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Sandwich panels are key components of many lightweight structures. They are often subjected to time-varying loads, which can cause various types of vibrations that adversely affect the functionality of the structure. That is why it is of such importance to predict the dynamic properties of both the panels and the structures made of them at the design stage. This paper presents finite element modeling of the dynamic properties (i.e., natural frequencies, mode shapes, and frequency response functions) of sandwich panels made of glass fabric impregnated with phenolic resin. The model reproducing the details of the panel structure was built using two-dimensional, quadrilateral, isoparametric plane elements. Afterwards, the model was subjected to an updating procedure based on experimentally determined frequency response functions. As a result, the average relative error for natural frequencies achieved numerically was 5.0%. Finally, a cabinet model consisting of the analyzed panels was built and experimentally verified. The relative error between the numerically and experimentally obtained natural frequencies was on average 5.9%. [ABSTRACT FROM AUTHOR]

Novel sustainable self-healing polymer composites were developed from glass fabric reinforced copolymers of eugenol/furfurylamine-derived benzoxazine resin (E-fa) and epoxidized castor oil (ECO) actuated by near-infrared (NIR) light. This research demonstrates self-healing processes triggered by NIR affected by glass fabric incorporation as well as investigates essential properties for structural skin applications in sustainable composites. Through the measurement, the reinforced glass fabrics substantially improved flexural properties, enhanced thermal stability and UV light protection of the composites. The healing mechanism and performance of the developed E-fa/ECO composites were also systematically studied. The time for damaged healing of the material triggered by heating from NIR light was found in the range of 80–152 s with the good macroscopic healing performance up to 64–86%. The results suggested that the glass fabric reinforced sustainable benzoxazine/epoxy composites possessing NIR-induced self-healing effect have a potential use in building lath applications.

One of the primary challenges faced by sandwich composites is facesheet-core debonding, which can be mitigated through various techniques such as z-pinning and stitching through the thickness. This study investigates the impact of stitching on the bending behavior of sandwich composites comprising E-glass composite facesheets and a polyurethane foam core, employing experimental, numerical, and analytical methods. Specimens were stitched at three stitch spacings of 0.5, 1, and 2 cm, with a stitch pitch of 0.8 cm and stitch seam angles of 0°, 90°, 0/90°, ±45°, 45°/90°, and ±60°. Analysis of facesheet bending stress, core shear stress, and bending rigidity of stitched specimens was conducted through three-point bending tests and compared with unstitched specimens. Results indicate that reducing stitch spacing, thereby increasing stitch density, improves bending strength, and the best bending behavior observed at ±45° stitch seam angles. Damage assessment revealed fractures and depression of the foam, wrinkles on the upper facesheet, and buckling failure of resin columns. Additionally, a theoretical model predicted bending rigidity, showing good agreement (4%–15%) with experimental data. Finite element analysis using the ABAQUS program validated the experimental results, suggesting numerical modeling as a viable method for predicting flexural properties of stitched foam core sandwich composites. [ABSTRACT FROM AUTHOR]

This research aims to analyze the influence of boron carbide particles (B4C) on the mechanical and thermo-mechanical characteristics of glass fabric reinforced epoxy to identify the suitability of fabricated composites in an automotive application. The influence of B4C up to 0.4 wt% is analyzed by mixing with epoxy resin using a magnetic stirring approach, followed by compression molding with the glass fiber reinforcement. The results revealed that the hardness of glass strengthened epoxy was increased by 38%, and the other mechanical characteristics such as tensile and flexural strength were raised by 25% and 19%, respectively, when the weight fractions of B4C were raised to 0.3 wt%. From the fractography, it was observed that the fiber pull-out and fiber fracture were the dominant failure mechanisms in the developed composites during the application. The findings of the dynamic mechanical analysis revealed that the storage and loss modulus of the composites was increased by 50% and 43%, respectively, with the 0.3 wt% of B4C showing the increase in the dynamic ability of materials even at elevated temperatures. [ABSTRACT FROM AUTHOR]

In this study, we investigated how the chemical structural properties, mechanical properties, and morphology of large‐size graphene platelets (LGPs) doped glass fabric (GF)/epoxy composites are affected by varying loading amounts of LGPs. Scanning electron microscope results revealed that the dispersion and filling effect of LGPs can improve the flowability of the resin, reducing the aggregation and shrinkage of the resin on the glass fabric surface, thereby facilitating better resin infiltration and coverage of the glass fabric surface. From the spectrum analysis, the binding of LGPs with epoxy resin was the physical combination, without new chemical groups generated during the curing process. The addition of LGPs improved the ratio of the crystalline phases in the composites, from 30.00% of the GF/epoxy to 57.50% of the GF/epoxy@2.2LGPs. Mechanical properties indicated that the composites exhibited greater tensile strength than pure GF, which progressively increased with increasing LGPs content until it reached 1.5 wt%, then the tensile strength starts to decrease. And the GF/epoxy@1.5 LGPs exhibited 136% enhancement in tensile strength compared to other carbon fillers reinforced composites, which achieved a satisfactory enhancement under relatively low loading content. Highlights: The effect of the large‐size graphene platelets (LGPs) on the properties of glass fabric (GF)/epoxy composites.Compared to the glass fabric/epoxy composite, the LGPs doped composite possessed a much higher storage modulus (E′).The LGPs doped composite exhibited 136% enhancement in tensile strength compared to other carbon fillers reinforced composites.The addition of LGPs improved the ratio of the crystalline phases in the composites. [ABSTRACT FROM AUTHOR]

With the rapid development of modern technology, more and more electronic equipment had entered people's life, causing serious electromagnetic pollution. In this study, a lightweight, ultra-thin and high electromagnetic shielding film was fabricated by copper electroless deposition after solution immersion coating method combining chitosan (CTS) and reduced graphene oxide on glass fabric (Cu/RGO-CTS-coated glass fabric). Chitosan and RGO had synergistic effect for copper deposition, enhancing electrical conductivity and electromagnetic shielding property. The prepared fabric showed superb conductivity of 8589.3 S/cm and the shielding effectiveness of the Cu/RGO-CTS-coated glass fabric showed as high as 93.6 dB at ultra-thin thickness of 92.4 μm (SSE/t = 3868.8 dB cm2 g−1). Thermal conductivity, antibacterial and hydrophobic properties were also studied. Compared with untreated glass fabric, thermal conductivity of Cu/RGO-CTS-coated glass fabric increased by 437%, protecting electronic equipment from adverse effects at high temperature. Cu/RGO-CTS-coated glass fabric had inhibitory effect on Staphylococcus aureus and Escherichia coli, which could prolong the service life and maintain the appearance of the fabric. Cu/RGO-CTS-coated glass fabric also showed hydrophobicity with self-cleaning function, making it possible for the composite material to be used in many fields such as aerospace industry, microelectronic devices, and transportation to resist electromagnetic interference in high humidity and high pollution environment. [ABSTRACT FROM AUTHOR]

Pultruded Glass Fiber-Reinforced Polymer (pultruded GFRP) composite produced by the pultrusion method has become popular in civil engineering applications due to its lightness, corrosion resistance and high strength. However, the use of the pultruded profile combining with reinforced concrete is still limited due to a lack of knowledge. Therefore, the behavior of the pultruded GFRP profile infilled with reinforced concrete beams (hybrid beams) is investigated. This study focused on the effects of stirrup spacing for the hybrid beams. Pursuant to this goal, a total of eight different beams were tested under four-point loading. One reference beam without the pultruded profile and seven hybrid beams having different stirrup spacings were considered. Moreover, the hybrid beams with and without stirrups were wrapped by unidirectional GFRP composite to investigate the effects of stirrup spacing on shear capacity of the beams strengthened by GFRP composite. The experimental findings revealed that tightening stirrups increased the load and energy dissipation capacities of the hybrid beams; however, it could not prevent brittle failure. On the other hand, wrapping hybrid beams with GFRP composite increased the load and energy dissipation capacities and also prevented brittle failure regardless of the presence of the stirrups. Therefore, it is strongly recommended that the unidirectional pultruded profiles should be strengthened with 90° GFRP wrapping to have ductile behavior. [ABSTRACT FROM AUTHOR]

Highly efficient and economical wearable piezoelectric energy harvesters are required to achieve future human‐integrated self‐powered electronics with stability. Herein, an all‐inorganic‐state fabric piezoelectric nanogenerator (FPNG) is developed for high‐performance energy harvesting using a spray‐coated lead‐free piezoceramic layer on a glass fabric. 0.5(Ba0.7Ca0.3)TiO3–0.5Ba(Zr0.2Ti0.8)O3 (BCTZ) sol–gel solution is deposited by spray coating, which is very facile and cost‐effective processing for the textile industry. It is well‐annealed and crystallized on the glass fabric endurable in high‐temperature processes. The BCTZ‐coated glass fabric is also treated by spraying silver nanowire (AgNW) solution onto both sides of the fabric to form robust electrodes. The all‐inorganic‐state FPNG can generate electrical output about the voltage of ≈3 V and the current of ≈110 nA which are high‐performance energy harvesting signals compared to previously reported fabric‐type energy harvesters. This high‐output energy harvesting results from the effective piezoelectricity of inorganic piezoceramics on the robust glass fabric. This work would open ways for future wearable self‐powered electronics integrated in general textile. [ABSTRACT FROM AUTHOR]

Micro-crack bridging and an optimal regime for dispersion of carbon nanotubes (CNTs) in the E-glass fabric reinforced polymer (GFRP) matrix are considered. The purpose of CNT dispersion in the glass fabric is to achieve the enhanced mechanical and tunable thermal/dielectric properties. The requirement for such conducting composites compared to high-cost carbon fabric is well recognized. The results are validated with the help of a theoretical model. The model relates the stiffness degradation of the composites and the existence of matrix cracks in the composites. Finite element simulation of a representative volume element of a laminate shows the effect of CNTs on the micro-cracks and the effective stiffness. The results obtained from the theoretical and finite element simulations are correlated to the experimental data and explain the increased strength due to the addition of CNT. This study shows that certain processing conditions in combination with the effect of dispersant agents reduce the porosity, residual stress and present a consistent dispersion strengthening effect with as low as 0.1 wt% CNT addition, resulting in improved tensile and compressive properties. The treatment of CNTs with ethanol reduces the Van der Waals forces among CNTs and the epoxy matrix viscosity. Enhancement in the CNT-GFRP stiffness and strength appears primarily due to effective micro-crack bridging and changes in the load transfer path. [ABSTRACT FROM AUTHOR]

This paper is concerned with the effect of core pile yarn hybridization on the low-velocity impact response of 3D integrated-woven sandwich composite panels. For this purpose, at first, hybrid yarn was produced by a co-wrapped technique that is composed of polyester and glass fibres as shell and core structure, respectively. Then, 3D-woven samples with glass and hybrid pile yarns were fabricated, and after the impregnation, the behaviour of fabricated samples under low-velocity impact was experimentally investigated. In order to characterize this new type of hybrid structure, the fabricated samples with different pile heights and pile distribution densities were subjected to low-velocity impact tests at an energy level of 8 J. The impact characteristics of all panels including the load–time and load–displacement curves, contact time, absorbed energy and extent of the damage have been studied. Also, the extent of damage is interpreted in terms of the compressive strength loss after the impact of samples. According to the results, in comparison with the homogeneous glass/epoxy composites, contact time and deflection increased in panels with hybrid pile yarn, whereas the impact load decreased for the hybrid one. On the other hand, hybrid samples have a lower impact index than the homogeneous glass/epoxy composites. The compression after impact test results showed that the residual strength in hybrid samples is higher than the glass/epoxy composites. [ABSTRACT FROM AUTHOR]

In this work, both glass fabric and jute fabric reinforced nanoclay modified soy matrix-based composites were developed and characterized. Glass fabric (60 wt.%) reinforced composite showed maximum tensile strength of 70.2 MPa and thermal stability up to 202°C, which are 82.8% and 12.2% higher than those observed with corresponding jute composite. Water absorption and contact angle values of glass-soy specimens were tested, and found composites are water stable. Biodegradation study of composites under soil burial condition revealed that glass-soy composite with 40 wt.% glass fabric lost maximum 32.6% of its original weight after 60 days of degradation. The developed glass fabric-soy hybrid composites with reasonable mechanical, thermal, and hydrolytic stability can be used in different sectors as an alternative to the nondegradable thermoplastic reinforced glass fabric composites. [ABSTRACT FROM AUTHOR]

Recently, high tensile fibres composite laminates (i.e. glass composite laminates) have been widely used in the civil and military applications due to their superior properties such as lightweight, fatigue and corrosion resistance compared to metals. Nevertheless, their brittle fracture behaviour is a real downside for many sectors. In the present study, the impact of the hybridisation of Kevlar woven layers with glass woven layers on the reducing the strain failure problem in pure glass woven laminates is investigated. In this work, multi-layers Kevlar-glass with different stacking sequences have been used to prepare the hybrid composite laminates using vacuum–assisted resin moulding method. The influence of the layers hybridisation on the mechanical performance of composites laminates was investigated using tensile strength tests. Furthermore, finite element analysis is performed to analyse the mechanical response of the hybrid composite laminates using Abaqus software. The elastic constants of woven fabric layers in the numerical study were predicted through geometric model based on the textile geometry and analytical method in order to assert accuracy of the predicted elastic constants. The experimental results showed that the hybrid composite laminates tend to fail more slowly than glass woven laminates, which illustrates low strain to failure. In the theoretical part of the study, it was found that the proposal model can be useful to capture the mechanical behaviour and the damage failure modes of hybrid laminates. Thus, the catastrophic failure can be avoided in these laminates. [ABSTRACT FROM AUTHOR]

In this paper, composite and hybrid composite materials were prepared using the hand lay-up method, with carbon, glass, and Kevlar fabrics as the reinforcing materials and epoxy as a matrix. The tensile test was performed to determine the optimal ratio of epoxy resin in carbon fabric/epoxy, glass fabric/epoxy, and Kevlar fabric/epoxy composites in terms of tensile properties. It was found that the optimal ratio of epoxy in terms of tensile properties to impregnate the used Kevlar fabric, glass fabric, and carbon fabric was around 45%wt, 3%wt, and 30%wt, respectively. The effect of fabric content and stacking sequences, with a fixed epoxy content, on the hybrid composites' tensile properties were also investigated. The tensile properties of the prepared composites were compared to determine the most favorable preparation conditions for obtaining a hybrid laminate that has high tensile properties and is suitable for a wide range of applications at a low cost. [ABSTRACT FROM AUTHOR]

The interyarn friction properties of fabrics can be enhanced by appropriate surface treatment of fibers. This study focuses on evaluating the interyarn friction properties of Kevlar and Glass fabrics that were coated with ZnO nanowires through different growth cycles. ZnO nanowires were coated onto woven Kevlar and Glass fabrics through a low temperature hydrothermal solution method. Longer growth time coupled with periodic refreshing of growth solution and washing of fabrics was found to be a favorable condition for uniform and precipitate free growth of ZnO nanowires. The effects of ZnO nanowire coating on the tensile and interyarn friction properties of fabrics were measured. In general, after ZnO nanowire coatings, Kevlar fabrics remained equally flexible as that of bare fabric while Glass fabrics became relatively stiff and brittle. The interyarn friction properties of Kevlar fabrics were found to be high under 100 N transverse tension while the transverse tension was found to have negligible or insignificant effect on the interyarn friction properties of Glass fabrics that were used in this research. Compared to bare fabric, Kevlar fabric coated with ZnO nanowires for extended duration showed 266% and 293% increase in yarn pull out load and energy, respectively under 100 N tension. Compared to bare fabric, Glass fabric coated with ZnO nanowires for extended duration showed 517% and 376% increase in yarn pull out load and energy, respectively under 5 N tension. These significant improvements in interyarn friction properties were attributed to mechanical interlocking and accumulation of ZnO nanowires at the intersection of yarns. [ABSTRACT FROM AUTHOR]

The location of defect formed in the final composite is identified using sensor data. Herein, we report the development of an online process monitoring system for vacuum-assisted resin transfer molding (VARTM) process using large area graphene coated in-situ fabric sensor. Besides imparting excellent mechanical properties to the final composites, these sensors provide critical information during the composite processing including detecting defects and evaluating processing parameters. The obtained information can be used to create a digital passport of the manufacturing phase to develop a cost-effective production technique and fabricate high-quality composites. The fabric sensor was produced using a scalable dip-coating process by coating 1-, 3- or 5-layers of thermally reduced graphene oxide (rGO) onto glass fabric surface according to the number of dips of the fabrics into GO solution. 5 electrode pairs were placed in the horizontal and vertical directions on the area of each coated fabric sensor before placing it inside the VARTM setup. The electrical resistances from all electrode pairs were simultaneously and continuously recorded during distinct stages of the VARTM process to determine the relative conductance. During the vacuum cycle, the range of relative conductance increased with the number of coated rGO layers, with the 5-layer rGO-coated sensor showing the highest conductance range of 16.9 %. Additionally, it was observed that the 5-layer coated sensor showed a consistent decrease in conductance during the infusion phase due to the fluid flow pressure dominating the resin electrical conductivity. Most importantly, physical parameters such as infusion time, flow front location, race-tracking and dry spots were monitored in-situ., (© 2024 Wiley-VCH GmbH.)

Composite materials have been prepared using Kevlar and glass fabrics as reinforcement materials and epoxy resin as a matrix. The best ratio of epoxy in the Kevlar fabric/Epoxy and glass fabric/epoxy composites was determined in terms of their mechanical properties. Then, surface treatments of Kevlar fabric have been done using phosphoric acid to investigate their effect on Kevlar fabric/Epoxy composite material mechanical properties. The impact and tensile properties of the Kevlar/Epoxy composite material have been improved, and their Young's modulus increased by 38%. After that, hybrid composite materials were prepared using Kevlar and glass fabrics and epoxy. The mechanical properties of the prepared hybrid composite materials have also been studied (impact and tensile testing) in relation to composition and surface treatments. Finally, the results have been studied in order to determine the optimal preparation conditions for obtaining suitable composite material in terms of weight, mechanical properties, and cost. [ABSTRACT FROM AUTHOR]

The surfaces of glass fabric (GF) were attached with multi-walled carbon nanotubes (MWCNTs) through electrostatic absorption and physical deposition methods, thus the MWCNTs attached GF reinforced epoxy composites based on the GF-d-CNTs and GF-a-CNTs multiscale reinforcements were prepared by vacuum-assisted resin infusion molding (VARIM) technique. Tensile properties, flexural properties, interlaminar shear strength, dynamic viscoelasticity and microstructure of composites were measured and characterized using the static and dynamic mechanics methods, scanning electron microscope, Fourier transform infrared spectroscopy, respectively. The results show that the network structures of MWCNTs attached GF, like "nanobarbed wires", are identified to improve the fiber/matrix adhesion strength and the toughness of resin through the micromechanical interlocking, which exhibits an evident enhancement in glass transition temperature (Tg). As compared to the GFRP without MWCNTs, the mechanical properties of GF-d-CNTs composites are significantly higher, the tensile strength and modulus, flexural strength and modulus and interlaminar shear strength of GF-d-CNTs composites increased by 14.5%, 37.9%, 26.2%, 36.6% and 31.5%, respectively. Moreover, the Tg of GF-a-CNTs composites is improved by 8.9℃.

In this work, graphene is prepared by reduction of graphene oxide. The graphene obtained is used as the reinforcing nanofiller in an epoxy matrix. The incorporation of 0.1 wt.% loading of graphene in an epoxy matrix shows the maximum increase in the flexural properties as compared to the pure epoxy. It is due to good dispersion of graphene and interaction between C-N group of epoxy and C=O group of graphene. The loading of 0.1 of wt.% graphene in epoxy is used to prepare the glass fabric reinforced multiscale nanocomposites. This multiscale nanocomposite shows an enhancement in flexural properties. It is due to the mechanical interlocking associate with random dispersion of graphene in epoxy resin. In addition, glass fabric is coated with polyvinylpyrrolidone (PVP) modified multiwalled carbon nanotubes (MWNT) and its multiscale nanocomposites show the enhanced flexural strength. The increase in flexural strength is due to mechanical keying associated with the rough surface obtained with the coating of MWNT over glass fabric. Further, with an addition of 0.1 wt.% of graphene and MWNT coated glass fabric in epoxy multiscale nanocomposites, flexural properties enhancement are highest. It is due to the combined effect of mechanical keying and mechanical interlocking associated with graphene dispersion and rough surface of MWNT coat over glass fabric. In addition, the toughness of the MWNT coated glass fabric and graphene filled epoxy multiscale nanocomposites increases due to the mobile epoxy chains contributing towards the energy absorption. It is observed that the epoxy chains in contact with PVP coated MWNT are mobile as confirmed from dynamic mechanical analysis (DMA) studies. Thus, due to mechanical interlocking, the mobility of epoxy chains and mechanical keying; the flexural modulus, flexural strength, flexural toughness, and storage modulus obtained are highest for the graphene and MWNT coated glass fabric in epoxy multiscale nanocomposites. [ABSTRACT FROM AUTHOR]

Inspired by the highly ordered structure and excellent mechanical performance of nacre, surface functionalization of graphene (GE) has been prepared, polytetrafluoroethylene (PTFE)/glass fabric (GF) composites modified by introducing the GE and in vertical immersion method. The results show the negatively charged poly(sodium-p-styrenesulfonate) coat on the GE and prevent aggregation, and thus form stable dispersions. The tensile strength and toughness of PTFE/GF composites achieve the maximal value of 25.1 MPa and 20.2 MJ/m3, respectively, as well as the surface resistivity achieve the minimum value of 1000 Ω cm. With the incorporation of GE, the mechanical properties and electrical conductivity of PTFE/GF composites improve significantly. Moreover, modified GE further increases the properties of PTFE/GF composites. Modified GE shows better dispersion effect than pure GE. [ABSTRACT FROM AUTHOR]

Featured Application: Optimisation of textile reinforced concrete (TRC) composites for new constructions and for the seismic retrofitting of existing buildings. Textile reinforced concrete (TRC) is a promising high-performance material that has been employed with success in new constructions, as well as a strengthening layer of existing structural components. In this work, we document the optimisation procedure of textile-based composites for new construction and for the seismic retrofitting of under-reinforced concrete elements and masonry buildings. The study, aimed at maximising the material performances avoiding waste of economic resources, was addressed by means of a series of uniaxial tensile tests conducted on a wide set of alkali-resistant (AR) glass fabrics and TRCs. The samples differed in terms of cement-based matrices, embedded textiles and addition of dispersed microfibers. The results highlight the effects of fabric characteristics and introduction of short fibres on the mechanical behaviour, proposing novel comparison parameters based upon the load bearing capacity and the deformation response of the composites. The application of simplified analytical models borrowed from the literature finally revealed the limitations of the available predictive approaches, suggesting future lines of investigation. [ABSTRACT FROM AUTHOR]

A generic static and impact experimental procedure has been developed in this work aimed at improving the stability of glass fabric reinforced epoxy shell structures by bonding with axial stiffeners. Crashworthy structures fabricated from composite laminate with stiffeners would offer energy absorption superior to metallic structures under compressive loading situations. An experimental material characterisation of the glass fabric reinforced epoxy composite under uni-axial tension has been carried out in this study. This work provides a numerical simulation procedure to describe the static and dynamic response of unstiffened glass fabric reinforced epoxy composite shell (without stiffeners) and stiffened glass fabric reinforced epoxy composite shell (with axial stiffeners) under static and impact loading using the Finite Element Method. The finite element calculation for the present study was made with ANSYS®-LS-DYNA® software. Based upon the experimental and numerical investigations, it has been asserted that glass fabric reinforced epoxy shells stiffened with GFRP stiffeners are better than unstiffened glass fabric reinforced epoxy shell and glass fabric reinforced epoxy shell stiffened with aluminium stiffeners. The failure surfaces of the glass fabric reinforced epoxy composite shell structures tested under impact were examined by SEM.

Abstract: The porosity and the heat resistance of the composites based on a homogeneous or heterogeneous aluminoborophosphate binder reinforced by glass, basalt, and carbon fabric are studied. The results of macrostructural analysis of the composites fabricated by vacuum infusion and pressing are presented. [ABSTRACT FROM AUTHOR]

The effects of mixed metal oxides (CexZr1−xO2) nanoparticle dispersion on the mechanical properties and fracture mechanisms of epoxy polymer matrix and its composite with glass fiber system are reported in this paper. CexZr1−xO2 nanoparticles are synthesized using sol-gel method, and its crystallinity is optimized. Epoxy nanocomposites are synthesized by a dispersion technique, and the compressive properties are optimized. The glass transition temperature has been improved. Epoxy with 5 wt.% of Ce0.75Zr0.25O2 shows optimal results with an increase of 17.4% in compressive modulus, and an increase of 23.4% in compressive strength with respect to those of neat epoxy. This improvement attributes to higher strength of shearing of polymer during the fracture of the nanoparticle interface. Micro-crack kinks at the interfaces can further delay fracture under compression. E-glass fabric-reinforced 5 wt.% Ce0.75Zr0.25O2-epoxy nanocomposite also shows improvement in the mechanical properties via nanoscale interface with fibers. This type of ceramic nanocomposites has useful applications in thermal/electrical insulations besides improving the compressive/buckling properties. [ABSTRACT FROM AUTHOR]

The present study investigates the influence of maleic anhydride compatibilizer on the mechanical and thermal behavior of glass fiber reinforced polypropylene composites. The composites were prepared by hot compression molding using novel glass fabric and functionalized polypropylene. The tensile, open-hole tensile, dynamic mechanical analysis and differential scanning calorimetry tests were performed as per ASTM standards to characterize the prepared composites. The experimental test results revealed that the increase in maleic anhydride concentration initially increased the tensile strength and open-hole tensile strength by 20.69% and 9.8%, respectively, and then decreased. Dynamic mechanical analysis showed the higher thermal stability of thermoplastic composites and also confirmed the enhancement of both the modulus, due to the addition of glass fiber. Differential scanning calorimetry results had shown a significant change in the degree of crystallinity behavior. It was observed by scanning electron micrographs that the functionalized polypropylene has improved the interfacial bonding between the constituent materials and was ascertained by Fourier transform analysis. [ABSTRACT FROM AUTHOR]

With the rapid development of industrialization, the deterioration of water resources, especially oily wastewater pollution, is becoming a worldwide threat, because it is severely harmful to biological and human safety. Recently, porous meshes with superhydrophilicity and underwater superoleophobicity have attracted significant attention due to their low oil adhesion and selective oil-water separation. However, simple, environmentally friendly, low-cost, multifunctional and facile scaled-up materials are still urgently in demand. Here, a natural polymer-based hydrogel prepared by konjac glucomannan (KGM) was coated on glass fabric, a kind of engineering material. The resulting hydrogel-coated glass fabric not only shows excellent performance of water removal from oil-water mixture but also can remove organic dyes and heavy metals in water simultaneously during the oil-water separation process. In addition, due to the strong hydration capacity, the DKGM hydrogel-coated glass fabric shows underwater ultra-low-oil-adhesive superoleophobicity to viscous oils, which means it is self-cleaning with respect to oils in an aqueous environment and can be easily recycled for long-term use. Importantly, the superhydrophilicity and underwater superoleophobicity of these hydrogel-coated glass fabrics were maintained under various harsh conditions. The low-cost, biodegradable and environmentally friendly preparation, resistance to harsh conditions and multifunctional applications properties make these hydrogel-coated glass fabrics hold great potential for purifying oily wastewater. [ABSTRACT FROM AUTHOR]

Textile reinforced concrete (TRC) is a promising high-performance material that has been employed with success in new constructions, as well as a strengthening layer of existing structural components. In this work, we document the optimisation procedure of textile-based composites for new construction and for the seismic retrofitting of under-reinforced concrete elements and masonry buildings. The study, aimed at maximising the material performances avoiding waste of economic resources, was addressed by means of a series of uniaxial tensile tests conducted on a wide set of alkali-resistant (AR) glass fabrics and TRCs. The samples differed in terms of cement-based matrices, embedded textiles and addition of dispersed microfibers. The results highlight the effects of fabric characteristics and introduction of short fibres on the mechanical behaviour, proposing novel comparison parameters based upon the load bearing capacity and the deformation response of the composites. The application of simplified analytical models borrowed from the literature finally revealed the limitations of the available predictive approaches, suggesting future lines of investigation.

In order to evaluate the electromagnetic (EM) absorption and shielding effects in near-field and far-field regions, the FeCoNi-coated glass fabric/polycarbonate composite sheets were fabricated. The composite sheets were composed of the laminated structure, which has one or two ply-FeCoNi-coated glass fabrics with or without Ni grid in polymer matrix. The evaluation of EM absorption and shielding behaviors was measured by using a microstrip line and a shielded loop antenna, which is based on IEC62333 in near field and rectangular waveguide at the X-band region in the far-field region. The power absorptions were up to about 86% at 10 GHz. The inter-decoupling effect for FeCoNi-coated glass fabric with Ni grid in composite exhibited about 45 dB at around 1.3 GHz, which is comparable to that of a conductive Cu foil. The shielding effectiveness was obtained over 70 dB at the X-band region for FeCoNi-coated glass fabric with Ni grid composite sheets. [ABSTRACT FROM AUTHOR]

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This paper reports the low velocity impact behavior of thermoplastic laminated structures based on thermoplastic polyurethane reinforced with woven glass fiber highlighting effects related to sample thickness and test temperature with the aim to verify their potential applications. Plaques obtained by film stacking and compression molding technologies are tested using an instrumented falling dart machine at room temperature, −25 °C and −50 °C. Impact results are reported in terms of typical load-deflection and energy-time curves, but also discussed with reference to the well known ductility index (DI) parameter. As expected, the cooling is reflected in an increased stiffness of tested specimens and their higher propensity to the damage. Increases of plate thickness and reductions of the test temperature lead to enhanced friction phenomena at the material-dart contact, responsible of significant deviations from well established semi-empirical models about the Hertz contact force and the penetration energy. Finally, no delamination phenomena seem to be verified for all investigated samples as supported by visual inspections of front and rear impacted areas. [ABSTRACT FROM AUTHOR]

Glass fabrics were used to fabricate boron nitride nanotubes (BNNTs) with a broad diameter range through a combined chemical vapor deposition and self-propagation high-temperature synthesis (CVD-SHS) method at different holding times (0min, 30min, 90min, 180min and 360min). SEM characterization has been employed to investigate the macro and micro structure/morphology changes of the glass fabrics and BNNTs in detail. SEM image analysis has provided direct experimental evidences for the rationality of the optimized self-cracking catalyst VLS growth mechanism, including the transformation situations of the glass fabrics and the BNNTs growth processes respectively. This paper was the further research and compensation for the theory and experiment deficiencies in the new preparation method of BNNTs reported in our previous work. In addition, it is likely that the distinctive self-cracking catalyst VLS growth mechanism could provide a new idea to preparation of other inorganic functional nano-materials using similar one-dimensional raw materials as growth templates and catalysts. [ABSTRACT FROM AUTHOR]