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

In this study, two types of composites, polybutylene terephthalate (PBT) and epoxy resin (ER), reinforced with 20% of glass fiber (GF) are used as the comparative research objects. Their mechanical properties after thermal aging at 85~145 °C are evaluated by tensile strength and fracture morphology analysis. The results show that the composites have similar aging laws. The tensile strength of GF/PBT and GF/ER decrease gradually with the increase of aging temperature, while their elastic moduli are independent of the thermal treatment temperature. Scanning electron microscopy study of the fracture surface shows that separation of glass fiber from PBT and ER matrix becomes more obvious at higher aging temperature. The fibers on the matrix surface appear clear and smooth, and the whole pulled out GFs can be observed. As a main mechanical strength degradation mechanism, the deterioration of interface adhesion between the matrix and GF is discussed. A large difference in coefficients of thermal expansion of the matrix and GF is a main factor of the mechanical degradation. [ABSTRACT FROM AUTHOR]

In the present work, short glass fiber is superficially modified with different concentrations of polyhedral oligomeric silsesquioxanes (Trisilanol–Isobutyl, TSI-POSS) for processing as a filler in a polypropylene matrix (PP). It is observed that increasing the amount of TSI-POSS increases the fracture point and tensile strength; the opposite is the case for the strength impact property. The behaviors of both dynamic mechanical and thermal analyses are also observed. The flame behavior, i.e., the burning rate, decreases with increasing TSI-POSS in the polymers. [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]

The present research presents an examination of the consequential effects brought about by the introduction of short-cut E-glass fibers (GF) on the properties of high-dielectric constant, high-thermal conductivity microwave composite systems (x GF/(8- x)BNNS/78 wt%ST/polyolefin, x = 0-8 wt%, BNNS: hexagonal boron nitride nanosheets). The GF is modified using KH550, with the success of the surface modification definitively confirmed by X-ray Photoelectron Spectroscopy (XPS) and Fourier Transform infrared spectroscopy (FTIR). All components are found to exhibit consistently ultra-high and stable dielectric constants within the 8–12 GHz frequency range (D k = 17.7–18.08). Based on thermogravimetry analysis (TGA) and dynamic mechanical analysis (DMA) results, the incorporation of modified GF improve the thermal stability of the composite materials, enhancing thermal decomposition temperature, residual carbon content and glass transition temperature. Furthermore, replacing BNNS with GF significantly amplifies the mechanical properties of the composite substrate. This substitution leads to a notable reduction in the coefficient of thermal expansion (CTE) in all directions while simultaneously increasing the bending and tensile strength. At the same time, the composites can maintain reasonably high thermal conductivity values. Overall, with a GF concentration of 4 wt%, the composite showcases an appreciable increase in dielectric constants (17.81), a high thermal conductivity (1.3 W/m·K) and enhances mechanical properties (cross-plane CTE: 15.44 μm/(m·°C), in-plane CTE: 26.06 μm/(m·°C), bending strength: 65.6 MPa, tensile strength: 17.42 MPa). Considering its superior performance metrics, the composite can be identified as an optimal choice for microwave composite dielectric substrate material. [ABSTRACT FROM AUTHOR]

Fiber-reinforced polymer composites are manufactured using various methods, with vacuum-assisted resin transfer molding (VARTM or VARIM). This study's primary focus lies in assessing how the orientation of sampling impacts the mechanical properties of glass fiber-reinforced pure and nanocomposites. 2 wt.% nano Al2O3- doped and non-doped composites were produced using the VARTM process. Tensile, flexural, and density test specimens were extracted from three distinct zones and two distinc direction those aligned horizontally to the resin flow (HRF) and those oriented vertically to the resin flow (VRF). Remarkably, results showed up to a 3.91% increase in values from samples in the third zone, particularly on the vacuum outlet side. To facilitate precise stress value comparisons across plates, uniform sample orientation and consistent zone selection are essential. [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]

• Adding 1 % nano Al 2 O 3 maintained mechanical properties by reducing water absorption. • Nano Al 2 O 3 enhances decomposition temperature by 8.35 % and acts as a thermal barrier. • 1 % nano Al 2 O 3 additive improves t g by 8.76 % in the hydrothermal aging environment. • Aging led to wear property deterioration, but nano Al 2 O 3 decreased this effect. Glass fiber composites are widely used in offshore structures for marine application due to their exceptional strength-to-weight ratio, corrosion resistance, and durability. As offshore structures are exposed to harsh environmental conditions, including saltwater, fluctuating temperatures, and hydrothermal influences, understanding the effects of aging on structural integrity on glass fiber composites becomes very important. In this study glass fiber-reinforced epoxy nanocomposites with 1 % and 2 % nano Al 2 O 3 reinforcement were produced using the vacuum-assisted resin transfer molding. These composites were subjected to a three-month aging process in artificial seawater at a temperature of 70 °C. Mechanical properties were assessed through Tensile and Flexural Tests, while thermal properties were analyzed via TGA, DTA, and DSC analysis. To examine the structural characteristics, Fourier Transform Infrared (FT-IR) spectrophotometry was utilized, and SEM analysis was conducted. Wear properties were evaluated through dry sliding wear tests. Water absorption properties were determined in a precisely controlled seawater bath. The findings reveal that the incorporation of 1 % nano Al 2 O 3 effectively diminishes the water absorption rate, thereby safeguarding the mechanical, thermal, and structural properties within a hydrothermal environment. [Display omitted] [ABSTRACT FROM AUTHOR]

The present investigation is aimed at evaluating the effect of styrene butadiene rubber, glass fibre, nylon fibre and hybrid reinforcement of glass and nylon fibre with 0.5 and 1.0 wt% on the impact, flexural, and compressive properties. A total of 19 groups were formed, including one control group and 18 study groups. All specimens were fabricated according to the standards and tests were performed. The enhancement of strengths were characterised by using scanning electron micrographs, FTIR results, XRD, and DMA tests. The degradability was studied using TGA/DTA analysis. The results were analysed using one-way ANOVA and Dunnett's post hoc multiple comparison test at p ≤ 0.05. The maximum impact, flexural, and compressive strength were found to be 3.234 ± 0.202 kJ/m2, 70.07 ± 0.7 MPa, and 84.929 ± 0.85 MPa for hybrid reinforcement of 0.5 wt% nylon fiber and 0.5 wt% glass fiber with 1.0 wt% of styrene butadiene rubber (SBR) mixed PMMA denture base material. Statistical analysis shows that the maximum mean impact strength, flexural strength, and compressive strength are about 84%, 58%, and 67% higher than the pure PMMA (control group). The maximum flexural modulus and compressive modulus are 914.4 MPa and 407.847 MPa for denture base material made of 1.0 wt% SBR, 1.0 wt% nylon fiber, 0.5 wt% glass fiber, and 0.5 wt% SBR, 0.5 wt% nylon fiber, respectively. The storage moduli of 1.0 wt% SBR, 1.0 wt% nylon fiber, and 0.5 wt% glass fiber-reinforced denture base material and pure PMMA are 0.096 and 0.422 at 79 °C, respectively, which indicates significant crosslinking of fiber and PMMA. The failure surfaces are characterized by a homogeneous distribution of fiber with increased surface roughness and fiber pullout, strong bonding, and well-dispersed SBR. [ABSTRACT FROM AUTHOR]