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The main objective of the research is developed toward adsorption electronic devices (Interface material) with the performance examined by the physical, mechanical, and thermal properties of the E‐glass fiber reinforced with the epoxy composite and particulate dispersed into the matrix in partial fulfillment of tiny amount of aluminum powder particles and MWCNT. Composite membranes with 15 wt.% E‐glass fiber and 2 wt.%, 4 wt.%, and 6 wt.% fine aluminum powder particle concentrations were partially filled with 0 wt.%, 0.5 wt.%, and 1.0 wt.% MWCNTs. Vacuum lay‐up technique is used to create the better adhesive hybrid composite, which is then assessed of the characteristics of the materials. The maximum thermal conductivity of EAEM2 (E‐Epoxy, A‐Aluminum particle, E‐E‐glass fiber, M‐MWCNT) is 0.3057 W/mK. The tensile, bending, and impact strengths of EAEM1 composites are higher than those of EAEM2 and EAEM3 (average values of EAEM1 composites: 86 MPa, 123.33 MPa, and 90.66 J/m2). However, the Shore‐D hardness of EAEM3 is 95.33. The test findings demonstrate a significant improvement in thermal properties with minimal marginal decrements in mechanical capabilities when carbon allotropes are increased. The composite system's morphology (EAEM3) demonstrates a clustered distribution of aluminum powder particles in the matrix. [ABSTRACT FROM AUTHOR]

Frontal polymerization (FP) is a self-sustaining reaction that relies on polymerization exothermicity and heat transfer. This study explores the inplane and in-depth FP mechanisms of continuous fiber-reinforced epoxy composites. First, the effects of initiator and diluent concentrations on the FP behaviors of neat epoxy resins were examined. It was found that the frontal velocity and frontal temperature of the neat resins increase with an increase of either the initiator concentration or the diluent content, depending on the polymerization enthalpy and curing kinetics. Then, the FP behaviors of continuous carbon fiber and glass fiber-reinforced epoxy woven composites were investigated. The results showed that the in-plane FP behavior of the composites was primarily controlled by the thermal conductivity and specific heat capacity of the continuous fibers, whereas the in-depth FP behavior mainly depended on the pores of the woven fabrics. Highlights • Frontal velocity and temperature of neat resins are controlled by the polymerization enthalpy and curing kinetics. • The in-plane FP behavior of continuous fiber reinforced composites is dependent on the thermal conductivity and specific heat capacity of the fibers. • The in-depth FP behavior of composite is determined by both the thermal conductivity of fibers and the pores of fabrics. [ABSTRACT FROM AUTHOR]

In this study, we compare the effect of various precursor‐based graphene oxide (GO) nanofillers on enhancing the mechanical performance of E‐glass fiber‐reinforced epoxy resin composites (EGFPs). GO derived from bituminous coal (BC‐GO) and graphite (Gr‐GO) were dispersed into an epoxy resin matrix. The resulting mixture was combined with E‐glass fiber mats using vacuum‐assisted resin infusion molding. Notable improvements (38.9% in flexural strength, 22.9% in tensile strength, and 21.6% in impact strength) were observed in BC‐GO‐reinforced EGFPs at 0.25 phr loading of BC‐GO. The improvements for Gr‐GO‐reinforced EGFPs were 28%, 9.3%, and 6.8%, respectively. XRD analysis of BC‐GO showed a diffraction peak at 2θ = 20.9°. Except for this peak, no other crystalline peaks were observed when BC‐GO was incorporated into EGFPs. FTIR spectra of both composite samples, with or without the nanofiller, were similar due to the spectral peaks overlap. TEM demonstrated the exfoliated morphology of BC‐GO in EGFPs. These findings underscore the potential of BC‐GO as a cost‐effective reinforcement for polymer nanocomposites across various industrial applications, including the development of lightweight and strong materials for aerospace and automotive industries, protective coatings, petroleum, and aerospace production systems. Highlights: BC‐GO demonstrates superior mechanical performance compared to Gr‐GO in EGFPs.0.25 phr BC‐GO improves 38.9% flexural, 22.9% tensile, and 21.6% impact strengths.Beyond 0.25 phr, BC‐GO and Gr‐GO showed a decline in mechanical enhancement.Role of particle size, loading & adhesion to matrix analyzed using XRD, FTIR, and DLS.Coal‐GO is an attractive alternative nanofiller for EGFPs. [ABSTRACT FROM AUTHOR]

Glass fibers (GFs) are frequently employed as reinforcement fibers for polymer resins such as epoxy and polyester. The mechanical behaviors of GFs polymer composites are nevertheless constrained by weak interfacial adhesion between polymer matrix and GFs. Herein, we invented a cross‐linking modified sizing agent using polyethyleneimine and bisphenol A epoxy emulsion, and studied the effect of cross‐linking extent on GF surface characteristics and GF/epoxy interfacial adhesion. The treatment of GFs with cross‐linking modified sizing agent facilitated the formation of interpenetrating polymer networks in composites for strengthening interface interaction. The results show that the modified GFs have a rough surface and improved interfacial adhesion with epoxy matrix. When sizing agents with cross‐linking extent of the 23.0%, the GF/epoxy composites show advanced interfacial shear strength (IFSS) and transverse fiber bundle tension (TFBT) strength. This work demonstrates that the cross‐linking extent of sizing agent could regulate interfacial adhesion, which is a facile and promising strategy in reinforcing glass fiber polymer composites. Highlights: Crosslink the sizing agent to enhance GF mechanical properties was reported.GF surface energy was enhanced and thickness of GF/epoxy interphase increased.IFSS and TFBT strength of the GF/resin composites increased by 23.65% and 30.54%, respectively. [ABSTRACT FROM AUTHOR]

Glass fiber‐reinforced polymer‐matrix (GFRP) composites are used to manufacture devices such as radomes, electrical insulators, and radar‐absorbing structures, many of which are used in applications with strict mechanical and dielectric property requirements. As such, designs and properties of GFRP composite materials should be regularly improved to guarantee their safe operation and meet their constantly evolving application requirements. In this study, glass fiber (GF) particles and epoxy resin 128 (EP‐128) were used to manufacture high‐performance EP/GF‐X composites with GF particle contents ranging from 5% to 40%. An investigation into their mechanical and dielectric properties revealed that EP/GF‐20 composite specimens presented the best mechanical performance with their bending strength and modulus reaching 159.68 MPa and 6521.92 MPa, respectively, and an average dielectric constant of 4.862 within the 10–105 Hz frequency range. A theoretical analysis of the EP/GF‐X composite specimens' dielectric constants using classic dielectric models based on the Lichtenecker, Bruggeman, Jaysundere‐Smith, and Maxwell‐Garnett rule‐of‐mixture equations indicated that the dielectric model based on the Bruggeman rule‐of‐mixture equation provided the dielectric constants closest to the measured values with a maximum deviation of less than −0.321% for EP/GF‐40 composites. This study provides a feasible strategy to control the mechanical and dielectric properties of GFRP composites. Highlights: Glass fiber (GF) particles and epoxy 128 (EP‐128) resin were used to manufacture high‐performance glass fiber‐reinforced epoxy (EP/GF‐X) composites.The composite manufacturing process was carefully controlled to ensure uniform distribution and orientation of GF particles in the EP‐128 resin.The mechanical and dielectric properties of the manufactured EP/GF‐X composites were effectively tailored by controlling the content and distribution of GF particles in the EP‐128 resin matrix.The dielectric constants of the EP/GF‐X composites were measured experimentally and predicted using various theoretical dielectric models.The Bruggeman model provided the dielectric constants of the EP/GF‐X composites closest to the measured values. [ABSTRACT FROM AUTHOR]

The effect of incorporation of micron sized aluminum trihydrate, multi‐walled carbon nanotubes, and graphene nano platelets into glass fiber reinforced epoxy matrix is investigated using dynamic mechanical analysis. The objective of the investigation was to develop polymer central core of high temperature low sag transmission conductor. The effect of individual and hybrid carbon fillers on the viscoelastic properties of the epoxy composites is investigated and discussed. The storage modulus of the glass reinforced epoxy increases by 20% at room temperature due to incorporation of carbon nanofillers. In glass transition region, the increase is higher between 40% and 60% and it varies up to 90% in the rubbery region. Key attributes of carbon filler addition are limited enhancement of storage modulus at room temperature, higher enhancement over glassy, glass transition, and rubbery regions. The carbon fillers extend the temperature range of the glassy region. The cross‐link density, filler efficiency, and degree of entanglement of fibers are estimated to understand the implications of the carbon fillers on the viscoelastic properties. The loss modulus peak of glass epoxy composite increases from 2800 to 3900 MPa with carbon fillers and the increase in glass transition temperature is 47°C. Incorporation of carbon fillers leads to increase of damping factor peak from 0.2 to 0.28. Cole–Cole plots have established the inherent heterogeneity of epoxy systems due to the presence of carbon fillers. Prediction models for storage modulus and damping factor have been proposed to highlight the influence of geometry and size of carbon filler. [ABSTRACT FROM AUTHOR]

To alleviate the environmental pollution caused by waste wind turbine blades and provide new ideas for recycling, the thermochemical characteristics of four basic components of composite materials commonly used in wind turbine blades were studied in this paper. Thermogravimetric experiments in different atmospheres and heating rates, and thermogravimetric‐infrared combined experiments were carried out. The results show that the reaction of epoxy resin and thermoplastic polyurethane was easy and deep in N2 and CO2. Except for glass fiber, the other three components showed different combustion characteristics in air. The maximum reaction rates and activation energy of resin‐based components in N2 increased with increasing heating rate. The pyrolysis products of the four basic components all contained CO2 and CO, and some aromatic substances could be generated during the thermal transformation of epoxy resin and thermoplastic polyurethane. It can be concluded that the thermal transformation properties of the basic components of the composite material of wind turbine blades can be used to treat the waste blades, making the resin as the matrix material undergo a thermal transformation reaction and recover the fiber. This is to effectively guarantee the green and sustainable development of wind power generation. [ABSTRACT FROM AUTHOR]

For commercial civil applications of laminated composite material, characterizations to forecast the interlaminar shear behavior and viscoelastic response across a wide temperature range are essential. In this study, the interlaminar shear strength (ILSS) of glass/epoxy (GE) composites dispersed with binary nanofillers nanosilica‐multilayer graphene (NS‐MLG) and nanosilica‐nanoclay (NS‐NC) was analyzed at an in‐situ testing temperature of 20, 70, and 110°C. Further, the viscoelastic property of the composites was studied using a dynamic mechanical thermal analyzer (DMTA) in the temperature range of 35–165°C. An increase in the ILSS value of around 9% and 10% was observed at room temperature for GE/MLG‐NS and GE/NC‐NS, respectively, compared to control GE composites. In contrast, the trend was seen to change at higher temperatures. There was a slight decrement in the storage modulus (E′) of GE/MLG‐NS and GE/NC‐NS composites in the glassy region compared to control GE composites. The mean Tg of the GE composite (control) was nearly 107.3°C when the E′ decline onset temperature was taken into account, but after the addition of MLG‐NS, it was 10.1°C below. The mean Tg of GE/NC‐NS was determined to be 106.3°C, and in the glass transition as well as rubbery regions, it was observed to compete with the E′ value of the control GE composites. Fractography was done using micrographs obtained from environmental scanning electron microscope (ESEM). Traces of polymeric material found at the fiber surface certified the improved interfacial adhesion between glass fiber and polymer in the matrix‐modified composite samples. [ABSTRACT FROM AUTHOR]

The development of innovative engineered epoxy composites aiming to manufacture cost‐efficient materials with reduced weight and enhanced physical properties remains as a current industrial challenge. In this work we report an original procedure for manufacturing glass‐fiber epoxy reinforced nanocomposites (GFECs) by employing electrospun fiber‐mats as a reinforcing phase. These fibers have been produced from polyacrylonitrile and multiwalled carbon nanotubes solutions. Optimal protocols are designed by combining Taguchi method with the morphological, structural and mechanical properties obtained by scanning electron microscopy, profilometry and tensile tests. It is demonstrated that GFECs fabricated using GF800 glass fiber show an improvement/enhancement of the mechanical properties with a fracture strain up to 500 MPa (around 20% higher than the non‐reinforced epoxy composite counterpart). It is also shown that GFECs fabricated using GF3M glass fiber exhibited a reduction of the roughness up to 56%, which corresponds with a roughness improvement from N8 to N7 following the guidelines provided by the ISO 1302. These results suggest that this type of nanocomposites would be suitable to be used in the aeronautics and automotive industries. [ABSTRACT FROM AUTHOR]

Glass fiber/polymer composites find extensive application in marine industry; however, the durability of theses marine structures has always been a matter of concern owing to their continuous exposure to harsh marine environment. The objective of this study is to consolidate and analyze the work that has been carried out so far, primarily focusing on the influence of the marine‐environment characteristics on water absorption and its subsequent impact on the mechanical properties of glass fiber reinforced composites. It is found that immersion time and operational temperature are the two prominent factors that influence the durability of these polymer composites. Moisture causes reversible changes such as plasticization and irreversible changes such as hydrolysis, cracking, and crazing which subsequently exerts a detrimental effect on the physical, chemical, and mechanical properties of epoxy resins. During the initial stage of water absorption, the moisture content increased rapidly with the immersion time, and then it increased slowly as the immersion time stretched until the moisture content in the specimen reached a saturation level. Prolong exposure in water not only led to a substantial deterioration in static mechanical properties; it also altered the mode of failure from a brittle matrix‐ductile fiber to ductile matrix‐brittle fiber. [ABSTRACT FROM AUTHOR]

The fabrication of carbon fiber‐reinforced polymer composites generates vast amounts of waste carbon fiber. In the present work, these waste carbon fibers were added in varying contents (0.1, 0.3, and 0.5 wt%) to glass fiber/epoxy (GE) composite as short carbon fibers (SCFs) to improve its ambient and elevated temperature mechanical performance. The flexural and tensile behavior of the SCF modified GE composites were assessed at 30, 50, 70, and 110°C. The most significant improvement in mechanical performance was achieved by adding only 0.1 wt% of SCF into GE composite across most of the temperatures. At elevated temperatures, all the SCF‐modified GE composites showed superior mechanical performance over the control GE composite. An important correlation between SCF content in GE composite and elevated temperature mechanical performance enhancement has been discussed. Differential scanning calorimetry was performed to understand the effect of SCF addition on GE composite's glass transition behavior. Fractography was conducted to study the various failure mechanisms at ambient and elevated temperatures. [ABSTRACT FROM AUTHOR]

The objective of the present work is to understand how the main constituents of sizing modify the interfacial strength, the mechanical properties of epoxy composites as well as their durability. In this study, two model interphases between E‐glass fibers and epoxy resin were designed and studied in terms of adhesion and mechanical strength from nano to macroscale. The first one is made from a reactive sizing of APTMS silane coupling agent and DGEBA pre‐polymer film‐former. The other one contains a non‐reactive MTES silane and neutralized DGEBA film‐former. The sizings were evidenced by SEM/AFM observations and XPS spectroscopy. The characterization of the prepared composites by AFM nano‐mechanic mode, micromechanical tests revealed the effect of the sizing chemistry on the interfacial properties between glass fibers and matrix. The interfacial strength is more important for the composites reinforced with APTMS‐DGEBA sized fibers than those prepared with MTES‐BGEA sized fibers. In each case, an interphase area of around 200 nm width is detected at fibers vicinity. In this area, the elastic modulus is more than 25% lower than the bulk matrix modulus. [ABSTRACT FROM AUTHOR]

This study investigates the influence of reduced graphene oxide (rGO) coated glass fabrics on the strain sensing and the mechanical characteristics of fiber‐reinforced composites. Graphene oxide was applied in two thicknesses (threefold and fivefold coatings) onto a fabric using a padder mangle machine followed by thermal reduction and infused with an epoxy to manufacture rGO‐enhanced composite. The tensile modulus and flexural strength of the rGO‐enhanced composites with threefold coating were improved by 27% and 6.2%, respectively, compared with the equivalent composite manufactured without rGO. The normalized resistance (ΔR/R0) of composites increased by 0.89% and 3.48% under a cyclic tensile force of 1000 and 4000 N. The magnitude of ΔR/R0 was stable within 30 cycles suggesting a consistent strain sensing performance with a gauge factor of 15.55. The electrical response of the rGO‐enhanced composite was evaluated using a new industrial standard for sensors, by assessing calibration curves. The composite showed low hysteresis and low electrical viscosity which make these materials suitable for industrial piezoresistive strain sensors. [ABSTRACT FROM AUTHOR]

In sandwich composites, interfacial bonding between face sheets and core has to be strengthened to prevent debonding. In this work, sandwich composites with polyurethane core and glass fiber reinforced epoxy face sheets were prepared by vacuum infusion process. Chopped fibers of glass, carbon, and kevlar with length 12 mm were introduced between core and face sheets during fabrication in order to improve face‐core bonding. The influence of chopped fibers is investigated by testing flexural, compressive, shear, and fracture toughness properties of prepared specimens according to ASTM standards. Sandwich specimens with chopped glass fibers exhibited, superior interfacial bonding between the face and the core and hence improved the mechanical properties of sandwich composite. The chopped glass fiber embedded sandwich composite has an increased flexural strength of 32.77% and compressive strength of 21.43% when compared with plain sandwich composite. In addition, the shear strength and fracture toughness behavior of specimens with chopped glass fibers are superior when compared to other chopped fibers incorporated in the interfacial region. The interfacial region between skin and core was investigated using scanning electron microscopy (SEM). Chopped glass fibers in the interfacial region showed better adhesion property along with the epoxy. [ABSTRACT FROM AUTHOR]

In order to use the glass fiber reinforced polyphenylene sulfide composites (GF/PPS) in high temperature environments, thermal aging performance of two kinds of commercial grade PPS composites, reinforced by 40% glass fiber, PPS‐G40 HM and 1140L4, in thermal aging temperature of 250°C was compared by tensile strength, oxidized layer, color, crystallization and melting behavior. The results showed that tensile strength of GF/PPS composites is significantly decreased with increasing of aging time below 200 h and the tensile strength of aged PPS‐G40 HM is higher than that of aged 1140L4. The thickness of dark color area is increased with increasing of aging time. The thickness of oxidized layer of 1140L4 is thinner than that of PPS‐G40 HM. However, the color of oxidized layer of PPS‐G40 HM is lighter than that of 1140L4. The recrystallization in thermal aging results in the formation of crystal with higher melting point and increased melting temperature of GF/PPS composites. It is found that addition of epoxy resin can increase the initial mechanical property and improve the thermal aging performance of GF/PPS composites. A novel modified GF/PPS composite with higher thermal aging properties was obtained. [ABSTRACT FROM AUTHOR]

The article discusses the fabrication, mechanical characterization, and heat resistance of nano ZnO‐TiO2‐filled glass fiber‐reinforced LY556 epoxy composites, with focus on the synergistic effect of ZnO and TiO2 nanofillers. The fabrication of the composite laminates is achieved by the addition of the nanofillers in different wt% ranging from 1 to 5 wt%. The composites are prepared using simple hand layup technique followed by curing under vacuum. The 3D atomic force microscopy scans indicated even distribution of the nanofillers up to 2 wt% loading. Severe agglomeration of the nanofillers is evident for 3 to 5 wt% loading. The surface roughness, microhardness, flexural strength, tensile strength, and impact strength of the composites indicate a relationship with dispersion, wt% loading, and the wettability of the nanofiller with the LY556. In general, it is found that the incorporation of hard nanofillers favored the improvement of impact strength to a greater extent compared to tensile and flexural strengths. Detailed analysis of the obtained mechanical property values favors an optimum 2 wt% incorporation of the selected nanofillers to obtain improvement in various strength values of the fabricated composites. The thermal stability of the fabricated composites improved through the incorporation of ceramic nanofillers. [ABSTRACT FROM AUTHOR]

Hybrid multiscale fiber reinforced epoxy composite laminates were developed and characterized from woven glass fiber mats reinforced with nonwoven PAN nanofibers (diameters of 200 nm) produced via electrospinning. An electrospinning setup was designed and developed to produce continuous E‐spun nonwoven nanofiber (NWNF) mats, which were then used as interlaminar reinforcements for producing multiscale hybrid composites. A detailed study for producing E‐spun nanomats considering both solution and operation parameters was undertaken discussed and optimum spinning parameters were obtained. These parameters were used to produce the E‐spun NWNF mats, which were inserted into the interlaminar region of glass fiber reinforced epoxy laminates. The impact absorption energy, tensile strength, and flexural strength of the hybrid multiscale composites were found to increase with an increase in E‐spun NWNF mat weight fraction. These properties were compared to those of a conventional glass fiber composite laminates prepared from the neat epoxy resin with 32% glass fiber volume fraction. The effectiveness of the strengthening/toughening strategy formulated in this study indicates that the feasibility of using the E‐spun NWNF mat reinforcements for improving the mechanical properties of structured high‐performance composites. In addition, the present study provides motivation for the long‐term development of high‐strength high toughness bulk structural nanocomposites for broader engineering applications. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, the gallic acid-based epoxy resin (GA-ER) and alkali-catalysed biphenyl-4,4′-diol formaldehyde resin (BPFR) are synthesized. Glass fibre-reinforced GA-ER/BPFR composites are prepared. Graphene oxide (GO) is used to improve the mechanical and thermal properties of GA-ER/BPFR composites. Dynamic mechanical properties and thermal, mechanical, and electrical properties of the composites with different GO content are characterized. The results demonstrate that GO can enhance the mechanical and thermal properties of the composites. The glass transition temperature, Tg, of the BPFR/GA-ER/GO composites is 20.7°C higher than the pure resin system, and the 5% weight loss temperature, Td5, is enhanced approximately 56.6°C. When the BPFR: GA-ER mass ratio is at 4 : 6 and GO content is 1.0-1.2 wt %, the tensile and impact strengths of composites are 60.97 MPa and 32.08 kJ/m2 higher than the pure resin composites, respectively. BPFR/GA-ER composites have better mechanical properties, and can replace common BPA epoxy resins in the fabrication of composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42637. [ABSTRACT FROM AUTHOR]

The article describes the synthesis and properties of bis(4-cyanato e,5-dimethylpheny)anisylmethane/epoxy/glass fiber composites to reduce the weight of components in space applications. The purpose was to develop a new substance that could replace the brittle properties of high-modulus graphite/epoxy composites in such applications. It shows how the composite laminates exhibited increased tensile strength and achieved weight loss through the incorporation of cyanate ester in the epoxy resin.