Polymer Matrix Composites Research Articles

Studies on Mechanical and Tribological Behaviour of Natural and Synthetic Based Hybrid Polymer Matrix Composites

Studies on Mechanical and Tribological Behaviour of Natural and Synthetic Based Hybrid Polymer Matrix Composites

Enhancing mechanical properties and tribological performance through boron carbide hybridization in Novolac matrix graphite composites under dry sliding condition

This study extensively investigates the effects of 10 wt% graphite reinforcement and varying B4C content (1 wt%, 2 wt%, 4 wt%) on the properties of Novolac matrix polymer composites prepared by mechanical milling-assisted hot pressing. The microstructures, wear surfaces, wear debris, and fracture surfaces of the produced polymer composites were examined using SEM and EDS. The density measurements were conducted according to the Archimed’s principle. Their tribological behavior was evaluated with a reciprocating ball-on-flat sliding wear test at 50 N, 75 N, and 100 N loads. After the wear tests, surface topography was analyzed in 3D with an optical profilometer. The results indicated that composites with 2 wt% B4C had the lowest specific wear rate and the highest wear resistance.

Impact of Different Mineral Reinforcements on HDPE Composites: Effects of Melt Flow Index and Particle Size on Physical and Mechanical Properties.

The use of mineral reinforcements in polymer matrix composites has emerged as an alternative for sustainable production, reducing waste and enhancing the physical and mechanical properties of these materials. This study investigated the impact of the melt flow index (MFI) of HDPE and the particle size of two mineral reinforcements, Bahia Beige (BB) and Rio Grande do Norte Limestone (CRN), on the composites. All composites were processed via extrusion, followed by injection, with the addition of 30 wt.% reinforcement. Chemical analyses revealed similar compositions with high CaO content for both minerals, while X-ray diffraction (XRD) identified predominantly calcite, dolomite, and quartz phases. Variations in the MFI, reinforcement type, and particle size showed a minimal influence on composite properties, supported by robust statistical analyses that found no significant differences between groups. Morphological analysis indicated that composites with lower MFI exhibited less porous structures, whereas larger particles of BB and CRN formed clusters, affecting impact resistance, which was attributed to poor interfacial adhesion.

Significant sliding speed effect on the friction and wear behavior of UHMWPE matrix composites

PurposeWith the rapid development of the pipeline transportation and exploitation of mineral resources, it is urgent requirement for the high-performance polymer matrix composites with low friction and wear to meet the needs of solid material transportation. This paper aims to prepare high-performance ultrahigh molecular weight polyethylene (UHMWPE) matrix composites and investigate the effect of service condition on frictional behavior for composite.Design/methodology/approachIn this study, UHMWPE matrix composites with different content of MoS2 were prepared and the tribological performance of the GCr15/composites friction pair in various sliding speeds (0.025–0.125 m/s) under dry friction conditions were studied by ball-on-disk tribology experiments.FindingsResults show that the frictional behavior was shown to be sensitive to MoS2 concentration and sliding velocity. As the MoS2 content is 2 Wt.%, composites presented the best overall tribological performance. Besides, the friction coefficient fluctuates around 0.21 from 0.025 to 0.125 m/s sliding speed, while the wear rate increases gradually. Scanning electron microscopy images, energy-dispersive spectroscopy and Raman Spectrum analysis present that the main wear mechanisms were abrasive and fatigue wear.Originality/valueThe knowledge obtained herein will facilitate the design of UHMWPE matrix composites with promising self-lubrication performances which used in slag transport engineering field.

Solvent Vapor Annealing and Plasma Treatment Stabilize Silver Nanowire Layers

AbstractSilver nanowires (AgNW) find use in transparent conductive electrodes with applications in solar cells, touch screens, and wearables. Unprotected AgNW are prone to atmospheric corrosion and lose conductivity over time. Known passivation techniques either require submersion of pre‐deposited AgNW in liquid compounds or the modification of AgNW inks prior to deposition, which alters viscosity and complicates deposition. Here, new possibilities for stabilization of pre‐deposited AgNW networks without need for submersion are explored. It is demonstrated that AgNW networks can be stabilized either by argon or hydrogen plasma treatment or by solvent vapor annealing with ethanol, methanol, or ethyl acetate. These treatments yielded stable electrical resistance over at least nine weeks, whereas untreated or thermally annealed AgNW layers quickly lost conductivity. The potential of solvent vapor annealing is further explored by demonstrating a new processing technique for stable polymer matrix composites containing AgNW. Co‐deposited layers of AgNW with polystyrene microbeads are annealed in ethyl acetate vapor to stabilize the AgNW while at the same time merging polymer beads into a closed film around the AgNW. The resulting composites maintained stable resistance and transmittance for at least seven weeks.

Enhanced Mechanical Properties of Carbon Fiber/Epoxy Nanocomposites Modified with Amine-Functionalized Graphene

<div>Since the beginning of time, people have desired the best materials for production. Metals are often too heavy to be used in manufacturing. Polymer matrix composites (PMC) can be considered more dependable than metals in practical applications because of their high strength-to-weight ratio so it is a good alternative of metals. The article’s objective is to investigate the various PMC properties that are reinforced with carbon fiber. CFRP (Carbon fiber-reinforced polymer) was first made using the hand layup method with carbon fiber as a reinforcement and epoxy resin as a matrix after a thorough literature review. As CFRP have higher stiffness and superior “strength-to-weight ratio,” fiber-reinforced polymer (FRP) composites perform notably better than various conventional metallic materials. The qualities of the matrix can be changed to enhance the characterization of FRP composites. The mechanical qualities of FRP composites have risen as a result of significant advancements in the application of nanoparticles for betterment of the matrix and various tests were conducted to calculate the properties of the composite.</div>

A comparison of additive manufactured to injection molded Martian regolith based polymer matrix composites

The completed study investigated the creation of Martian regolith simulant composite parts using injection molding and additive manufacturing. Traditional manufacturing techniques such as injection molding are not feasible on the Martian surface therefore in-situ processes must be developed using additive manufacturing processes to prepare habitats prior to having a human presence on the surface. The goal of this study was to investigate the impacts of additive manufacturing on the material property values between parts made using traditional injection molding and additive manufacturing. Martian regolith simulant composite pellets were created by combining a Martian regolith simulant at 40 wt% loading with polypropylene via twin screw extrusion. This material was then used to create test specimens using injection molding and additive manufacturing. Samples underwent tensile, flexural, Izod impact, and immersion density tests according to ASTM International and standardized test instructions. Additive manufactured parts saw a nearly 40% reduction in tensile and flexural strength with more than double the tensile modulus when compared to injection molded parts. The flexural modulus for additive manufacturing was around 36% that of the injection molded part with a minor decrease in density of around 13%. The collected test results suggested that while there were differences in the material property values between the manufacturing processes, a more interesting foaming behavior of the extrudite was observed during the additive manufacturing process resulting in an extremely rough and pitted surface. This rough surface finish was a stark comparison to the smooth injection molded parts. This observed foaming behavior in the polymeric composite material during thermal processing prompted the theory that thermal releases from the Martian regolith simulant was the most likely cause of the observed differences. Pellet surface moisture tests, Martian regolith simulant thermogravimetric analyses, and literature reviews of thermal decomposition of the Martian regolith simulant constituents revealed that most likely olivine releases oxygen and hydrated silica releases water during the thermal processing of the Martian regolith simulant composite. During a closed mold process such as injection molding, these volatile gases are forced out of the part by the pressures of the molding process, but in an open to atmosphere process such as additive manufacturing these gases foam to the surface during cooling leaving the part with an inferior surface finish.

Polymer Matrix Composites: The case of pentamodes

Pentamodes are known for their almost zero shear modulus. Polymer Matrix Composites are renowned for multiple advantages, such as their ability to withstand harsh conditions and prolonged usage. In the current study, a combination of these two technologies, i.e. Pentamode-based Polymer Matrix Composites (PPMCs) are proposed for application in seismic isolation. Bearings composed of pentamode layers embedded into polymer matrices are proposed. It is demonstrated that PPMCs feature a shear response improved up to 33 % compared to conventional pentamode specimens. By adding stiffening plates to PPMCs their compressive response can be improved up to 24 %. PPMCs with layers rotated every 45° are suggested to overcome the pentamodes’ anisotropy and their shear stiffness is proved to be increased by up to 26 %. The bearings’ failure mechanisms confirm the aforementioned findings. Real-life seismic excitations illustrate the applicability of PPMCs in seismic isolation and highlight the shear response improvement of up to 39 % offered by PPMCs compared to conventional pentamode devices.

Effect of ZrO2 on Radiation Permeability Properties of Polypropylene

The study investigates the radiation permeability properties including mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), tenth value layer (TVL), half value layer (HVL), fast neutron cross section (FNRC), and mean free path (MFP) of polypropylene (PP) polymer, as well as the produced polymer matrix composites (PP+5% ZrO2, PP+10% ZrO2, PP+15% ZrO2). The studied materials were examined by considering their effect on radiation permeability against gamma and neutron radiation. Additionally, powder size, Archimedes principle (density), XRD, DSC, ATR, and DTA-TG analyses were performed. According to the radiation permeability results of the studied four materials, PP + 15% ZrO2 was found to have the highest LAC values, while PP was found to have the lowest LAC values. The FNRC values of the PP, PP+5% ZrO2, PP+10% ZrO2, and PP+15% ZrO2 materials were found to be 10.038 cm-1, 12.651 cm-1, 15.002 cm-1, and 17.091 cm-1, respectively. The most suitable material for gamma and neutron shielding was found to be 15% ZrO2 reinforced material.

Transparent Multilayer Acrylic Composites Reinforced with Poly(Acrylated Urethane) Filled Low Grammage Bacterial Cellulose Nanopaper.

Cellulose nanopaper is a material structure that possesses high mechanical performance and is widely regarded as a promising 2D reinforcement for polymer matrix composites. This work explores the use of low grammage bacterial cellulose (BC) nanopaper as reinforcement for poly(acrylated urethane) interlayer adhesive to increase the impact performance of multilayer acrylic composites. The BC nanopaper is impregnated with an acrylated urethane resin and laminated between acrylic sheets to create BC/acrylic composites consisting of one, three, and five layers of BC nanopaper-reinforced poly(acrylated urethane) interlayer adhesive(s). Both the poly(acrylated urethane)-filled BC nanopaper interlayer adhesive and the resulting laminated acrylic composites are optically transparent. The incorporation of BC nanopaper into the poly(acrylated urethane) interlayer adhesive improves the tensile modulus by eightfold and the single-edge notched fracture toughness by 60% compared to neat poly(acrylated urethane). It is also found that using poly(acrylated urethane)-filled BC nanopaper interlayer adhesive proves beneficial to the impact properties of the resulting laminated acrylic composites. In Charpy impact testing, the impact strength of the multilayer acrylic composites increases by up to 130% compared to the "gold-standard" impact-modified monolithic acrylic, with a BC loading of only 1.6wt%.

Raman spectroscopic stress mapping of single high modulus carbon fibre composite fragmentation in compression

Fragmentation of high modulus carbon fibres is relevant to the failure mechanisms of advanced polymer matrix composites in compression. In situ spatially-resolved Raman spectroscopy during the fragmentation of model single fibre composites is used to map local stress distributions during failure events. The characteristic graphitic band (the G band) located around 1580 cm−1 is associated with the in-plane carbon-carbon bonds; this band shifts its position, and can be calibrated, with the local axial stress in the fibre. The analysis maps the evolution of local stresses with increasing overall composite compression strain, identifying a series of critical events, including fibre fracture, interfacial debonding, and the formation of inter-fragment ‘wedges’. Fitting shear lag models provides interfacial shear strength values. Multiple failure maps of two examples of high modulus PAN carbon fibres (M46J and M55J) demonstrate the possibility of local fragment bending due to fragment end contact. A timeline of potential fragmentation events is proposed for carbon fibres undergoing compression.

High-Permittivity Polymer–Matrix Composites for the Development of Triboelectric Nanogenerators (TENGs) with Enhanced Performance: A Review

High-Permittivity Polymer–Matrix Composites for the Development of Triboelectric Nanogenerators (TENGs) with Enhanced Performance: A Review

The Mechanical and Physical Properties of 3D Printing Filament made from Recycled Polypropylene and Ground Tyre Rubber Treated with Alkali

When molten, used vehicle tyres are unable to decompose or be recycled. Despite global efforts to find new uses for these materials, many worn tyres are still dumped in landfills. Therefore, this study proposes using ground tyre rubber (GTR) as a fill material for recycled polypropylene 3D printing filament. The filament composite’s physical and mechanical properties will be assessed in this investigation. GTR is expected to give the filament elastic characteristics, which could lead to rubber-like filaments. This study filled recycled polypropylene (rPP) polymer matrix composites with GTR to make filament. The mechanical and physical properties of a 3D-printed specimen made from rPP and GTR filament with varying compositions were analysed. Compared to pure rPP, rPP/GTR samples with 3 wt% GTR had a maximum tensile strength of 716.76 MPa. The flexural test findings showed that rPP/GTR with 3 wt% GTR had the highest flexural strength at 80.53 MPa, followed by rPP/1 wt% GTR at 65.38 MPa. In physical tests, the rPP/GTR at 5 wt% GTR had the highest water absorption at 5.41 %, and the wt% of GTR connected directly with water absorption. This study has shown that affordable, environmentally friendly rPP/GTR filaments can be developed with less amount of GTR content (3 wt%) and used for 3D printing applications, helping to lessen the impact of plastic and waste while having valuable mechanical and physical properties that are comparable to those of the pure polypropylene material produced.

Multiscale analysis of the compressive behaviour of polymer-based composites reinforced by hybrid Al2O3/Al fibres

Metal fibre reinforcements to polymer matrix composites (PMCs) bolster architectural flexibility and functionality affordably but feature a relatively weak interfacial bonding if not surface treated. This work demonstrates that Plasma Electrolytic Oxidation is promising to prepare woven hybrid Al2O3/Al reinforcements for PMCs. The compressive behaviour (a critical design parameter in structural design) of PMCs reinforced by ∼9–13 vol% γ-Al2O3/Al fibres with different oxide-to-metal ratios (∼20–50 vol%) is evaluated. The majority of fibres with the oxide ratio of 20 % failed in micro-buckling mode at interlacing points. Compared to Al reinforcements, the hybrid Al2O3/Al fibres increased the specific compressive strength (σc/ρ) and modulus (Ec/ρ) of the composite by ∼15 % and ∼58 %, respectively. Oxide shells thicker than 15–20 μm limited further enhancement due to fibre failure by shear-induced rupture. Thinner shells on Al reinforcements are recommended for PMCs used to manufacture structural components in mechanical engineering applications.

A novel normalized fatigue progressive damage model for complete stress levels based on artificial neural network

The fatigue life model and fatigue stiffness degradation model are most crucial components in establishment of fatigue progressive damage model (FPDM). Based on numerous static and fatigue experiments of glass fiber reinforced polymer-matrix composites (GFRP) 3232A/Glass, a novel normalized FPDM for complete stress level based on artificial neural network (ANN) has been built: (1) By analyzing fatigue experimental data, the construction method of fatigue life model is deeply investigated. Furthermore, a normalized fatigue life model (NFLM) predicting fatigue life considering simultaneously tension–tension (T-T) fatigue and compression-compression (C–C) fatigue is developed, which has been validated by experimental data. It is expected to reduce experimental time and costs by nearly half; (2) To fully consider the influence of stress level and remove the constraint of the shape of stiffness degradation function, the traditional models are no longer suitable. Thus, a fatigue stiffness degradation model based on ANN (FSDM-ANN) has been constructed, which overcomes drawbacks of the traditional models. The results predicted by FSDM-ANN are consistent with fatigue data in different stress levels; (3) Due to distortion of the fatigue life prediction of extreme high-cycle and low-cycle, an empirical data extrapolation method is proposed here to construct a modified FSDM-ANN, which greatly improves prediction accuracy of stiffness degradation for complete stress levels.

Intrinsically reactive hyperbranched interface governs graphene oxide dispersion and crosslinking in epoxy for enhanced flame retardancy

Enhancing the flame retardancy of epoxy (EP) resins typically entailed a trade-off with other physical properties. Herein, hyperbranched poly(amidoamine) (HPAA) and phytic acid (PA) were used to functionalize graphene oxide (GO) via electrostatic self-assembly in water to prepare a phosphorus-nitrogen functionalized graphene oxide nanosheet (PN-GOs), which could be utilized as high efficient flame-retardant additive of epoxy resin without sacrificing other properties. The PN-GOs demonstrated improved dispersion and compatibility within the EP matrix, which resulted in significant concurrent enhancements in both the mechanical performance and flame-retardant properties of the PN-GOs/EP nanocomposites over virgin EP. Notably, the incorporation of just 1.0 wt% PN-GOs yielded a 20.4, 6.4 and 42.7 % increases in flexural strength, flexural modulus and impact strength for the PN-GOs/EP nanocomposites, respectively. Furthermore, simultaneous reductions were achieved in the peak heat release rate (pHRR) by 60.0 %, total smoke production (TSP) by 43.0 %, peak CO production rate (pCOP) by 57.9 %, and peak CO2 production rate (pCO2P) by 63.9 %. This study presented a facile method for the design of GO-based nano flame retardants, expanding their application potential in polymer-matrix composites.

Comparison of Mechanical Property Simulations with Results of Limited Flexural Tests of Different Multi-Layer Carbon Fiber-Reinforced Polymer Composites.

This article is focused on the experimental study of flexural properties in different multi-layer carbon fiber-reinforced polymer (CFRP) composites and correlations with the results of finite element method (FEM) simulations of mechanical properties. The comparison of the results shows the possibility of reducing the number of experimental specimens for testing. The experimental study of flexural properties for four types of carbon fiber-reinforced polymer matrix composites with twill weaves (2 × 2) was carried out. As input materials, pre-impregnated carbon laminate GG 204 T and GG 630 T (prepreg) and two types of carbon fiber fabrics (GG 285 T and GG 300 T (fabric)) were used. Multi-layer samples were manufactured from two types of prepregs and two types of fabrics, which were hand-impregnated during sample preparation. The layers were stacked using same orientation. All specimens for flexural test were cut with the longer side in the weft direction. Pre-impregnated carbon laminates were further impregnated with resin DT 121H. Carbon fabrics were hand-impregnated with epoxy matrix LG 120 and hardener HG 700. To fulfill the aim of this research, finite element method (FEM)-based simulations of mechanical properties were performed. The FEM simulations and analysis were conducted in Hexagon's MSC Marc Mentat 2022.3 and Digimat 2022.4 software. This paper presents the results of actual experimental bending tests and the results of simulations of bending tests for different composite materials (mentioned previously). We created material models for simulations based on two methods-MF (Mean Field) and FE (Finite Element), and the comparative results show better agreement with the MF model. The composites (GG 285 T and GG 300 T) showed better flexural results than composites made from pre-impregnated carbon laminates (GG 204 T and GG 630 T). The difference in results for the hand-impregnated laminates was about 15% higher than for prepregs, but this is still within an acceptable tolerance as per the reported literature. The highest percentage difference of 14.25% between the simulation and the real experiment was found for the software tool Digimat FE 2022.4-GG 630 T composite. The lowest difference of 0.5% was found for the software tool Digimat MF 2022.4-GG 204 T composite. By comparing the results of the software tools with the results of the experimental measurements, it was found that the Digimat MF 2022.4 tool is closer to the results of the experimental measurements than the Digimat FE 2022.4 tool.

Reversible shape memory behavior of knitting-fabric reinforced polymer matrix composites

Reversible self-shaping behavior has been occurred with chemically crosslinked polymers and multi-layer structures while this behavior is difficultly realized for the fabric reinforced polymeric composites. In this work, a thin weft plain knitted fabric reinforced shape memory polymer composites (SMPCs) with reversible shape memory effect were developed. The effect of sizes, knitting densities and actuated temperatures on reversible shape memory behavior of SMPC was investigated. The results show that the maximum self-bending curvature of SMPCs is 35.8 m-1 and the shape recovery ratio reaches 82.2 %. A simplified finite element model was established to simulate and analyze the process of self-bending with heating and self-recovery with cooling of SMPC. Interestingly, the SMPC in wale direction (90°) has the inverse self-bending curvature of −18.4 m-1 as compared with that of SMPC in course direction (0°). The complex double curvature self-bending behavior of SMPC was also demonstrated. This work helps to broaden the development and research of reversible shape memory composites.

ПОЛІМЕРИ В БІОМЕДИЧНІЙ ІНЖЕНЕРІЇ: МАТЕРІАЛИ ДЛЯ ВИРОБНИЦТВА ПРОТЕЗІВ ТА ОРТЕЗІВ (ОГЛЯД)

Amputation of limbs as a result of the muscovites war as well as appearance of various injuries, accidents, diseases is becoming widespread in Ukraine. In this regard, the problem of high-quality prosthetics became relevant. The review highlights the main types of prostheses, orthoses and materials applied for their production also the problems concerning the research of materials and products. Studies conducted over the past 30 years show that prostheses are being made mainly of metal and polymer composites, as well as natural fiber-reinforced composites. Studies have shown that the good mechanical properties of polymer matrix composites reinforced with fibers of various nature have made such materials promising for the prosthetics application.

Fabrication and Characterization of Natural Fiber-Polymer Composites for Prosthesis Socket Application

ABSTRACT A natural fiber-reinforced composite from a locally available false banana plant is developed for a prosthesis socket application. Four batches of composite samples are fabricated by arranging the longitudinal uniformly distributed unidirectional false banana fibers in four orientations (0°, 90°, ±45°, 0°/90o). The composites’ mechanical and physical properties, such as tensile strength, compression strength, flexural strength, impact resistance, and the effect of chemical treatment on water absorption, are investigated. The results are compared with E-glass fiber-reinforced polymer matrix composite. The false banana fiber-polymer composites with a 0° fiber orientation have a tensile strength of 86.81 MPa, less than 9% lower than E-glass-fiber composites (95.44 MPa), and an impact resistance of 6.25 J, 10% higher compared to the E-glass fiber polymer composites (5.70 J). In addition, the treated false banana fiber-polymer composite absorbed 70% less water than the untreated false banana fiber-polymer composite. It is observed that the fiber treatment has increased the polymer–fiber interaction and the interface strength of the false banana fiber-polymer composites.