Traditional Glass Fiber Research Articles

A seaweed-inspired separator for high performance Zn metal batteries: Boosting kinetics and confining side-reactions

Uncontrolled dendrite growth, sluggish reaction kinetics, and drastic side reactions on the anode-electrolyte interface are the main obstacles that restrict the application prospect of aqueous zinc-ion batteries. Traditional glass fiber (GF) separator with chemical inertness is almost ineffective in restricting these challenges. Herein, inspired by the ionic enrichment behavior of seaweed plants, a facile biomass species, anionic sodium alginate (SA), is purposely decorated on the commercial GF separator to tackle these issues towards Zn anode. Benefiting from the abundant zincophilic functional groups and superior mechanical strength properties, the as-obtained SA@GF separator could act as ion pump to boost the Zn2+ transference number (0.68), reduce the de-solvation energy barrier of hydrated Zn2+, and eliminate the undesired concentration polarization effect, which are verified by experimental tests, theoretical calculations, and finite element simulation, respectively. Based on these efficient modulation mechanisms, the SA@GF separator can synchronously achieve well-aligned Zn deposition and the suppression of parasitic side-reactions. Therefore, the Zn||Zn coin cell integrated with SA@GF separator could yield a prolonged calendar lifespan over 1230 h (1 mA cm−2 and 1 mAh cm−2), exhibiting favorable competitiveness with previously reported separator modification strategies. Impressively, the Zn-MnO2 full and pouch cell assembled with the SA@GF separator also delivered superior cycling stability and rate performance, further verifying its practical application effect. This work provides a new design philosophy to stabilize the Zn anode from the aspect of separator.

Improving dynamic energy absorption performance and stability loss prediction of an all-PET sandwich structure through artificial neural networks

Abstract One key characteristic that is frequently studied in composite sandwich structure mechanics is low-velocity impact performance. Single polymer composites present higher ductility when compared to traditional glass fibre and carbon fibre reinforced plastic composites (GFRP, CFRP), which makes them strong candidates for impact energy absorption. These lightweight structures are also fully recyclable due to their all-PET constituents, an important aspect when considering possible applications. In this paper an existing second order composite SrPET and PET foam sandwich structure (self-reinforced poly-ethylene terephthalate matrix and fibre) is numerically investigated for optimal structural design configuration under out-ofplane, low velocity, dynamic loading. The study explores the parametric geometry interdependencies of the structure’s configuration with respect to its energy absorption potential. The results are then compared to the quasi-static loading performance behaviour studied by M.N. Velea et all [1]. This work provides a deeper understanding of how geometry configurations can influence energy absorption capabilities highlighting structural strengths and weaknesses while exploring non-equilateral triangle configurations. The Design Space Exploration (DSE) is carried out by using an optimization algorithm for a dynamic out of plane 3D impact simulation based on the finite element (FE) method software. The synergy between DSE and FE generates a guided simulation loop that can successfully be used to train a neural network to predict the dynamic behaviour of different geometric configurations from the exploration space. Based on the data samples obtained, an artificial neural network (ANN) is built to predict the energy absorption capacity for a given set of structural design parameters, useful in experimental validation test cases.

Compression Molding of Low-Density Polyethylene Matrix/Glass-Fiber-Reinforced Thick Laminates.

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.

Towards sustainable composites: Evaluation of mechanical properties, erosion behavior and applications of natural fiber-epoxy composites

Sustainable production and consumption, carried to materials and engineering applications, translates to a need for recyclable, reusable, and/or biodegradable materials. With its lower cost, lighter weight, and less carbon footprint compared to traditional glass and carbon fiber composites, natural fiber-reinforced composites are drawing more attention from the scientific community and the industrial sector. The natural fiber’s high variability and relatively inferior mechanical properties necessitate comprehensive characterization for accurate evaluation of their properties and fitness for different applications. In this research, various locally grown natural fibers (Flax, Jute, and Luffa) were sourced, characterized, and used to synthesize natural fiber-reinforced epoxy composites. The tensile, flexural, impact properties, and erosion resistance of the composites was evaluated. Compared to the other natural fiber composites, the Jute-Epoxy composite achieved the highest tensile strength and tensile modulus with 31 MPa and 4.8 GPa respectively; Jute-Epoxy also achieved the highest flexural strength and flexural modulus, with and 60 MPa and 2.4 GPa respectively. This superior mechanical performance is due to the relatively high strength of the Jute fiber and its high adhesion to the matrix, which is supported by fractographic evidence. Luffa-Epoxy composites in general had the lowest properties of all the tested materials. The erosion test results showed that the Jute-Epoxy composites had the highest erosion resistance of all the tested materials; with 30% more erosion resistance compared to glass-fiber epoxy composites. Based on the experimental results of the investigation and similar previous research, the current and potential applications of natural fiber composites were discussed.

Achieving highly stable sodium metal batteries with self-adapting and high-ionic-mobility ceramic fiber membranes

Tough issues like sodium (Na) dendrite growth and poor anode reversibility hinder the practical application of sodium metal batteries (SMBs) with moderate liquid electrolytes. To settle these problems, using a smart self-adapting Al2SiO5 ceramic fiber (CF) membrane is demonstrated to enable homogeneous Na depositions and inhibit the dendritic growth. This inorganic membrane itself has superb thermal stability, high ionic mobility (Na+ transference number: 0.65) and electrolyte wettability over traditional glass fiber (GF) or polymeric ones, guaranteeing the low voltage polarization (14 mV) and long-cyclic lifetime (over 600 h) in symmetric cells testing. Notably, aluminous components in CF membranes would interact with F-based molecules in the electrolyte phase, thereby releasing some Al3+ species that can be electrochemically deposited onto the anodic interface. The packed (+)Na3V2(PO4)3|CF|Na(−) full SMBs exhibit far superior cyclic stability (capacity retention over 78.7 % after 600 cycles at 1C) than other counterparts. The in-situ detection/postmortem analysis reveal that Al/F-based inorganics formed in as-built SEI layers play a vital role in Na metal anode protection. This work may provide a viable strategy to overcome the constraints of high-energy SMBs in practical applications.

Unsaturated polyester resin synthesis for enhanced fiber-reinforced composite performance

This research aims to enhance traditional glass fiber composites by utilizing a mediumreactive unsaturated polyester resin (UPR) synthesized from ortho-phthalic anhydride. The UPR is formulated using unsaturated acids, glycols, and styrene monomers, with the reaction tailored to improve mechanical properties beyond those of standard commercial resins. The liquid resin's properties are evaluated for manufacturing viability, and its solidified form demonstrates superior performance compared to industrial benchmarks. The composite, produced via the hand layup technique, features a reduced resin-to-glass fiber ratio. Mechanical property tests confirm its robustness. Additionally, scanning electron microscopy (SEM) analysis reveals the microstructural characteristics to study the UPR performance.

Revolutionizing transportation composite structures: Lightweight, sustainable, and multi-scale hybrid design through waste tire-driven graphene, hemp fiber, and bio-based overmoulding

The pursuit of lightweight, environmentally friendly composite structures in transportation is crucial for minimizing ecological footprints and promoting energy-efficient manufacturing techniques. This study presents a novel approach by replacing traditional long glass fiber reinforced homopolymer polypropylene (homoPP) compounds with short hemp fiber reinforced homoPP, incorporating graphene nanoplatelets (GNP) derived from recovered carbon black via waste tire pyrolysis, resulting in a remarkable 15% weight reduction. With new compound formulation by adjusting the amounts of compatibilizer and GNP, injection moulding process was integrated with overmoulding process by using bio-based UD prepregs to enhance the adhesion of injected part and interfacial interaction by decreasing the stress concentrations in the structure. This novel hybrid composite design having 40 wt% hemp fiber, 1.0 wt% GNP and 2.7 wt% compatibilizer provided to improve flexural modulus and strength by 169% and 67.9%, respectively, compared to neat homoPP. The overmolding process employed bio-based natural fibers reinforced UD tapes as inserts, leading to an impressive enhancement of 211% in tensile modulus and 93.6% in strength, further surpassing the performance of neat homoPP. This work not only achieves the conversion of conventional composite structures into recyclable, sustainable thermoplastic composites but also introduces multi-scale reinforcements with customizable functionality, demonstrating a significant step forward in the development of environmentally conscious materials and manufacturing methods by adopting Life-Cycle Assessment (LCA) methodology regarding the sustainability of the newly developed composites.

Nanocellulose-reinforced air filter with gradient hierarchical structure for highly effective and reuseable antibacterial air filtration

Since the outbreak of COVID-19, microbial pollutants in the air have attracted people's attention. Existing air filters can only intercept microorganisms but cannot inactivate them. Thus, there is an urgent need to design air filters with antibacterial properties. In this study, we used vacuum-assisted filtration to adjust the pore structure of the traditional glass fiber air filter with cellulose nanofiber (CNF) and tempo-oxidized nanocellulose (TNF), and constructed a graded air filter (GCT) with gradient pore structure and Janus structure. At the same time, the addition of nanofibers increased the mechanical properties of the glass fiber air filter. Finally, the filters were endowed with good photothermal properties and stable antibacterial properties by adding antibacterial agents from previous studies (GCT/Ag-3). GCT/Ag-3 responded under near-infrared light, achieving a 99.9 % antibacterial rate against E. coli and S. aureus within 90s, and maintaining this high efficiency after 6 cycles, which provides a feasibility for the design of antibacterial air filter.

Study onThe Moisture Absorption Properties of jute Fiber Reinforced Composites

Fiber-reinforced composites (FRP) have gradually become an important direction for the development of new materials due to their various excellent properties since their development. However, traditional glass fibers, carbon fibers, basalt fibers, etc. have various problems such as cost and environmental pollution, in contrast to natural crop fibers which are low-priced, widely available and environmentally friendly. In order to verify the service characteristics of jute fiber, one of the representatives of natural fibers, in complex environments, jute fiber reinforced composite laminates were prepared using Vacuum Assisted Resin Infusion (VARI) process, and the moisture absorption properties of the laminates were investigated and the influence law and mechanism of four temperatures and two fiber plies on the water absorption and diffusion properties of the laminates were analyzed. The results show that: the moisture absorption process of the laminate conforms to Fick’s second law, but the applicability of Fick’s second law decreases as the temperature increases; the moisture absorption rate of the laminate increases exponentially as the temperature increases, but the saturation rate decreases, and the corrosion rate of the laminate increases; the increase in the number of plies of the laminate affects the increase in the time to reach the saturation rate of the laminate, and the diffusion coefficient increases; the service performance of 6-layer laminate is better in the same hygrothermal environment.

Dimerizing Lawsone into Bis-lawsone to Counter Solubility and Attain Facile Zn2+ Ion Diffusion for Stable Capacity in Aqueous Zinc-Ion Batteries

Given the higher volumetric capacity of Zn (5853 mAh cm−3), aqueous zinc-ion batteries can be considered as alternatives to lithium-ion batteries for energy storage applications. Here we focus on redox-active, non-toxic, and eco-friendly organic materials with quinone moiety, i.e., Lawsone (LS) and its dimer Bis-lawsone (BL), as a cathode material for Zn-ion batteries. The reversibility of LS and BL is confirmed by cyclic voltammetry between 0.3 and 1.6 V in zinc sulfate and zinc triflate electrolytes. The electrochemical performance of BL in the zinc triflate electrolyte is improved by the reduction in the solubility of BL in the electrolyte and improvement in Zn2+ diffusion in the BL matrix. Besides, it is known that Zn electrodes passivate better in zinc triflates, which contributes to improved plating/stripping of Zn. The dimerization strategy counteracts solubility and facilitates the diffusion of Zn2+, resulting in a stable charge–discharge with a specific capacity of 200 mAh g–1. The cell attained 77% of the theoretical capacity at a current density of 100 mA g–1. Zn-BL cells show fast kinetics and reversibility for up to 760 cycles retaining 85% of initial capacity despite the partial solubility of BL in electrolytes. In addition, the Nafion-212 membrane is introduced as a separator instead of a traditional glass fiber separator. The negatively charged backbone of Nafion helps eliminate the crossover problem by coulostatic repulsion with negatively charged BL and LS.

Effect of accelerated weathering on the performance of natural fibre reinforced recyclable polymer composites and comparison with conventional composites

This work investigated the long-term performance of unidirectional (UD) flax fibre reinforced recyclable polymer composites (FFRPs), after accelerated weathering for a total of 56 days, in laboratory environment. The employed recyclable polymer matrices were a bio-based epoxy and a liquid thermoplastic acrylic resin. The performance of the developed composites, were compared with traditional UD glass fibre composites (GFRPs), employing a standard petro-based epoxy resin, in terms of flexural and viscoelastic properties, while visual inspection and Scanning Electron Microscopy (SEM) were employed to investigate further the effects of ageing after exposure. It was revealed that the reinforcing fibres dominated the performance of the composites after ageing, whilst the choice of polymer matrix exhibited less influence.

Hierarchical porous separator with excellent isotropic modulus enabling homogeneous Zn2+ flux for stable aqueous Zn battery

Low-cost, high-safety aqueous Zn-ion batteries show promise for large-scale energy storage, but the unsatisfactory cycling stability of Zn anodes and the lack of a suitable hydrophilic separator for rechargeable aqueous Zn batteries limit their practical applications. In this work, we report a scalable method for the preparation of a homogenous polyvinylidene fluoride-lithium bistrifluoromethanesulfonimide (LiTFSI) (PVDF-Li)-based separator for aqueous Zn batteries. The homogenously mixed LiTFSI salt interrupted the crystalline framework of PVDF with excellent mechanical strength and led to hierarchical pore structures for the rapid and uniform Zn2+ flux through the separator. Meanwhile, the PVDF-Li separator exhibited excellent wettability toward aqueous Zn electrolytes. With the advanced PVDF-Li separator, the Zn dendrite growth can be suppressed greatly, showing an improved cycle life. The Zn||V2O5 full cell with PVDF-Li separator exhibited a 27% higher initial capacity (324 mA h g−1) and considerably better capacity retention than the traditional glass fiber separator due to the uniform reaction on the V2O5 cathode and Zn anode sides. This work provides new insights into the development of high-performance aqueous batteries by regulating the reactions on the cathode and anode through functional separators.

Sustainable Basalt Fibers vs. Traditional Glass Fibers: Comparative Study on Thermal Properties and Flow Behavior of Polyamide 66-Based Composites

In this work, basalt fibers (BF) have been investigated as possible natural and sustainable replacements for the common synthetic mineral filler—glass fibers (GF)—used in polyamide 66 matrix (PA66). Composites have been prepared at two different fiber concentrations (15 and 25 wt.%, respectively) by melt blending. The developed systems have been mainly characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), capillary rheology, and scanning electron microscopy (SEM). The kinetic parameters to thermal degradation through the Coats–Redfern method allowed us to attest a negligible effect of fiber type on thermal stability of the developed systems. Composites incorporating 15 wt.% of fiber content possessed the highest activation energy (≥230 kJ/mol). The introduction of BF and GF in PA 66 polymer, regardless of content, always led to an increase in crystallization and melting temperatures, and to a similar reduction in crystallinity degree and glass transition temperature. The shear viscosity of the basic polymer increased by the addition of fillers, particularly at low shear rate, with a pronounced effect in the case of basal fibers. A slightly higher shear thinning behavior of BF/PA66 with respect to GF/PA66 composites was confirmed by fitting the flow curves through the power law model. Finally, a worsening in fiber dispersion, by increasing the content in the matrix, and a weak compatibility between the two phases constituting the materials were highlighted through SEM micrographs.

The feasibility of continuous basalt fibre‐reinforced polymer application to composite cross‐arms

AbstractComposite cross‐arms have the advantages of high lightning resistance but impose onerous requirements on mechanical and insulation reliability. Traditional glass fibre composites fail to meet the needs of practical applications. Basalt fibre exhibits better mechanical properties and stability than glass fibre and has potential application value. This study aims to evaluate the feasibility of its application to composite cross‐arms. The mechanical, electrical, and physical properties of basalt fibre‐reinforced polymer (BFRP) were investigated and compared with glass fibre‐reinforced polymer (GFRP). The results indicate that BFRP has better thermal stability and mechanical properties than GFRP. Among them, the temperature at the maximum weight loss rate of BFRP is 14°C higher than that of GFRP, and the tensile and flexural modulus of BFRP is 43% and 29% higher than those of GFRP. Furthermore, the dielectric losses of BFRP and GFRP at 50 Hz are 2%, and the breakdown field strength is 22 kV/mm, both of which have the same insulation properties. BFRP meets the requirements of composite cross‐arm for quality and reliability to ensure the safety and stability of transmission lines. However, the interlaminar shear test and SEM show weak interfacial bonding strength between basalt fibre and resin. Furthermore, micro‐computed tomography scanning of BFRP and GFRP and 3D construction of their internal microstructures indicate that the pore defect content of BFRP reaches 0.034%, which far exceeds that of GFRP. These findings show that the wettability and adhesion between basalt fibre and resin must be improved. Developing special sizing agents for basalt fibre is necessary further to improve the mechanical and electrical properties of BFRP.

Effect of Sizing Agent on the Mechanical, Thermal, and Electrical Performance of Basalt Fiber/Epoxy Composites.

Basalt fiber and its resin composites have gradually supplanted traditional steel and glass fiber composites due to their superior strength, heat resistance, and corrosion resistance. However, basalt fiber still has significant flaws that restrict the functionality and use of its composites, such as less active functional groups and poor resin adherence. This study examines the effects of sizing agent on the characteristics of basalt fiber/epoxy resin composites. Epoxy resin emulsion and acrylate emulsion are employed as the primary auxiliary film-forming agents in this study. Polyurethane emulsion with various content levels is also used. The findings indicate that a 1% wt. of polyurethane emulsion concentration produces the greatest results, increasing the composite’s flexural strength, flexural modulus, tensile strength, and interlaminar shear strength by 122%, 34.0%, 102%, and 10.2%, respectively. At the same time, the storage modulus and Tg of the material will decrease. In addition, the breakdown strength can be raised by 112%, and insulation parameters such as leakage current and dielectric loss factor can be decreased by 26.4% and 15.6%, respectively. The effect of sizing agent B is the best.

Energy consumption performance optimization of PTFE HEPA filter media during dust loading through compositing them with the efficient filter medium

• Composite PTFE media designed to reduce resistance growth and energy consumption. • Windward efficient media affect significantly performance of composite PTFE media. • Eligible loading aerosols for HEPA media have mass mean diameter less than 0.4 μm. • Composite PTFE media saved over 50% energy consumption at 8 g/m2 loaded dust mass. Enormous energy has been consumed by cleanroom ventilation systems due to their characteristics of greater flowrate and round-clock operation. The novel PTFE HEPA filters/media have much lower initial resistance compared to traditional glass fiber HEPA media, but their life span energy consumption may be greater due to their larger resistance growth speed. According to resitance growth characteristics of PTFE media, composite PTFE media were developed in the current study to improve their energy consumption performance by replacing their windward material with efficient media. Three electret filter media and three glass fiber media of different filtration efficiencies were used for developing six composite PTFE media. Dust loading experiments using eligible polydisperse KCl aerosol were conducted for these composite media and their mass averaged resistances during dust loading compared. The effects of windward media efficiencies on the performance of composite PTFE media were also experimentally investigated. Results showed that the energy consumption performances of PTFE HEPA media were significantly improved after being composited. The PTFE medium composited with the E6 electret medium had 246% greater loaded dust mass at final resistance of 900 Pa and 59% lower energy consumption at loaded dust mass of 8 g/m 2 than the original PTFE HEPA medium.

Comparative Test on the Bond Damage of Steel and GFRP Bars Reinforcing Soft Rock Slopes

Soft rock slopes were anchored with traditional steel bars and new Glass Fibre Reinforced Polymer (GFRP) bars. The difference in the anchorage performance of the two kinds of anchorage elements in soft rock and expansive soil was studied by an in-situ test. The results show that cyclic load can aggravate the bond damage of the interface between grouting body and both kinds of bars used in soft rock. Compared with the number of cyclic loads applied, the previous maximum load is the main factor that influences the bond damage of the anchorage bar. Under constant loading, the interface bond behaviour of GFRP bar is better than the steel bar. Because of the small difference in elastic modulus between the GFRP bar and the grouting body, the interface bond around the GFRP bar can invoke more resistance of the grouting body efficiently which demonstrates its more effective anchorage performance than the steel bar under the same conditions. The anchorage structure of steel bar in soft rock can generate larger interfacial relative displacement with increasing load than the GFRP bar in the anchorage section, even though the elastic modulus of steel is much larger than GFRP. In the expansive soil, the anchorage structure deformations of steel and GFRP bars are almost the same because of the weaker bond at the interface of the grouting body and the surrounding soil than that of the bar interface. Under the ultimate loading of the anchorage structure in soft rock, the steel bar with 450 MPa which is less than its ultimate strength shows the failure of the bar body pulling-out, and the GFRP bar with 508 MPa which is larger than its ultimate strength shows the failure of the bar body by fracture. The steel bar anchorage structure in soft rock is destroyed at the interface around the grouting body. The results show that the GFRP bar performs more efficiently than the steel bar.

Numerical and experimental validation of SMArt thermography for the inspection of wind blade composite laminate

An innovative active thermography technique is proposed for the inspection of typical wind blade material. The proposed technique is based on the use of a multifunctional material obtained adding a grid of Shape Memory Alloy wires, which would serve also as a protection against lightning, to a traditional glass fibre composite panel. This technique, called SMArt thermography, which exploits the SMA wires as internal heat sources, has been compared to a traditional pulsed thermography in the case of a representative panel of unidirectional glass fibre and epoxy matrix with embedded SMA wires and artificial defects. The experimental results of the two techniques are reported and compared to the result of a numerical FEM transient model, in order to establish the reliability and the detectability limit of the proposed technique. The FEM model has been proven to be a useful tool for the definition of the multifunctional material at a design stage.

Damping assessment of new multifunctional epoxy resin for aerospace structures

The increasing demand for more advanced materials, particularly in the aerospace field, has led to the development of carbon-fiber-reinforced composite manufactured employing different kinds of nanoparticles. The reinforcement with Carbon Nanotubes (CNTs) allows the modulation of several characteristics of the composite, which becomes suitable for more extreme operating conditions. Furthermore, the incorporation of CNTs in polymeric matrices of composite materials allows them to be electrically conductive, and hence suitable for developing self-responsive/self-protective materials characterized by a combination of properties strongly requested for replacing the traditional composites. In addition, detection of specific electrical properties can be used to develop self health-monitor composites subjected to damages due to static and dynamic loads. For instance, damage detection through conductivity measurements offers many advantages when compared to traditional glass fiber optic sensors. In fact, because of their high cost, it is not possible to create a dense network of these fibers to inspect large parts of the composite and especially if the damage spreads in the material without crossing the fiber. Therefore, the use of carbon nanotubes may provide an effective solution to overcome the described limitation. As part of an intensive research activity aimed at studying the performance of innovative smart resins, in this article, the authors show the outcomes related to some of the dynamic properties of the developed resins. Relevant results related to the enhancement of dissipative phenomena have been found in formulation modified with elastomeric phase e CNTs.

Serial Casting for Early Onset Scoliosis: Comparison of Three Casting Materials

Purpose: Plaster of Paris (POP) is the historic gold standard material for derotational cast application in children with early onset scoliosis (EOS). At our institution, fiberglass has supplanted POP for spinal casting of EOS utilizing two different fiberglass techniques. The first method is done on a Risser-type traction table to facilitate rolling of the traditional fiberglass tape. The second method is done with manual traction on a standard flat-top table using a tubular fiberglass hybrid …