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Three‐dimensional multi‐axial warp knitted (3D MWK) reinforced composites are important components of advanced structural composites. The interfacial bonding between fiber and matrix is key to achieving high mechanical properties. In this work, graphene oxide (GO) and poly(oxypropylene) diamines (D400) were grafted on glass fiber (GF) multi‐axial warp knitted (MWK) fabrics to construct a "flexible‐rigid" structure. The surface morphologies of GF were characterized by SEM and EDS. Then, 3D MWK‐reinforced composites were prepared based on four kinds of modified fabrics using the VARTM method. The in‐plane compression properties were obtained at different high temperatures and their failure modes were analyzed. The strain–stress curves showed that the composites exhibited brittle fracture modes. D400 and GO‐modified multi‐scale composites exhibited outstanding compression properties. The strength of the related composited was improved by 55.78%, 76.78%, 52.19%, and 56.78% compared to that of desized composite at 30°C, 60°C, 120°C and 150°C, respectively. The damage to D400‐GO modified and D400 modified composites was the most serious, where shear fracture modes were obvious in addition to layer debonding features. This protocol provides a potential strategy to manufacture of D400 and GO‐modified hierarchical reinforced composites. Highlights: The modified 3D MWK glass fabrics based on poly(oxypropylene) diamines (D400) and graphene oxide (GO) were prepared.The compressive properties of 3D desized, D400‐, D400‐GO‐, and GO‐MWK fabrics reinforced epoxy composites were obtained and analyzed at different temperatures of 30°C, 60°C, 120°C, and 150°C.The failure mechanisms of 3D desized, D400‐, D400‐GO‐, and GO‐MWK fabrics reinforced epoxy composites at different temperatures were analyzed. [ABSTRACT FROM AUTHOR]

The present investigation targets the physical, mechanical, and thermal characteristics of glass fabric‐reinforced vinyl ester/polyester hybrid laminates filled with ferrous, nickel, and tungsten micro‐particles. The metal‐fillers‐glass fabric reinforced vinyl ester/polyester hybrid composites was produced by distributing 1 wt% ferrous, nickel, and tungsten with an ultrasonication probe‐assisted wet layup method. Polyester resin reinforced with glass fabrics and tungsten fillers (PRGT) presents improved mechanical characteristics compared with other hybrid laminates, with tensile, compression, and flexural strength values of 157.89 MPa, 163.74 MPa, and 167.29 MPa, respectively. The fractographic microstructure of tensile fracture PRGT laminates exhibits that glass fibers pull out, microcracks, and lower gaps, because of stronger filler‐fabric‐matrix adhesion when compared with other hybrid laminates. The artificial neural network modeling was conducted to choose the best composite among the various manufactured composites. Statistical analysis was observed from the one‐way ANOVA technique, substantiating that the physical, mechanical, and thermal characteristics of metal fillers‐reinforced hybrid composites were statistically significant. Highlights: Metal‐fillers‐glass fabric reinforced vinyl ester/polyester hybrid composites.Selection of the best composite from developed composites by ANN.Tungsten fillers are a useful material for reinforcement. [ABSTRACT FROM AUTHOR]

This research investigates the influence of kevlar and glass fiber reinforcements on the mechanical and thermal properties of epoxy/vinyl ester (hybrid resin) composite. The hybrid resin was synthesized by achieving an interpenetrating network between epoxy and vinyl ester. The composites were characterized using tensile, flexural, impact, and thermo‐gravimetric analysis (TGA). Scanning electron microscopy was employed to analyze surface morphology whereas Fourier‐Transformation Infrared Spectroscopy (FT‐IR) was used to investigate the possible interaction between the constituents of the composites. The findings have shown a notable improvement in the mechanical properties after the hybridization of the resin. For reference, the tensile strength of glass/hybrid resin and kevlar/hybrid resin composites were observed to increase by 8.33% and 23.65%, as compared to glass/epoxy and kevlar epoxy composites respectively, whereas, the bending strength of these composites was improved by 8.36% and 30.61%, respectively. TGA also showed an enhanced thermal stability of the hybrid resin‐based composites. Such improvements are noticed due to multi‐resin incorporation (the oxirane group of epoxy reacts with the hydroxyl group of vinyl ester), confirmed by the FTIR, TGA, and morphological analysis. This study signifies that the proposed hybrid composites are better in terms of strength and modulus relative to conventional metallic materials. Highlights: The paper presents the development of novel hybrid resin, reinforced with synthetic fibers.Hybrid resin is imparted positively and is highly favorable in improving the mechanical properties of composites.The tensile strength of novel composites is increased by 8.33% and 23.65% relative to their base specimens, and a similar trend is observed in flexural and impact analysis.Fractured analysis showed that composite laminates deteriorated more intensely due to cohesive matrix fracture; adhesion failure was not observed at all, as evidenced by the emergence of micro‐cracks in resin.Developed novel composites exhibited maximum thermal stability; residual char in glass/epoxy/vinyl‐ester composite attained 17.81% higher, whereas kevlar/epoxy/vinyl‐ester achieved 3.56% relative to glass/epoxy and kevlar/epoxy base samples. [ABSTRACT FROM AUTHOR]

This study focused on the wear behavior of unidirectional, thick GF epoxy composites produced using the autoclave method. The thermal aging process was applied for 250 and 500 cycles to understand the wear behavior of the material as it ages over time. To evaluate the wear behavior of the samples, wear tests were carried out under three different loads (10, 20, and 30 N) and three different sliding distances (150, 300, and 450 m). Taguchi‐based regression analysis was used to analyze the experimental results. The results obtained were evaluated using ANOVA tables and main and contour graphs. When the test results are examined, it is surprisingly observed that the wear resistance of the composite material increases positively with the aging effect. With thermally aging while the coefficient of friction value of composite samples increases from approximately 0.12 to 0.3, the wear volume decreases from approximately 4 to 1.3 mm3. Taguchi based regression analysis showed that the relationship between wear and thermal cycle sliding distance and load can be established by reducing the number of experiments in wear studies. Highlights: Thermal aging effect on wear properties of thick GFRP was determined.Minimum wear volume and COF values were determined by applying ANOVA.It was determined that a load increment has the most impact on wear volume.Worn surface images supported the reduction in the wear rates of the thick GFRP.Empirical regression models developed for the mathematical prediction. [ABSTRACT FROM AUTHOR]

Glass fiber‐reinforced resin matrix composites have good mechanical and impact resistance properties, while with particle co‐reinforcement, a synergistic effect can further improve their performance. In this paper, continuous glass fiber‐reinforced nylon 6 (GF/PA6) and continuous glass fiber (GF) with glass beads (GBs) co‐reinforced nylon 6 (GB–GF/PA6) were prepared to investigate the co‐reinforcement mechanism and the synergistic effect of particle and fiber. A quantitative parameter of the residual impact force divided by the critical force Pr/Pcr, as the damage degree of the low‐velocity impact, is defined to evaluate the impact resistance of the composite. The results indicate that the damage of GB–GF/PA6 was lower than that of GF/PA6, and the synergistic effect reaches the most obvious at the GB addition of 10 wt%. Scanning electron microscope (SEM) and x‐ray computed tomography (XCT) images disclose that GB impedes the type II crack spread in the matrix and fiber/matrix interface. With the type II cracks reducing, the materials' resistance to delamination can be significantly enhanced. For the composite structure, in which 10 wt% GB and 60 wt% GF are introduced, the flexural strength, shear strength, and pendulum impact strength were tested with the maximum values of 379.4 MPa, 53.1 MPa, and 219.0 J/m2, respectively. This composite structure design, presenting a continuous GF and GBs co‐reinforce effect, offers a manufacturing process that is easily scalable to achieve excellent characteristics. [ABSTRACT FROM AUTHOR]

Honeycomb composite with excellent mechanical–physical properties had attracted extensive attention. To achieve outstanding sound insulation while maximizing the high‐performance of honeycomb composite, this article reported a honeycomb composite structure filled with glass fiber (HFG) based on a paper‐making process and the corresponding sandwich structure. Pulping parameters, mechanical property, air permeability and sound insulation of HFG were analyzed. The results showed that the hanging index and settling height of glass fiber slurry were inversely proportional to the beating degree, which was beneficial for reducing the coefficient of variation (CV) of HFG with value of 4%–6%. The maximum improvement in tensile strength and bursting strength of HFG were 70% and 53%, respectively. In addition, sound transmission loss (STL) of HFG was proportional to cell size, density, filling amount and thickness of the honeycomb. Compared to HFG, sandwich structure consisting of HFG and glass fiber/hot melt fiber panels effectively improved STL, especially at low‐mid frequencies. It was also found that designing holes on the surface of sandwich structure could further improve STL in certain frequency bands. The structure offered a lightweight and high‐performance response for construction, transportation and infrastructure. Highlights: This article designs a new type of honeycomb filled glass fiber via paper‐making process, aiming to improve the comprehensive performance of honeycomb.By the design of embedded structure, the maximum improvement in tensile strength and bursting strength of honeycomb were 70% and 53%, respectively.By designing perforated, embedded and laminated structures, sound insulation has been improved, while reducing material quality. [ABSTRACT FROM AUTHOR]

Composites with excellent flame retardant and mechanical properties are in high demand in the aerospace and various industrial fields. Glass fiber (GF) reinforced polyimide (PI) composites (GFRPCs) were fabricated using a simple ball milling and hot pressing technique. The effect of GF content on the thermal stability, mechanical and flame retardant properties of composites has been systematically studied. The Rockwell hardness of GFRPCs increase with increasing GF content, while the compressive strength, impact strength and flexural strength initially show an increase followed by a decrease due to the excellent dispersibility of the fillers and the strong interfacial interaction between the one‐dimensional GF and PI matrix. Thermogravimetric analysis results show that the addition of GF with very low thermal conductivity and excellent temperature resistance can effectively improve the thermal stability of PI. Adding GF into PI can obviously improve the limiting oxygen index value. Moreover, as the GF content increased, the time to ignition of the composites prolonged while total heat release decreased. These findings suggest a viable solution for enhancing both the flame retardance and mechanical properties of PI‐based composites. Highlights: GFRPCs with high GF content fabricated via ball milling‐hot pressing method.Silane modified GF obviously improves the thermal stability of PI matrix.GFRPCs‐28 exhibits superior mechanical properties.An increases in time to ignition (TTI) and mass residual rate (MRR) of the GFRPCs was observed on adding GF. [ABSTRACT FROM AUTHOR]

The natural and synthetic fibers are combined in a single composite to achieve a balance between the desired strength and cost considerations. In this study, the vacuum resin transfer moulding process was used to prepare an epoxy‐based composite. The composite consisted of grewia optiva as the natural fiber and glass fiber as the synthetic fiber, both with a fixed weightage of 10 %. Dolomite was used as a filler with varying content (0 %, 5 %, 10 %, and 15 weight %). The physical, mechanical, erosion wear and morphological behavior of the epoxy‐based composite were investigated. The inclusion of dolomite filler significantly increased the composite hardness and impact strength but reduced its tensile and flexural strength. At a dolomite filler content of 10 weight %, the erosive wear was reduced, while it increased at higher dolomite filler contents. The composite was examined using the L16 array, and the minimum wear rate was observed at an impingement angle of 30°, a velocity of 10 m/s, and an erodent size of 150 μm. Morphological studies were conducted to explore the possible mechanism for the variation in erosive wear at different dolomite contents in the hybrid composites. [ABSTRACT FROM AUTHOR]

Silica, a principal component of waste glass powder (GP) reacts with calcium hydroxide to form the hydration products, and the process is affected by the fineness of GP and the percentage of cement replaced. This study investigates the structural behavior of concrete incorporating GP in reinforced concrete members by 0%–25% (by weight) replacement of cement with GP along with 0%–0.45% addition of glass fibers (GFs). The compressive and tensile strengths, strength activity index (SAI), and failure mode of treated concrete mixtures have revealed the optimum values as 15% replacement of cement with GP with 0.3% of GF. In the second stage of experiment, reinforced concrete beams were cast at various percentages of GP and GF to investigate the load–deflection response. It was observed that the beam specimen treated with GP exhibited considerably less mid‐span deflection (14.8 mm) at failure as compared to the control beam (with no GP and GF) which failed at 29.4 mm. The beam specimen treated with GP only showed significant degradation in stiffness after the peak load due to the fact that a part of GP remains unreacted and acts as a filler. Moreover, the beam specimen cast at optimum percentages of GP (15%) and GF (0.3%) showed large mid‐span deflection and higher failure load as compared to the control beam. These results suggest that the partial replacement of cement with GP should be accompanied by the addition of fibers to avoid unwanted brittle responses of GP concrete, with the additional advantage of reducing the non‐biodegradable waste. [ABSTRACT FROM AUTHOR]

In this work, the effect of the kind of reinforcement on the sliding wear performance of a polyester matrix composite reinforced with glass fiber and pineapple leaf fiber is investigated. The purpose of this study is to ascertain the effects of the type of reinforcement on the sliding wear performance of a polyester matrix composite reinforced with glass fiber and pineapple leaf fiber. By using hot press molding and the 30% weight fraction of fiber reinforcement, polyester composites with four distinct compositions—PPP, GGG, PGP, and GPG—have been created. These composites' dry sliding wear experiment is carried out using a Pin on Disc wear testing device. The following parameters are used in experiments: a track radius of 50 mm, a sliding distance (SD) of 500 m, an applied load of 50, 70, or 90 N, and a sliding velocity of 3.14, 4.71, or 6.28 m s−1. For dedicated (PPP, GGG) and hybrid (PGP, GPG) polyester composites, the effects of load, sliding velocity (SV), and wear rate (WR) are studied. At 50 N and 3.14 m s−1 the COF for PPP and GGG dedicated composites is 0.68 and 0.70, respectively, whereas for PGP and GPG hybrid composites, it is 0.41 and 0.64. The PGP/GPG hybrid composites have a minimal wear rate of 3.34e‐8 m3 s−1 and are 80% more effective than dedicated composites. Utilizing the Analysis of Variance (ANOVA) and Taguchi L9 orthogonal array, regression models are created to optimize the influence of various parameters, such as load, sliding velocity, and composition. Results of confirmation tests show excellent agreement with predictions generated using the developed mathematical model. [ABSTRACT FROM AUTHOR]

As an important surface modifier, conventional silane coupling agents generally emit volatile organic compounds (VOCs) like methanol or ethanol during the modification of glass fiber. To avoid VOCs emission, a phenol/amine co‐deposition of tannic acid (TA) with polyethyleneimine (PEI) was used to modify glass fiber (TP‐GF) based on mussel‐inspired surface chemistry. The reinforcement effect of TP‐GF on polyamide 6 (PA6) matrix was investigated, and the corresponding results were compared with those of γ‐aminopropyltriethoxysilane (KH550) modified glass fiber (KH550‐GF)/PA6 composites. The results showed that the interfacial adhesion between TP‐GF and PA6 matrix was superior to that between KH550‐GF and PA6 matrix, and thus TP‐GF/PA6 composites manifested more excellent mechanical properties than KH550‐GF/PA6 composites. Among these composites, TP‐GF (1.05 wt% of coating amount)/PA6 composites exhibited the optimal mechanical properties (tensile strength: 151.3 MPa, notched impact strength: 13.8 kJ m−2) compared with KH550‐GF (1.33 wt% of coating amount)/PA6 composites (tensile strength: 144.8 MPa, notched impact strength: 9.5 kJ m−2). In particular, the notched impact strength was significantly increased by 45%. Notably, there was no VOCs generation during the preparation of TP‐GF, indicating that TP‐GF could be used as an environmentally friendly glass fiber for the fabrication of high‐performance PA6 composites. [ABSTRACT FROM AUTHOR]

To facilitate the application of carbon black filled glass fiber reinforced poly‐ether‐ether‐ketone (CB‐GF/PEEK) prepreg in laser assisted tape winding (LATW), a finite element method is used to analyze the optical‐thermal characteristics of the following three prepregs with distinct laser absorption properties: (i) 0.5%CB (incomplete absorption), (ii) 2.74%CB (complete, single‐layer absorption), (iii) 4%CB (complete, near‐surface absorption). Thus, the energy distribution, temperature distribution and thermal accumulation are revealed, and the heating strategy is customized according to the laser absorption characteristics of each prerpeg. Then the feasibility of CB filled GF/PEEK prepreg in LATW is verified by manufacturing and testing NOL rings. Finally, the nip‐point irradiation scheme is optimized. The simulation results reveal a significant difference between the optical‐thermal characteristics of the 0.5%CB and those of the other two prerpegs. Benefited from the energy leakage, the 0.5%CB facilitated twice melting by thermal accumulation, along with a higher nip‐point temperature. Meanwhile, the mechanical performance tests of the NOL rings indicate a similar tensile strength of ~1300 MPa for the 0.5%CB and 4%CB, while the interlaminar strength of the 0.5%CB is slightly higher than that of the 4%CB. The latter result may be due to the higher nip‐point temperature of the 0.5%CB, which promotes resin diffusion and enhances the bonding strength. Finally, an optimized heating strategy with short laser length, vertical irradiation of the nip‐point is proposed, and is shown to reduce the ineffective thermal accumulation and ensured the suitability of Tape and Laminate temperature. [ABSTRACT FROM AUTHOR]

Aiming at the use of glass fiber reinforced poly‐ether‐ether‐ketone (GF/PEEK) with low laser absorbance in laser assisted tape winding/placement (LATW/LATP), a method for dyeing GF/PEEK prepreg with nanoparticle fillers (NFs) is presented. First, the effects of carbon black (CB) and graphite (G) NFs on composites laser absorbance and reflection pattern were quantified, and the complex refractive index model was derived. Next, the effects of NFs on composites transverse thermal conductivity were tested, and the accuracy of four thermal conductivity prediction models were compared. Finally, the effects of NFs on composites interlayer performance were studied. The optical test results showed that NFs could improve laser absorbance while not changing reflection pattern, and the increase rate of absorbance for CB was higher than for G. As calculated by complex refractive index model, GF/PEEK with 1‐layer thickness could achieve complete laser absorption by addition of either 2.74%CB or 3.78%G. The thermal conductivity test results showed that NFs could improve composites transverse thermal conductivity. The increase rate of thermal conductivity for G was higher than for CB. Among the four prediction model, the Lewis‐Nielsen model had correct prediction regularity and was within 10% predict deviation. Based on this model, the transverse thermal conductivity of GF/PEEK/2.74%CB was 0.557 W/m K, and of GF/PEEK/3.78%G was 0.592 W/m K. The mechanical test results showed that the CB loading ≤4% had little effect on interlayer performance, while the G decreased interlayer performance. Consequently, adding CB at a low loading is a better way to realize GF/PEEK application in LATW/LATP. [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]

Reinforcing the novolac matrix with glass fiber (GF) and graphite (Gr) was a promising method for producing high‐performance friction composites. In this context, the morphology of the matrix and additive particles used in the production of friction composites, microstructures, wear surfaces, and wear debris of friction composites were examined by scanning electron microscopy‐energy dispersive spectroscopy, while the crystal phases of the materials were scanned by X‐ray diffraction. Density measurements (Archimed's method), hardness, tensile behaviors, and thermal analyses (thermogravimetric analysis and differential scanning calorimetry) of friction composites were performed. The variations in coefficient of friction (COF) and temperature with the change in sliding time were observed in detail at different additive ratios. The tribological behaviors of these composites were tested using a computer supported block‐on ring machine at sliding speeds of 200, 250, 300, and 350 rpm, applied loads of 50, 100, 150, and 200 N and constant time of 1800 s under dry conditions. Results indicated that with increase in the GF and Gr content, the stability of the (COF) became more stable and effectively reduced the specific wear rate. In addition, the wear resistance increased in parallel with the increase in normal loads and sliding speeds for all conditions. [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]

Polyamide (PA) is the mostwidely used type of semi‐crystalline polymer among engineering plastics, with its low density and high mechanical properties. But the high moisture absorption of PA6 limits its use in some areas. Blending and the addition of reinforcement can decrease the moisture absorption value of PA6. In this research, the PA6/PA610 blends and glass fiber (GF) reinforced PA6/PA610 composites were fabricated, and the features of these blends‐composites were examined. The blends and composites were produced by using extrusion and injection molding methods and characterized by water absorption (WA) test, tensile test, scanning electron microscopy (SEM), dynamic mechanical analysis (DMA), thermogravimetric analysis, and differential scanning calorimetry (DSC). The loading rates of GF were used as 10–20‐ 30–40 wt%. According to the tensile test consequences, the highest increase in the tensile strength for the composites was observed at 30% GF ratio. DMA results demonstrated an increase in loss modulus and storage with the increasing fiber amount. It is observed that the WA value of neat PA6 was diminished by blending with PA610 and adding an increasing amount of GF. [ABSTRACT FROM AUTHOR]

Due to environmental issues and high cost of synthetic fibers, natural or cellulosic fibers have emerged as a promising reinforcement for polymer composites. The hybridization of natural fiber with synthetic fiber is a useful technique to improve the mechanical properties instead of using the natural fibers alone. This research aims to evaluate the influence of glass fiber hybridization on the mechanical properties of continuous, unidirectional, alkali (NaOH)‐treated kenaf‐epoxy composites. At first, the effect of treatment of various concentrations (3, 5, 7, and 9% w/v) of NaOH on the structure of single kenaf fiber was characterized using XRD, SEM, FTIR, and tensile testing. At the optimum 5% alkali concentration the tensile strength, modulus, and %elongation of the kenaf fibers were enhanced by 81%, 114%, and 42%, respectively. The effect of hybridization of 5% NaOH treated kenaf along with glass fiber on the improvement in tensile, flexural, and impact properties for hand laid kenaf‐glass‐epoxy hybrid composite laminates was established. The overall matrix to fiber weight ratio of five different layup sequence laminates was maintained constant at 70:30. It can be concluded from the obtained results that the 15% glass and 15% kenaf fiber hybridized composites exhibited the maximum increment in tensile strength and modulus (68.5% and 19.5%, respectively) in comparison to the unhybridized composites. Further, the flexural strength and modulus were also improved by 21% and 67%, respectively, and the impact strength by 153%. The SEM fractography proved that alkali treatment of fibers improved the fiber‐matrix interfacial bonding whereas fiber breakage, fiber pull‐out and debonding were established as the main fracture mechanisms of hybrid composites. The findings of the present investigation on kenaf‐glass hybrid composites corroborate that they are suitable for secondary structural applications in construction and automobile sectors. [ABSTRACT FROM AUTHOR]

Glass fiber (GF) reinforced nylon56 composites (nylon56/GF) were prepared by melting and blending through twin‐screw extruder with continuous fiber feeding. The structure and properties of the composites were characterized by electron density tester, polarizing microscope, scanning electron microscope, electro‐mechanical universal testing machine and thermal analyzer. The results showed that the density of the prepared composites is less than 1.37 g/cm3. There is strong interface adhesion between glass fiber and nylon56 matrix in the composite system, and the glass fiber length in the system is 0.47–0.61 mm. With the increase in the content of high‐performance glass fiber, the mechanical properties of the composite are significantly improved. When four bundles of GF are added, the properties of the nylon56/GF composite are the best. The tensile strength of nylon56/GF composite reaches 160 MPa, 86.9% higher than that of nylon56. The bending strength is 180 MPa and increases by 98.7% more than that of nylon56. The flexural modulus is 7100 MPa and rises by 125.6% compared with nylon56, and the impact strength is 11 kJ/mm2, which is 307.4% higher than that of nylon56. The nylon56/GF composite has a low density and excellent performance and can be widely used in locomotive and wind power. [ABSTRACT FROM AUTHOR]

Steel fiber is the most common metal fiber used due to its cost‐effectiveness, high performance, and availability despite its heavyweight. This study is an attempt to evaluate the mechanical properties of steel/glass fiber and steel/basalt fiber‐reinforced epoxy composites. The symmetric hybrid laminates were produced by replacing the innermost 1, 2, 3, and 4 layers of steel fiber (200 mesh size) with basalt and glass fiber layers. The specimens were subjected to tensile, flexural, and Charpy impact tests in accordance with relevant ASTM standards. Moreover, fracture surfaces were analyzed, and the micrographs were obtained using a scanning electron microscope. The results showed that a high improvement in tensile strength was achieved with BS1–E (1 layer steel mesh–8 layers basalt) and GS1–E (1 layer steel mesh–8 layers glass) hybrid composites, with an increase of 528% and 233%, respectively, compared to steel fiber reinforced epoxy composites. Similarly, BS1–E and GS1–E hybrid composites showed the highest flexural strength increase of 82.2% and 66.8%, respectively, compared to steel fiber reinforced epoxy composites. Consequently, the potential to hybridize steel fiber with glass fiber and basalt fiber could create new materials with unique physical structures and synergistic effects on mechanical properties. [ABSTRACT FROM AUTHOR]

Nowadays, reinforcement of fiber is necessary for concrete to enhance its quality with mechanical characteristics. The main objective of this work is to determine the mechanical properties of bamboo and glass fiber reinforced concrete. In concrete, E‐glass and bamboo fibers are mixed with three different proportions such as 25:75, 50:50, and 75:25. Cubical‐, beam‐, and cylindrical‐shaped concrete structures are developed for mechanical testing. After the curing period, the cubical structures are utilized for compressive strength testing, the cylindrical specimen for split tensile testing, and the beam‐shaped specimen for flexural strength testing. From the outcomes, 1% fiber substance (glass and bamboo fiber proportions of 75:25) provides better split tensile strength 4.13 N/mm2, compressive strength 42.08 N/mm2, and flexural strength 7.7 N/mm2. The comparative analysis of the proposed concrete composition with the conventional concrete mixture is also carried out. The experimental results are validated using support vector regression, and such predicted outcomes are closer to the experimented values. Furthermore, the ETABS platform is utilized for validating the proposed hybrid fiber reinforced concrete (HFRC) with single reinforcement‐like glass particles. In which, the testing properties like bending moment, shear force, and axial force are favorable for the HFRC. [ABSTRACT FROM AUTHOR]

Using star‐branched polyamide 6 (SPA6) with hexafunctional cyclotriphosphazene core as a matrix resin and glass fiber (GF) as a reinforcing material, star‐branched polyamide 6/glass fiber (SPA6/GF) composites with different GF content were prepared by melt‐compounding method. The star‐branched structure of SPA6 and GF content have great effects on the properties of SPA6/GF composites. Compared with linear polyamide 6 (LPA6), SPA6 with star‐branched structure has low viscosity, high melt flowability and good impregnation and adhesion to GF, which endow SPA6/GF composites outstanding processability, good surface qualities and excellent mechanical properties even when the content of GF reaches 60 wt%. The use of SPA6 resin with star‐branched structure fundamentally solves the industry problem of traditional LPA6 resin in high‐filled modification. Such high‐performance SPA6/GF composites will provide great promise for large‐scale applications. [ABSTRACT FROM AUTHOR]

In the selection of materials for deep‐sea equipment, light weight and high strength are the most important criteria or requirements. In this paper, hollow glass microspheres (HGMS), expanded polystyrene (EPS), epoxy resin (EP) and curing agent were mixed to prepare hollow glass microspheres reinforced epoxy foam balls (HGMS‐EHS) by the rolling ball method. Glass fiber (GF) reinforced epoxy syntactic foam (GF‐ESF) was prepared by mixing HGMS‐EHS, HGMS, EP, GF, and curing agent using compression moulding method. By analyzing the mechanical properties and microscopic morphology of GF‐ESF, the results show that the addition of GF does enhance the compressive strength of epoxy syntactic foam. GF‐ESF has a density of 496 kg/m3, and its compressive strength is 30.48 MPa. By increasing the number of layers of HGMS‐EHS, the diameter of EPS, the density of HGMS and reducing the stacking volume of HGMS‐EHS, the density of ESF increased significantly thus subsequently increase the compressive strength. Therefore, the compressive strength and density should be considered comprehensively and find the best balance point in the process of preparing ESF. This paper could provide some suggestions for the preparation of deep‐sea epoxy composites. [ABSTRACT FROM AUTHOR]

Hybrid composites have become the focal point of research communities due to the balance in mechanical and ecological properties of such materials. Hybridization is an efficient technique to strengthen and enhance the performance of composite materials. In this research study, hybrid composites were prepared by embedding pineapple leaf and glass fibers in polypropylene polymers via the hot press molding compression technique. Mechanical tests were carried out to determine the tensile, flexural and Charpy impact properties of pineapple leaf/glass fiber‐reinforced hybrid composite laminates. Additionally, water absorption test was also conducted to investigate the influence of hybridization on the moisture uptake of hybrid composites. In accordance with the findings obtained, the hybridization of pineapple leaf with glass fibers was found to improve the mechanical properties and moisture uptake sensitivity of the composite laminates. The [G/P/G] composite laminates are especially promising, having comparable mechanical strengths to those of non‐hybrid [G/G/G] composite laminates. Meanwhile, the water absorption and diffusion coefficient of [G/P/G] composite laminates were 66.64% and 40.71% lower than non‐hybrid [P/P/P] composite laminates. Based on the findings obtained, it is anticipated that the hybridization of pineapple leaf and glass fibers endows the composite laminates with lightweight characteristic, remarkable mechanical properties and low moisture uptake sensitivity while improving the environmental friendliness of the materials. Therefore, hybrid composites have indeed attested a very high potential to be used in transportation sectors. [ABSTRACT FROM AUTHOR]

In this study, the effect of alkyl ketene dimer (AKD) on the mechanical and physical properties of natural fiber (NF) and glass fiber (GF) reinforced poly(lactic acid) (PLA) composites were investigated in detail. The hybrid PLA composites were manufactured by extrusion method followed by hot press molding. AKD was used to improve the hydrophobicity of hybrid PLA composites and compatibility of NF and PLA in the polymer matrix. The tensile and flexural tests, thickness swelling, water absorption, and contact angle measurements were accomplished for determining the performance of the hybrid PLA composites. The surface morphology of the hybrid PLA composites was also performed by scanning electron microscopy. The incorporation of AKD and NF into PLA matrix improved the mechanical strengths by 40% and above compared to those of samples without AKD. But, tensile and flexural moduli decreased as 7% and 14% of the samples with NF and AKD, respectively. Contact angle was higher for the hybrid PLA composites with AKD compared with the composites without AKD. However, the results revealed that in the presence of GF, AKD had no significant effect on overall properties of the hybrid PLA composites. In the light of the findings, AKD may have a potential usage as coupling agent in the NF filled PLA composites. [ABSTRACT FROM AUTHOR]

Background/aims: Despite the use of conventional mouthguards, preventable sports-related dental injuries continue to occur. The authors have developed a two-layered ethylene polyvinyl acetate (EVA) mouthguard with a hard polyethylene terephthalate (PET) insert and a buffer space (H&SMG). However, adapting the PET onto the EVA layer requires skill. A light-cured Splint Resin (SRLC) and a glass fiber net (NET) reinforcement appear to resolve this issue. The aim of this study was to investigate whether SRLC with NET could replace PET and find a more practical application for NET.Materials and Methods: A pendulum impact testing machine and a dental model with strain gages were used. Six types of mouthguards were made: one with two laminated EVA blanks (LAM-MG), a three-layer type with a PET insert and an intermediate space (PET-H&SMG), a H&SMG with SRLC insert (LC-H&SMG), and three other types with differential NET-SRLC reinforcement; NET on the outer surface of SRLC, NET on the inner surface of SRLC, and NET on both the outer and inner surfaces. Five mouthguards of each type were fabricated and tested ten times with impact distances of 15 and 30 cm. Forty more impacts were applied to all H&SMGs to confirm the durability of the hard inner layer.Results: All H&SMGs showed significant strain reduction compared to the LAM-MG. PET-H&SMG and the four types of LC-H&SMG exhibited an equally slight strain (approximately 95% shock absorbing ability) in all conditions. During the test against the smaller impact, all H&SMGs showed no cracks. When tested against the stronger impact, only the LC-H&SMG with the reinforced inner surface, the double NET-reinforced LC-H&SMG, and the PET-H&SMG remained intact.Conclusion: The NET-reinforced SRLC can replace PET as an intermediate mouthguard material. The NET application, at least on the internal surface, is indispensable for the LC-H&SMG reinforcement. [ABSTRACT FROM AUTHOR]

Fiber reinforced materials have been widely used in the different fields in terms of their excellent properties. In this work, glass fiber reinforced poplar scrimber was in focus, and special attention was given to its dimensional stability with respective of different layers (0, 1, 2, 3) and mass fraction (1.5 wt.%, 3.0 wt.%, 4.5 wt.%, 6.0 wt.%, 7.5 wt.%) of glass fiber mesh. The experimental results showed that the glass fiber reinforced poplar scrimber with 2 layers and 6.0 % mass fraction of glass fiber mesh has the greatest dimensional stability and energy efficiency ratio. It is proposed to be adopted in the industrial processing of glass fiber reinforced poplar scrimber to improve its application and production benefit. [ABSTRACT FROM AUTHOR]

This research article presents the comparative investigation of physical, mechanical, and abrasive wear behavior of chopped glass and basalt fiber‐reinforced epoxy composites. The composites were fabricated by hand lay‐up technique. The fiber (glass and basalt) was varied in the range of 10 to 40 wt.% in the composite at an interval of 10 wt.% to find out the physical (density and void content), mechanical (tensile strength, flexural strength, and impact strength), and steady state abrasive wear rate, respectively. The Taguchi's design of experiment method was used for designing of experimental runs having input controlling variables like sliding distance, normal load, fiber content, and abrasive size. This study clearly demonstrated that with increase the fiber content, the density and void content of both fiber (glass and basalt) reinforced composite were increased. The basalt fiber‐reinforced composites show lesser voids than glass fiber‐reinforced composites. The tensile strength, flexural strength, and impact strength of both composites increased with increase the fiber content whereas glass fiber‐reinforced composites show slightly lower tensile strength, flexural strength, and impact strength than basalt fiber‐reinforced composites. However, as far as basalt fiber‐reinforced composites show better wear resistance than glass fiber‐reinforced composites. [ABSTRACT FROM AUTHOR]

Hexaphenoxycyclotriphosphazene (HPCTP), modified with phenoxy groups based on hexachlorocyclotriphosphazene (HCCP), has been proved that have excellent thermal stability. In this article, HPCTP and glass fiber (GF) were added into the rigid polyurethane foam (RPUF) to improve the flame‐retardant and mechanical properties of RPUF. The mechanical properties of composite were measured by compressive strength test. The micrographs were observed by scanning electron microscopy. Furthermore, the flame‐retardant and thermal properties were investigated by limiting oxygen index, cone calorimeter test, and thermogravimetric analysis. The results showed that the addition of HPCTP and GF would improve the mechanical and flame‐retardant properties of RPUF. [ABSTRACT FROM AUTHOR]

The effects of γ‐radiation on properties of three types of commercial alkaline earth aluminosilicate glasses (NJE, NJ1, NJ2) were investigated at 5M Gy dosage, using samples of bulk glass, glass fiber, and fiber reinforced laminate epoxy composite. The radiation‐induced defect generation and structural modifications in the bulk glasses were characterized by UV‐VIS‐NIR, FTIR absorption spectroscopy, respectively. Strong radiation resistance was found in NJ2 composed of high content of glass former such as Si and Al, together with variable Fe and Ce oxide. Mechanical properties of the fiber woven fabric taps and reinforced laminate composites were investigated before and after the irradiation. While the tap samples showed minor property degradations after the irradiation, all composite samples degraded by greater than 19% in tensile strength and greater than 55% in interlaminate shear strength (ILSS) at 5M Gy dose level. Deterioration of the composite mechanical properties is primarily attributed to the radiation damage to the epoxy resin and in turn, the failure mode of the irradiated composite samples is dominated by delamination at the interfaces between the fiber glass tapes and the resin under the applied tensile load or shear as compared with the failure mode of fiber breakages for their counterparts without γ‐irradiation. [ABSTRACT FROM AUTHOR]

This study aims to investigate the thermal, mechanical, and flammability properties of glass fiber (GF) reinforced PLA/PC composites. PLA/PC (50:50) blend was compounded and used as the control sample. Loading levels of GF were altered as 5, 10, 15, and 30 wt%. All composites were produced in a microcompounder and subsequently molded by injection molding. The properties of the composites were investigated by limiting oxygen index (LOI), tensile test, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscope, and cone calorimetry test. The maximum tensile strength value was observed for 30 wt% GF reinforced composite as 110.18 MPa. Similar initial degradation temperatures were obtained for the composites compared to the PLA. The maximum LOI value was determined as 23.1 for 30 wt% GF reinforced PLA/PC among the produced composites. Besides, it is observed that the addition of GF significantly decreased the total heat release rate. [ABSTRACT FROM AUTHOR]

Due to the widely tunable band gap and broadband excitation, CdS quantum dots (QDs) show great promise for yellow‐light luminescence center in white‐light‐emitting devices. The light intensity of the CdS QD‐doped glass was enhanced by doping the Tm3+ ions due to the higher absorption rate. The influence of Tm3+ ions on the surface structure of CdS QDs was enormous according to the first‐principles calculations. Doping Tm3+ ions change the surface state of CdS QDs, which will fix the QDs emission peaks and enhance the luminescence of CdS QDs at a lower heat‐treatment temperature. White‐light emission was obtained by tuning the relative concentration between Tm3+/CdS QDs. However, there is a fundamental challenge to fabricate QD‐doped glass fibers by rod‐in‐tube method since uncontrollable QDs crystallization is hard to avoid. Herein, a white‐light‐emitting borosilicate glass fiber was fabricated by the "melt‐in‐tube" method using a special designed Tm3+/CdS QDs co‐doped borosilicate glass with low‐melting temperature as fiber core. After heat treatment, ideal white‐light emission was observed from the fiber under excitation at single wavelength (359 nm). This finding indicates that Tm3+/CdS QDs co‐doped glass fiber with white‐light‐emitting devices has potential application as gain medium of white‐light‐emitting sources and fiber lasers. [ABSTRACT FROM AUTHOR]

Diffusion of water into Zr‐containing silica fiberglass materials was studied at room temperature by infrared spectroscopy. Several types of experiments were performed: (a) rehydration with H2O of fiberglass materials previously calcined in air at 450°C and under vacuum at 180°C; (b) isotopic experiments for uncalcined fiberglass materials using D2O with and without the presence of sodium. Water diffusion coefficients were determined in each case. It was suggested that the transfer of the protons and water molecules occurred by different mechanisms: the protons diffused through the hydroxyl groups via the relay mechanism like in liquid water, whereas water diffused more slowly in the form of molecular water. [ABSTRACT FROM AUTHOR]

In this work, a nanocomposite based on conductive polyaniline (PANI) was polymerized, via reverse microemulsion polymerization, in the presence of phosphoric acid and dodecylbenzenesulfonic acid. Applied simultaneously, these acids act as dopants, increasing the solubility of PANI in organic solvents. They further improve the corrosion protection performance of PANI by forming phosphate‐metal complex on metal surface. Zinc oxide nanoparticles were added to the PANI mixture before introducing ammonium persulfate. The final product of polymerization was added to an epoxy resin which served as the matrix for the coating. In order to improve coating elasticity, which can enhance coating resistance against impacts, E‐glass fiber (GF) was added to the coating formulation. It was observed that, with an optimized w/w%, the PANI/zinc oxide/GF composite improved the coating characteristics. Coatings were further subjected to stress‐strain and DC polarization tests, and their cross‐sections were investigated at break point by means of SEM. DC polarization plots revealed that the addition of zinc oxide can also shift the corrosion potential of steel toward positive potentials. [ABSTRACT FROM AUTHOR]

Because glass fiber reinforced composites are in industrial demand, chemistry and topography of the glass fiber sizing are of interest. Silane-PVA/PVAc (polyvinyl alcohol/polyvinyl acetate) complex film on the glass fiber surface is studied during thermal curing and water re-exposure by using atomic force microscopy. The complex film consists of silane with the honeycomb structure film and PVA/PVAc with the hexagonal close pack structure of ellipsoidal shaped microspheres (270 × 620 nm). The thermal curing at 100 °C is leading to the evaporation of water contained in the microspheres. Because of water evaporation, the average roughness value of 1-min thermal curing decreases from initial 7.3 to only 2.7 nm. Such a collapse of microsphere is followed by an intermixing between silane film and PVA/PVAc microspheres leading to a change of silane honeycomb structure along with silane tips. The average value of the silane honeycomb structure wall width decreases from 144 nm to 54 nm, for curing times of 15 and 30 min, respectively. A re-exposure to an aqueous environment after 100 °C curing leads to almost completely restored microspheres regarding shape and size. The average complex film thickness increases from 180 nm for thermal curing for 30 min to 225 nm for water re-exposed film. Interestingly, the pits in the microsphere structure are observed presumably because of the tips from intermixing. The thermal curing at 200 °C enhances the intermixing, and after 15 min, an intramixing is suggested to occur between PVAc core and PVA shell of the microsphere. The water re-exposure after 15 min of 200 °C curing leads to a re-containing of water but without restored microsphere structure; Because of the intramixing, leaving the silane-PVA/PVAc film is not complex anymore. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]