the RT Na−S battery maintained a high capacity of 610.3 mAh g−1 and an average Coulombic efficiency of 99.9 % after 400 cycles at 0.5 C. [ABSTRACT FROM AUTHOR]

Room‐temperature sodium‐sulfur (RT Na−S) batteries, noted for their low material costs and high energy density, are emerging as a promising alternative to lithium‐ion batteries (LIBs) in various applications including power grids and standalone renewable energy systems. These batteries are commonly assembled with glass fiber membranes, which face significant challenges like the dissolution of polysulfides, sluggish sulfur conversion kinetics, and the growth of Na dendrites. Here, we develop an amorphous two‐dimensional (2D) iron tin oxide (A‐FeSnOx) nanosheet with hierarchical vacancies, including abundant oxygen vacancies (Ovs) and nano‐sized perforations, that can be assembled into a multifunctional layer overlaying commercial separators for RT Na−S batteries. The Ovs offer strong adsorption and abundant catalytic sites for polysulfides, while the defect concentration is finely tuned to elucidate the polysulfides conversion mechanisms. The nano‐sized perforations aid in regulating Na ions transport, resulting in uniform Na deposition. Moreover, the strategic addition of trace amounts of Ti3C2 (MXene) forms an amorphous/crystalline (A/C) interface that significantly improves the mechanical properties of the separator and suppresses dendrite growth. As a result, the task‐specific layer achieves ultra‐light (~0.1 mg cm−2), ultra‐thin (~200 nm), and ultra‐robust (modulus=4.9 GPa) characteristics. Consequently, the RT Na−S battery maintained a high capacity of 610.3 mAh g−1 and an average Coulombic efficiency of 99.9 % after 400 cycles at 0.5 C. [ABSTRACT FROM AUTHOR]

Direct synthesis of graphene on nonmetallic substrates via chemical vapor deposition (CVD) has become a frontier research realm targeting transfer-free applications of CVD graphene. However, the stable mass production of graphene with a favorable growth rate and quality remains a grand challenge. Herein, graphene glass fiber fabric (GGFF) was successfully developed through the controllable growth of graphene on non-catalytic glass fiber fabric, employing a synergistic binary-precursor CVD strategy to alleviate the dilemma between growth rate and quality. The binary precursors consisted of acetylene and acetone, where acetylene with high decomposition efficiency fed rapid graphene growth while oxygen-containing acetone was adopted for improving the layer uniformity and quality. Notably, the bifurcating introducing-confluent premixing (BI-CP) system was self-built for the controllable introduction of gas and liquid precursors, enabling the stable production of GGFF. GGFF features solar absorption and infrared emission properties, based on which the self-adaptive dual-mode thermal management film was developed. This film can automatically switch between heating and cooling modes by spontaneously perceiving the temperature, achieving excellent thermal management performances with heating and cooling power of ∼501.2 and ∼108.6 W m−2, respectively. These findings unlock a new strategy for the large-scale batch production of graphene materials and inspire advanced possibilities for further applications. [ABSTRACT FROM AUTHOR]

AbstractFiber dimension, durability/dissolution, and biopersistence are critical factors for the risk of fibrogenesis and carcinogenesis. In the modern era, to reduce, refine, and replace animals in toxicology research, the application of in vitro test methods is paramount for hazard evaluation and designing synthetic vitreous fibers (SVFs) for safe use. The objectives of this review are to: (1) summarize the international frameworks and acceptability criteria for implementation of new approach methods (NAMs), (2) evaluate the adverse outcome pathways (AOPs), key events (KEs), and key event relationships (KERs) for fiber-induced fibrogenesis and carcinogenesis in accordance with Organization for Economic Co-operation and Development (OECD) guidelines, (3) consider existing and emerging technologies for in silico and in vitro toxicity testing for the respiratory system and the ability to predict effects in vivo, (4) outline a recommended testing strategy for evaluating the hazard and safety of novel SVFs, and (5) reflect on methods needs for in vitro in vivo correlation (IVIVC) and predictive approaches for safety assessment of new SVFs. AOP frameworks following the conceptual model of the OECD were developed through an evaluation of available molecular and cellular initiating events, which lead to KEs and KERs in the development of fiber-induced fibrogenesis and carcinogenesis. AOP framework development included consideration of fiber physicochemical properties, respiratory deposition and clearance patterns, biosolubility, and biopersistence, as well as cellular, organ, and organism responses. Available data support that fiber AOPs begin with fiber physicochemical characteristics which influence fiber exposure and biosolubility and subsequent key initiating events are dependent on fiber biopersistence and reactivity. Key cellular events of pathogenic fibers include oxidative stress, chronic inflammation, and epithelial/fibroblast proliferation and differentiation, which ultimately lead to hyperplasia, metaplasia, and fibrosis/tumor formation. Available in vitro models (e.g. single-, multi-cellular, organ system) provide promising NAMs tools to evaluate these intermediate KEs. However, data on SVFs demonstrate that in vitro biosolubility is a reasonable predictor for downstream events of in vivo biopersistence and biological effects. In vitro SVF fiber dissolution rates >100 ng/cm2/hr (glass fibers in pH 7 and stone fibers in pH 4.5) and in vivo SVF fiber clearance half-life less than 40 or 50 days were not associated with fibrosis or tumors in animals. Long (fiber lengths >20 µm) biodurable and biopersistent fibers exceeding these fiber dissolution and clearance thresholds may pose a risk of fibrosis and cancer. In vitro fiber dissolution assays provide a promising avenue and potentially powerful tool to predict in vivo SVF fiber biopersistence, hazard, and health risk. NAMs for fibers (including SVFs) may involve a multi-factor in vitro approach leveraging in vitro dissolution data in complement with cellular- and tissue- based in vitro assays to predict health risk. [ABSTRACT FROM AUTHOR]

This study fabricates multiscale glass fiber/epoxy composites by incorporating graphene nanoparticles (GNPs) and zinc oxide nanoparticles (ZnO NPs) to investigate the influences of NPs on the mechanical properties of composites. The composites are manufactured using the compression molding technique with different GNP contents (i.e., 0, 0.5, 1, and 1.5 wt.%), whereas the contents of glass fibers and ZnO NPs remained the same at 40 and 4 wt.%, respectively. Their mechanical properties, chemical compositions, and fracture morphologies are then evaluated. It is found that the mechanical properties of composites improve significantly at a lower content (i.e., 0.5 wt.%) of GNPs and tend to decrease at higher contents (i.e., 1 and 1.5 wt.%). The composite is composed of 0.5 wt.% GNPs exhibit maximum tensile modulus and strength of 6.74 GPa and 230.25 MPa, and flexural modulus and strength of 16.43 GPa and 831.79 MPa, respectively, impact strength of 47.25 kJ m−2, and maximum hardness (97.96 Shore D), among all nanocomposites. Moreover, fracture morphologies reveal that composite failure is predominately caused by fiber breakage, fiber‐matrix debonding, voids, and GNP agglomeration. The outcomes of this study provide some insights to promote the application of manufactured multiscale composites in the aerospace, automotive, and marine industries. [ABSTRACT FROM AUTHOR]

Thermoplastic polycarbonate provides minimal structural weight and ductility and is a recyclable material. However, investigation of the characteristics of hybrid composites reinforced with woven glass and polycarbonate sheets is limited. This current study investigated the effect of integration of polycarbonate sheets on glass fiber‐epoxy hybrid composite performance. Non hybrid laminate was fabricated from eight layers of woven glass fiber impregnated with epoxy resin (NG). However, the hybrid samples utilized various symmetric stacking patterns which were made by alternating two processed polycarbonate (PC) sheets with six layers of woven glass fiber embedded with epoxy matrix. The manufacturing was made using the hand layup procedure. Mechanical testing includes compressive, tensile, bearing, and hardness was performed on hybrid and non‐hybrid composites. The results showed that employing PC sheets instead of fibers affect the laminate's strength, ductility, bearing capacity, and hardness. Utilization of PC sheets reduces both compressive and tensile strength. However, an enhancement in tensile, compressive, and bearing failure strain was achieved by 2.5%, 31.25% and 31.7%, respectively with hybrid composite having PC in the skin layers as compared with NG. The extent of failure damage is correlated with the position of the PC sheets in the tested samples. Highlights: Novel hybrid composites of woven glass fiber and polycarbonate sheet as reinforcement with various stacking orders were successfully prepared by the hand lay‐up method.The compressive strain of hybrid PC samples are higher than NG sample.The hybrid PC composites showed an improved bearing strength and strain performance.The influence of sample configuration on the damage mechanisms has been investigated. [ABSTRACT FROM AUTHOR]

This study looks at how erosive wear affects hybrid composites made by vacuum infusing glass and basalt fibers into an epoxy matrix. The study uses garnet abrasives and a design experiment method to test how resistant these hybrid composites are to erosion at 30°, 60°, and 90° angles of impact. The analysis included three‐dimensional profilometry and scanning electron microscopy. Results show that glass layers enhance erosion resistance, whereas basalt layers increase wear. Key quantitative findings include erosion rates and mass loss, highlighting impingement angle and erosion time as critical factors. At a 30° angle, basalt exhibited more severe wear (erosion rate: 0.8090 mg/g for 20 s) compared to glass (erosion rate: 0.5683 mg/g). Conversely, at 90°, the erosion rate for basalt decreased to 0.3643 mg/g, indicating a decreased sensitivity to this steeper angle. According to the ANOVA, impingement angle and erosion time account for 30.08% and 50.25% of the erosion rate variance, respectively. These findings advance our understanding of material behavior in hybrid composites and emphasize the strategic selection and layering of materials for enhanced durability. This research contributes to developing more sustainable composites, demonstrating natural fibers' potential to improve mechanical properties and erosion resistance. Highlights: Glass layers enhance durability against erosive forces in hybrid composites.Basalt layers accelerate erosion rates, showing a need for strategic layering.Glass fiber reinforcement significantly improves wear performance.Hybrid constructions with glass a top basalt balance flexibility and durability.Emphasizes eco‐friendly advantages of natural materials in composites. [ABSTRACT FROM AUTHOR]