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While improving the thermal conductivity of composites, single‐size carbon nanotubes (CNT) often degrade their mechanical properties due to the agglomerates. To overcome this limitation, this study reported thermoplastic resin matrix composites synergistically reinforced with small, medium, and large‐size carbon nanotubes (S‐CNT, M‐CNT, and L‐CNT). Using the thermal conductivity (λ) and mechanical properties (flexural strength [F], compressive strength [C] and tensile strength [T]) as the response values, we conducted 21 sets of mixing design experiments and developed the associated quadratic term models. Further multi‐objective optimization was carried out for the above response values. Optimized multiscale CNT synergistically modified composites (S‐CNT, M‐CNT, and L‐CNT contents of 1.25, 7.02, and 2.56 wt%) exhibited a λ value of 1.168 W/mK, which was 121% higher than that of pure composite and also superior to the same content of S‐CNT‐ (1.031 W/mK), M‐CNT‐ (1.016 W/mK), and L‐CNT‐modified composites (0.983 W/mK). Additionally, the optimized composite demonstrated excellent mechanical properties (F = 1482 MPa, C = 848 MPa, and T = 1759 MPa), which were 13%, 11%, and 13% higher than those of the pure composites, respectively, and also surpassed those of the S‐CNT‐, M‐CNT‐and L‐CNT‐modified composites. Highlights: Using three different scales of carbon nanotubes modified CF/PPBESK composites.Polynomial modeling of composite's thermal conductivity and mechanical properties.Synergistic interactions between carbon nanotubes to improve the composite's thermal conductivity and mechanical properties. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) composite serve as widely used filaments in fused deposition modeling (FDM) 3D printing. This study investigates the enhancement of PLA composite's comprehensive mechanical properties and thermal stability through the incorporation of carbon fiber (CF). The influence of FDM process parameters on the mechanical properties of PLA composite is also analyzed. Results show that adding 5 wt.% CF significantly enhances the stiffness and comprehensive mechanical properties of PLA composite. The order of printing factors affecting the tensile strength of the PLA composite product is as follows: printing layer thickness, bottom plate temperature, printing speed, and nozzle temperature. Finally, optimal tensile strength is achieved under specific conditions: 0.1 mm layer thickness, 60 °C bottom plate temperature, 40 mm/s printing speed, and 215 °C nozzle temperature. [ABSTRACT FROM AUTHOR]

Composites are fabricating by reinforcing waste bambara nut shell powder (BNSP) as a bio-filler into an epoxy resin matrix. The composite is fabricated by varying the mass fractions of filler in the range of 5–35 wt%. The effects of bio-filler content on physical, mechanical, and thermal properties are evaluated. The studies reveal that the tensile strength, tensile modulus, flexural strength, and impact strength increased with increasing bio-filler content. The highest mechanical properties of BNSP-loaded epoxy composites are achieved at bio-filler mass content of 15 wt%, whereas hardness increased for 5–35 wt% with peak value at 35 wt%. The water absorption and thickness swelling of the BNSF/epoxy composites increased with increasing bio-filler contents, while the density decreased with an increase in bio-filler content. The TGA results revealed that an increasing bio-filler content decreased thermal stability, whereas the Tg and Tm of the composites increased with increasing bio-filler content. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of fiber surface treatment on various properties of hair fiber reinforced composites. Human hair fiber reinforced modified epoxidized soybean oil based composites were prepared by compression molding technique. Acid treatment of hair fibers was carried out by using three different concentrations of HCl solution (0.25%, 0.75%, and 1%, respectively) in order to achieve improvement in adhesion between the fiber and the matrix. Epoxidized soybean oil was modified using methacrylic acid and methacrylic anhydride to form methacrylic anhydride modified epoxidized soybean oil. Rosin acid derivative (a rigid comonomer) was prepared and used as a crosslinker. Fourier‐transform infrared spectroscopy was carried out to study the interaction among the components of the composites. Various properties, namely, mechanical, thermal, flame resistance, and chemical resistance were checked. Scanning electron microscopy of the fractured surface of the composites was carried out to examine the morphologies. Hair fibers treated with 0.75% of HCl showed maximum improvement in all the properties and could be employed as reinforcement in various composites to be used for structural applications. [ABSTRACT FROM AUTHOR]

Highlights The objective of this study is to improve the properties of polylactic acid (PLA), a biopolymer produced from renewable resources, without compromising its environmentally friendly “natural composite” properties. The aim was to expand the application range of PLA by making it suitable for the production of high performance composites. With this in mind, it was decided to use inorganic and environmentally friendly materials such as basalt fiber (BF) and boric acid (BA) as reinforcements. Adhesive wear and tensile tests were used to investigate the tribological and mechanical performance of the composites. Differential scanning calorimetry (DSC) and dimensional stability analysis (DSA) methods were used to investigate the thermal properties. Scanning electron microscopy analysis was also used to investigate the morphological properties of the samples. In addition, a matrix modification process using Joncryl®, an epoxy‐based chain extender chemical, was applied to enhance the interfacial interaction between the composite components and improve the composite properties by improving the dispersion of reinforcing materials. As a result of the characterization tests, it was observed that a significant improvement in the properties of the material type containing 10 wt% BF, 0.25 wt% BA and 2 wt% Joncryl® was achieved. A 19% increase in tensile strength of this type of material was observed compared with unreinforced PLA, while the sharp peak increase in the coefficient of friction (COF) curve was shifted from 20 m to 60 m. As a result, it has been presented that environmentally friendly and inorganic materials such as BF and BA can be used to produce composite materials that will serve sectors where the need and use of high performance materials is intense, especially in the automotive, aerospace and aviation sectors. The properties of PLA matrix composites were improved by the simultaneous use of BF and BA and the addition of Joncryl®. The structural properties of PLA, an environmentally friendly polymer, have been improved without compromising this characteristic. PLA matrix natural composites with performance that can be used in the automotive, aerospace and aviation sectors have been developed. [ABSTRACT FROM AUTHOR]

The main aim of the present work is to evaluate and characterize the mechanical, morphological and thermal properties of wastes coming from the textile industry, mainly composed of cotton and polyester. These wastes will be thereafter implemented in commodity plastic such as polyamide, in order to develop new formulations of environmentally friendly materials. The composites were produced by extrusion and injection-molded processes in amounts between 15 wt.% and 60 wt.% of textile waste. With the objective of improving the properties of the materials, silanes were used as a compatibilizer between the textile fibers and the polymeric matrix. The effect of the compatibilizer in the composites was studied together with the effect of the amount of textile fiber added to the composites. Mechanical, thermal, morphological and wettability properties were analyzed for each composite. The results show that the use of silanes improves the interaction especially in those composites with a higher amount of textile waste, offering a balanced mechanical behavior with significantly high quantities. On the other hand, the melting temperature does not vary significantly with the introduction of silanes and textile waste content, although the incorporation of textile waste slightly reduces up to 23% the degradation temperature of the resulting composites. The wettability of the composites is also increased up to 16% with the incorporation of textile waste. Finally, the appearance of the composites with textile waste is strongly influenced by the incorporation of the reinforcement, offering shades close to dark brown in the whole range of compositions. [ABSTRACT FROM AUTHOR]

Hybridization of natural fibers with ceramic materials for reinforcing composites allows the optimization of the properties of these materials. For this reason, the present study aims to investigate physical, mechanical, water absorption, swelling and thermal properties as well as morphological characteristics of a hybrid Paederia foetida fibers–alumina powder (PFs–Al2O3)‐reinforced epoxy composite. Epoxy resin served as the matrix, while PFs and Al2O3 were employed as reinforcement. Five types of composites were fabricated using the hot‐pressing technique. The corresponding ratios of PFs:Al2O3 volume fractions (%) considered here were 0:40 (SFA), 10:30 (SFB), 20:20 (SFC), 30:10 (SFD) and 40:0 (SFE). The results reveal that the density of the hybrid PFs–Al2O3 composites decreased for increasing volume fractions of PFs: from 2.173 g cm−3 of SFA to 1.042 g cm−3 of SFE. The highest values of tensile strength (i.e. 49.085 MPa), tensile elastic modulus (i.e. 1.431 GPa) and impact strength (24 kJ m−2) were obtained for the SFD composite material with 30% volume fraction of PFs and 10% volume fraction of Al2O3: this happened because interface bonds between PFs, Al2O3 and epoxy phases achieved their optimal configuration. Overall, mechanical properties of the hybrid PFs–Al2O3‐reinforced epoxy composites were superior to those of composites reinforced only by PF fibers or only by Al2O3. Water absorption and swellability reached their maximum values at the steady state occurring after tested samples remained immersed in water for 820 h. The SFE composite reinforced only by PFs presented the highest water absorption and swelling (i.e. 6.034% and 5.81%, respectively) while for all other hybrid composites (SFD, SFC and SFB) these two quantities remained below 5%. Density and volume fraction of voids of hybrid PFs–Al2O3‐reinforced composites were consistent with the corresponding properties of the composites reinforced only by Al2O3 or PFs. SFD was also the most thermally stable material. Scanning electron microscopy observations of fractured surfaces indicated that the microstructure of the PFs–Al2O3‐reinforced epoxy composites presents several voids, fiber pullouts and transverse fibers, which together optimize the mechanical response of the composite material. Remarkably, the SFD composite material was highly competitive with the most recently developed hybrid composites employing natural reinforcements. © 2024 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

The use of hybrid reinforcement in polymer composites has been getting attention due to its potential for weight and cost reduction while achieving improved design flexibility for mechanical and thermal properties. In this study, an interply hybridization of epoxy laminates was performed using layers of solid and hollow glass fibers. The structural and thermal performance of the resulting hybrid vascular composites was investigated. All composite parts were manufactured using vacuum‐assisted resin transfer molding (VARTM), following an interply hybridization plan for the stacking sequence of hollow and solid fiber layers. An expected decrease in flexural properties and thermal conductivity was observed for the laminates with completely hollow fibers. On the other hand, hybridization had a positive effect on the laminate properties. It was shown that hybrid vascular composites could be manufactured without a significant reduction in mechanical and thermal performance by a judicious hybridization plan. The optimum hybridization of the laminate achieved a 3.1% increase in the specific flexural strength and a 5.3% decrease in thermal conductivity while containing a vascular network that can be used for active thermal control. Highlights: A vascular interply composite structure consisting of hollow and solid fibers was manufactured and characterized for the first time.The I4 composite, vascularized through the middle layers of the laminate, has almost as much flexural strength as solid composite and much more specific flexural strength.The thermal conductivity of the I4 composite is almost as much as that of the solid composite.Functional composites for thermal management and smart applications can be manufactured using hollow fibers without sacrificing flexural strength and thermal conductivity with interply vascularization. [ABSTRACT FROM AUTHOR]

The main purpose of this research is to observe the effect of alkalisation of rattan, bamboo fibre, and eggshell particles addition in the fabrication of hybrid polyester laminated composite. A 5% NaOH treatment of fibres was conducted, and 5% eggshell particles was added to the composite. The FTIR analysis was done to reveal the presence of nanol, and thermal stabilities were evaluated by TGA, DTG and DTA. Furthermore, water absorption and biodegradability of the composite were also investigated. Mechanical properties were tested with compatible ASTM standards. The 5% NaOH treated 30 wt.% fibre- loading enhanced the tensile strength, flexural strength, impact strength, and hardness by 9%, 2%, 7%, and 4%, respectively compared to the raw composites. On the other hand, the addition of 5% eggshell particles decreased the tensile strength, flexural strength, impact strength, and hardness of the raw 30 wt% fibre-reinforced composite by 5%, 4%, 3%, and 2%, respectively In addition, the raw 30 wt% fibre-reinforced composite has the highest biodegradability, and water absorption percentage than the alkali-treated and eggshell added fibre-reinforced composite. The raw 30 wt% fibre-reinforced composite has dictated over the alkali-treated and eggshell added fibre-reinforced composite in terms of thermal stability. [ABSTRACT FROM AUTHOR]

Composite materials have garnered considerable interest in the thermal industry on account of their remarkable mechanical properties and thermal resistance. The objective of this research work is to analyse the impacts of integrating porcelain infill particles into basalt fibre-reinforced polymer (BFRP) composites. Particularly, the study aims to evaluate the consequential modifications in critical thermal and mechanical characteristics. The results of mechanical testing indicate that the incorporation of porcelain fillings significantly influences the composite tensile strength, flexural strength, and impact resistance. Additionally, by employing scanning electron microscopy (SEM), significant knowledge is acquired regarding the interfacial bonding mechanisms and microstructural properties of the filler particles, polymer matrix, and basalt fibres. Utilizing dynamic mechanical analysis (DMA), the maximal values of storage modulus (3429 MPa), loss modulus (489 MPa), and damping factor (0.17) are investigated in relation to the dynamic mechanical properties across a range of temperature conditions. The research additionally illustrates enhancements in thermal characteristics, including heat deflection temperature, thermal conductivity, and coefficient of linear thermal expansion, all of which are improved by 37% when porcelain infill is incorporated into the composite. In addition, thermal gravimetric analysis (TGA) examines the degradation and thermal stability properties of the composites over an extensive temperature spectrum, reaching a maximum of 390 °C. The insights derived from this analysis are particularly pertinent to applications involving thermal insulation. [ABSTRACT FROM AUTHOR]

The 2.5D oxide/oxide composites become attractive for their excellent integrity and mechanical properties. The thermal shock resistance performance of the material is very important in the actual high temperature application. In this work, the evolution of microstructure and mechanical behavior of the 2.5D oxide/oxide composites from thermal shock at different temperatures and cycles was investigated experimentally mainly by optical microscope, X-ray computed tomography and macro-mechanical tests. The thermal shock resistance mechanism of oxide/oxide composites was qualitatively explored. The results showed that cracks propagation was the main manifestation of thermal shock damage in composites. Compared with 2D composites, 2.5D composites exhibited the finite domain effect on crack propagation due to its reinforcement had certain fibers in Z -direction. This directly caused the critical thermal shock temperature difference of the 2.5D composites (∼900 °C) was more than twice that of the 2D oxide/oxide composites (∼400 °C). In addition, the finite domain effect also significantly reduced the damage growth rate of the 2.5D composites from cyclic thermal shock, highlighting its excellent thermal shock damage resistance. [ABSTRACT FROM AUTHOR]

The ZrO 2 fiber paper exhibits excellent thermal insulation properties, however, its limited mechanical strength and insufficient thermal stability hinder its widespread applications. The composite fiber papers, using mullite fibers possessing a high aspect ratio and exceptional thermal stability combined with ZrO 2 fibers, were fabricated via a vacuum-assisted filtration method. This method involved the successive stacking of composite fibers with alumina sol, using vacuum-induced directed water flow to create a layered structure reminiscent of nacre. The layered structure of the nacre, which demonstrates remarkable strength and hardness, has also served as a source of inspiration for the architectural design of the fiber paper. The tensile strength of pure ZrO 2 fiber paper was significantly enhanced by the addition of 7 wt% mullite fibers, resulting in a remarkable increase to 0.1805 kN/m. The paper exhibited exceptional resistance to bending, maintaining 96 % of its bending strength even after undergoing 100 cycles. The thermal shrinkage of the composite paper, containing 15 wt% mullite fibers, was reduced from 17.75 % observed in pure ZrO 2 fiber paper to a mere 1.32 % after undergoing heat treatment at a temperature of 1300 °C for 2 h. The composite paper, measuring 5 mm in thickness and consisting of 7 wt% compositions, displayed exceptional thermal insulation properties when exposed to a hot side temperature of 1370 °C. It effectively insulated temperatures up to approximately 1000 °C. [ABSTRACT FROM AUTHOR]

Lignocellulosic-based polymer composites have gained significant interest due to their ''green" character as a response to environmental concerns. A diverse array of lignocellulosic fibers is utilized, depending on fiber dimensions, chemical composition, moisture content, and the fiber–matrix interface. The aim of this study is to establish an alternative standardized methodology, aimed at comparatively estimating the performance of polymer composites through the examination of individual plant fibers. The fibers studied are ramie, hemp, flax, and kenaf, and HDPE-based corresponding composites were analyzed for their performance across various fiber-content levels (10, 20, and 30 wt.%). It was found that kenaf showcases the largest average fiber diameter, succeeded by hemp, ramie, and flax. Additionally, ramie and kenaf exhibit elevated levels of crystallinity, suggesting increased cellulose content, with kenaf having the lowest crystallinity index among the fibers compared. Based on Thermogravimetric analysis, ramie displays the lowest moisture content among the examined fibers, followed by hemp, flax, and ultimately kenaf, which is recorded to have the highest moisture content, while, similarly, ramie exhibits the lowest mass loss at the processing temperature of the corresponding composites. Composites containing fibers with smaller diameters and higher crystallinity indexes and lower moisture absorptions, such as ramie and hemp, demonstrate superior thermal stability and exhibit increased Young's modulus values in their respective composites. However, poor interfacial adhesion affects mechanical performance across all composites. Understanding fiber morphology, inner structure, and thermal stability is important for developing new composite materials and optimizing their selection for various applications. [ABSTRACT FROM AUTHOR]

Natural fiber composites are not suitable for use in industries due to their flammability and low thermal resistance. Inorganic metal‐based fillers are known to enhance the flammability and thermal resistance of composites, while the thermal and fire‐retardant properties of organic fillers are not commonly known. This study evaluated the mechanical, thermal, and flammability properties of Ceiba petandra fiber (CPF)‐reinforced composites, which were added with snail powder (SP). To study the thermal resistance of the composite, a dynamic mechanical analyzer (DMA) and thermogravimetric analysis (TGA) were applied. SP Filler concentration increased the composite's tensile strength and thermal resistance. DMA test results showed the same trend as the composite's density value. The flame rate parameters of the composite, including the percentage of char yield and the limitation index oxygen (LOI), rose as the SP filler increased. However, the flame rate of the composite dropped because SP filler inhibited the movement of oxygen, combustible gas, and polyester degradation products. The addition of organic fillers in natural fiber composites promises better flammability and thermal resistance. [ABSTRACT FROM AUTHOR]

In this paper, polysulfonamide‐based composite materials (SCF/PSAf composite) reinforced by the short carbon fiber were prepared. The mechanical properties and thermal stability of SCF/PSAf composite were characterized experimentally and compared with those of polysulfonamide‐based single‐polymer composites (PSA SPCs). Results showed that SCF/PSAf composites exhibit higher thermal stability due to the excellent thermal stability of SCFs. Furthermore, the additional short carbon fibers also considerably enhance the flexure strength of PSA SPCs due to the strong interfacial bonding between SCF and PSAf. The properties and understanding of SCF/PSAf composite obtained in this work can benefit further applications of this novel composite material. Highlights: SCF/PSAf composites are prepared by hot compression, and the adhesion between the PSA matrix and SCF is good.The flexural strength of the SCF/PSAf composite is about 2.5 times higher than that of PSA SPCs.The storage modulus of SCF/PSAf composites is about 3.5 times higher than that of PSA SPCs.The addition of short carbon fibers helps to improve the thermal properties of SCF/PSAf composites.SCF/PSAf composite has a stronger ability to resist deformation and a higher operating temperature than the PSA SPCs do. [ABSTRACT FROM AUTHOR]

The main objective of this study was to investigate the mechanical and thermal properties of bamboo, as well as interlaminar hybrid composites reinforced with both bamboo and synthetic fibres in an epoxy matrix. Bamboo and glass, aramid, and carbon bidirectional fabrics were used with a bi-component epoxy matrix to fabricate the composite materials using the vacuum bagging process. The synthetic fabrics were placed on the outer layers, while the bamboo fabrics were used as the core of the hybrid composites. The developed composites were characterized and compared in terms of morphological, physical, and mechanical properties. Further, thermogravimetric (TGA) analysis was used to measure and compare the degradation temperature of the composites studied. Finally, a Scanning Electron Microscopy (SEM) analysis was performed in order to examine the fracture surfaces of the specimens tested. It was found that the fibre hybridization technique significantly improved the general mechanical properties. TGA analysis showed an increase in the thermal stability of the composites obtained by incorporating the synthetic fibres, confirming the effect of hybridization and efficient fibre matrix interfacial adhesion. The results from this work showed that the use of synthetic fibre reinforcements can help to significantly improve the mechanical and thermal properties of bamboo fibre-reinforced composites. [ABSTRACT FROM AUTHOR]

This article explored the influence of curtain climber fiber and Biochar derived from Kigelia pinnata fruit fiber on a polyepoxide‐based composite material's thermal, mechanical, dielectric, and mechanical properties. Before commencing the composite production process, the surface of the curtain climber fiber underwent treatment with a solution consisting of 5% silane to enhance the bonding between the fiber and the matrix. The hand layup method and compression molding were used to produce the composite panels and tested according to the appropriate standards set by the ASTM. According to these findings, the mechanical properties of the composites were enhanced by adding 30% curtain climber fiber and 5% biochar. The load distribution on the fiber was consistent throughout. The composite's highest strength (EFB3) was 183 MPa, its modulus was 5.9 GPa, and its flexural strength and modulus were 216 MPa and 6.1 GPa, respectively. The impact intensity is 8 J, and the hardness value is 95 on the Shore D scale. In addition, the EFB3 had a maximum interlaminar shear strength of 35 MPa. According to the findings of the SEM surface analysis, the matrix molecules exhibit adhesion to the fiber, which indicates increased bonding. The thermal conductivity and dielectric properties were high for composite with higher biochar particle content. These waste biomass‐converted fruit fiber biochar and curtain climber industrial crop fiber epoxide composite materials may be utilized in a variety of sectors, including aerospace, automotive, household domestic product manufacturing, and defense sectors. Highlights: Extraction and silane treatment of curtain climber fiber.Producing biochar from waste biomass Kigelia pinnata fiber.Fabrication of polyepoxide composite.Siloxane layer improves the strength.Biochar improves the properties of composites. [ABSTRACT FROM AUTHOR]

Composites with good thermomechanical and UV-shielding properties are essential in fiber-reinforced composites. This paper focuses on composites' ultraviolet (UV) shielding efficiency with added Ce-Zr-Si oxide nanoparticles/epoxy resin. The Ce-Zr oxide nanoparticles were first functionalized with a silicon coupling agent and ethyl silicate to improve their dispersion and surface activity. In this work, we prepared epoxy nanocomposites with the addition of Ce-Zr -Si oxides(1,3,5,7 wt%) and found that the materials had good enhancement of the UV shielding properties of the epoxy resin matrix. Meanwhile, it was used in basalt fiber (BF)/epoxy composites prepared by the hot-pressing method, and surface treatment of basalt fibers was carried out. The results showed that the modified fiber composites could effectively enhance the thermomechanical properties of epoxy resin composites. It is noteworthy that the tensile strength and flexural strength of the hybrid composites reached their peak when 5 wt% Ce-Zr-Si was added, increasing by 13.8% and 33.67% respectively. The modified (BF)/epoxy composites exhibited improved thermal stability compared to pure epoxy resin, with the maximum weight loss temperature of BF-1/EP reaching 349°C. The T(UVA) decreased to 2.41%, while the T(UVB) decreased to 0.053%, and almost all the ultraviolet irradiation was blocked. These results show that our prepared composites have good thermomechanical and UV shielding properties. Highlights • Ce-Zr oxide nanoparticles were functionalized with a silicon coupling agent. • Ce-Zr-Si oxide was added to enhance the ultraviolet shielding efficiency. • Modified BFs were composited to improve thermomechanical properties. [ABSTRACT FROM AUTHOR]

In this work, the EVOH/Ti3C2 composite fibers were prepared via electrospinning and the effect of added Ti3C2 on the structure and properties of electrospun EVOH fibrous membranes was further investigated. The morphology, crystal structure, thermal properties, wettability, tensile properties, as well as air permeability and water vapor permeability of as-prepared EVOH/Ti3C2 composite fibers were studied. The Ti3C2 is uniformly loaded onto the surface and inside the composite fiber and affects the fiber diameters. Furthermore, The Ti3C2 self-orients along the fiber axis and does not change the crystal structure of the electrospun EVOH fibers, improving the crystallinity and thermal stability of the electrospun EVOH/Ti3C2 fibrous membranes. With the increase in the Ti3C2 concentration in the electrospinning polymer solution, the addition of Ti3C2 not only rapidly improves the wettability of the fibrous membranes, but also enhances their air permeability, compared with the pristine electrospun EVOH fibrous membranes. The experimental results provide theoretical guidance for the preparation of Ti3C2 composite fibers, and also expand the application of electrospun EVOH and EVOH/Ti3C2 fibrous membranes. [ABSTRACT FROM AUTHOR]

The effects of nanoclay (NC) addition on the thermal and mechanical properties of glass fiber-reinforced epoxy composites were investigated experimentally in this study. Nanocomposite plates were produced for this purpose using three different NC ratios (0.5%, 1%, and 1.5% by weight). Thermal characteristics of nanocomposites were investigated using dynamic mechanical analysis, differential scanning calorimetry, and thermogravimetric analysis. The mechanical and thermal results obtained from composites with three different NC ratios were compared with the results obtained from pure composites. The structures of nanocomposites were investigated with the help of SEM–EDS analyses. Furthermore, the effect of nanoclay on the failure behavior of composites was also investigated. In this study, the highest values in all mechanical properties were obtained from samples with a 1% NC-added. Obtained from 1% NC-added samples: tensile, compressive, shear strengths, elasticity modulus, shear modulus, and Poisson's ratio values were 31.06%, 4.25%, 14.30%, 7.35%, 11.94%, and 12.5% higher, respectively, than the values obtained from pure samples. Maximum loss modulus and maximum storage modulus were obtained from samples with 1.5% and 0.5% NC-added, respectively. In samples with 1.5% NC-added, the highest Tan δ value was obtained. Glass transition temperatures increased with the added NC. It was observed that the fiber–matrix interfaces were more clearly separated in the samples with 1.5% NC-added. [ABSTRACT FROM AUTHOR]

The utilization of plastic waste is another way to protect the ecology and reduce plastic pollution, which researchers and industries have been effectively focusing on for the last decade. Polyethylene terephthalate felt (PETf) is a packaging material abundantly utilized in the automotive sector and is released as waste, and its popularity as an industrial waste necessitates attention to proper disposal. Therefore, the current study utilized waste PETf as a reinforcement (5–15 wt%) for a polypropylene (PP) matrix using various molding approaches, in light of the higher aspect ratio of the fibers. In the first approach, the fibers were extracted from PETf through a mechanical process, and various percentages of PET felt fibers (PETff) were extruded with PP pellets, followed by injection molding. Second, PETf was directly laid on a PP sheet and processed by compression molding. The tensile strength, tensile modulus, and morphological and spectral properties of the fabricated composites were evaluated. Morphological and spectral analyses explain the distribution and interaction of the fibers in the PP matrix. The 10%PETff enhanced the tensile strength and modulus of PP by 37.3% and 52.15%, respectively. Conversely, the 1.5% malic anhydride‐g‐PP (MAPP)‐PP/PETf composites showed similar tensile behavior, with values of approximately 41.53 MPa and 1.6 GPa. In addition, the tensile strength significantly increased by 35.75% with the addition of MAPP. Overall, the current study demonstrates a well‐structured research design that effectively employs waste PETf as reinforcement for PP composites. The mechanical strength of these composites makes them highly versatile and renders them suitable for a wide range of applications, from automotive packaging to the manufacturing of high‐performance automotive components. Highlights: Utilized waste PET as reinforcement for manufacturing of PP composite.PET and PP interacted in a self‐reinforcing manner.Injection and compression molding techniques used for PET/PP composites.Repurposing waste PET by compression molding is eco‐friendly practices.PET fibers significantly improved mechanical properties of PP composites. [ABSTRACT FROM AUTHOR]

In this study, the mechanical properties and thermal stability of composite polypropylene (PP) drawn fibers with two different organically modified montmorillonites were experimentally investigated and optimized using a response surface methodology. Specifically, the Box-Behnken Design of Experiments method was used in order to investigate the effect of the filler content, the compatibilizer content, and the drawing temperature on the tensile strength and the onset decomposition temperature of the PP composite drawn fibers. The materials were characterized by tensile tests, thermogravimetry, and X-ray diffraction. Two types of composites were investigated with the only difference being the type of filler, namely, Cloisite® 10A or Cloisite® 15A. In both cases, statistically significant models were obtained regarding the effect of design variables on tensile strength, while poor significance was observed for the onset decomposition temperature. Nanocomposite fibers with tensile strength up to 540 MPa were obtained. Among the design variables, the drawing temperature exhibited the most notable effect on tensile strength, while the effect of both clays was not significant. [ABSTRACT FROM AUTHOR]

Dried leaves are the outstanding origin of cellulosic plant matter, and it is securing reputation as a renewable resource. Dried leaves fiber is suggested to possess the capability to substitute synthetic fibers in polymer laminates as a reinforcing component. The novelty of the present study reveals the effect of dried leaves fiber, cobalt, nickel, and ferrous reinforcement on the physical, mechanical, and thermal characteristics of epoxy, vinyl‐ester, and polyester polymers using artificial neural network (ANN) technique. These composites were fabricated using ultrasonication bath‐assisted wet layup method under ambient condition. The outcomes of this research exhibit that the dried leaves‐cobalt fillers reinforced in all three polymers possess higher mechanical and thermal stability characteristics when compared with other samples. The reason may be assigned to producing novel hydroxyl functional groups and strong interfacial bonding of fillers within the matrix as observed from Fourier‐transform infrared (FTIR) spectra and scanning electron microscope (SEM) micrographs, respectively. Moreover, as observed from the thermogravimetric analysis, the dried leaves‐ferrous filler‐reinforced polymer hybrid composites provided higher thermal stability. Statistical analysis was performed using the one‐way ANOVA technique and found that outcomes were significant statistically under the confidence level of 95%. Hence, this investigation not only emphasize the significance of investigating new polymer composites but also highlight the benefits of engaging advanced modeling to forecast the material characteristics precisely. Highlights: Dried leaves and cobalt/nickel/ferrous are applied reinforcement to polymers.Composites fabricated using ultrasonication bath‐assisted wet layup technique.LM Algorithm‐based ANN selected for predicting the best composite.Higher mechanical and thermal stability with dried leaves‐cobalt filler.One‐way ANOVA proved statistically significant within the material properties. [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 development of lightweight composites with desirable thermo‐mechanical properties is progressively increasing. Phthalonitrile (PN) based composites have shown great potential in this regard. However, the basic thermal properties of PN composites required for engineering design are not yet fully understood. In this work, we investigated the thermal stability, thermal expansion behavior and thermal conductivity of PN composites reinforced with carbon fiber (CF) and high silicon fiberglass (HSF) via combined experimental studies and numerical simulations. The results indicated that CF/PN performs better in thermostability than HSF/PN at temperatures below 500°C. Moreover, the incorporation of CF and HSF lowered the coefficient of thermal expansion (CTE) and thermal insulation of PN. At room temperature, the in‐plane CTE of CF/PN and HSF/PN were 1.97E‐6 and 9.24E‐6°C−1, respectively, while the out‐plane thermal conductivities of CF/PN and HSF/PN were 0.65 and 0.34 W/(m K). It is worth noting that an excessively high fiber volume fraction would lead to poor thermal insulation and lightweight properties of the PN composites, while a low fiber volume fraction would result in poor stiffness and thermal dimensional stability. Determined via TOPSIS model, a fiber volume fraction range of 50%–60% was ideal for both composites with comprehensive optimal properties, respectively. [ABSTRACT FROM AUTHOR]

This study was an attempt to combine fused deposition modelling and hot press moulding technique to fabricate hybrid polymer composites using acrylonitrile butadiene styrene (ABS) polymer, woven glass fibre (GF) and woven carbon fibre (CF). The composite specimens were subjected towere subjected to mechanical and thermal characterization.Tensile strength of GF/ABS and GF/CF/ABS composite were far higher than the virgin ABS. GF/ABS composites displayedimproved thermal resistance by giving a final residue of 42.36%, followed by GF/CF/ABS hybrid composites as per the thermogravimetric analysis. Thermomechanical analysis revealed the coefficient of thermal expansion in the order: ABS > GF/ABS > GF/CF/ABS. The entropy obtained from the DSC curve was of higher value for composites than the ABS. The ABS based composites fabricated from this technique can be applicable to structural parts in the automobiles, aircrafts, shipping vessels, etc. [ABSTRACT FROM AUTHOR]

In this work, epoxy (EP) resin composites with multi-scale reinforcements were prepared by hand lay-up and hot-pressing. The epoxy was reinforced with basalt fibers (BF) modified with a silane coupling agent (KH560). Carboxylated multi-walled carbon nanotubes (CNTs) were also grafted onto the surface of the modified BF using an impregnation method to achieve BF/CNTs multi-scale reinforcement. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) showed that KH560 was successfully grafted onto the BF surface. Scanning electron microscopy (SEM), indicated a better resin adhesion on the BF and thus a stronger interfacial interaction in the BF/CNTs-reinforced composite. It was observed that the mass fraction of KH560 was a significant parameter in achieving desirable CNT immobilization and mechanical properties of the composites. At an optimal mass fraction of KH560 (5%), the tensile, flexural, and interlaminar shear strength (ILSS) of the modified composite (BF-5%KH560-CNT/EP) increased by 12.5%, 20.9%, and 25.5% respectively compared with the BF-washed/EP composite due to more efficient load transfer. In addition, compared with BF-washed/EP, the decomposition onset temperature of BF-5%KH560-CNT/EP increased from 387°C to 396°C, the maximum decomposition rate temperature increased from 400°C to 408°C, and the residual weight increased by 5.8%. [ABSTRACT FROM AUTHOR]

This work presents the thermal and mechanical characterization of epoxy composites reinforced with different fillers developed by modifying thermo‐mechanically extracted bamboo micron fibers. The modification of bamboo fibers was done by adding carbon nanoparticles to their surface and also by making powdered fillers using the process of ball milling. A decrease in water absorption in case of surface coated bamboo fibers was observed. The glass transition behavior was enhanced for composites filled with milled bamboo fillers as compared to neat epoxy. Better mechanical properties were observed for composites reinforced with milled bamboo fillers compared to that of composites filled with bamboo fibers. The highest tensile strength (90.258 MPa) was observed for composites reinforced with 5 wt% of milled bamboo fillers depicting an increase of 93.01% compared to that of neat epoxy (46.762 MPa). Highlights: Bamboo fibers were modified with a sizing agent and carbon nanoparticles.A novel "milled bamboo filler" was produced and incorporated in composites.Thermal properties of epoxy composite were enhanced by the novel filler.Tensile strength of the composite was significantly enhanced.The novel filler has the future scope of application in various composite products. [ABSTRACT FROM AUTHOR]

The potential benefits of using zinc borate powder as filler material in the production of glass fiber‐reinforced composites were explored in this study. The epoxy matrix was filled with zinc borate powder at 5%, 10%, and 15% by weight, as part of the hand lay‐up approach followed by a compression molding process. Ultrasonication was used to mix the epoxy resin with zinc borate fillers. Both the elemental composition and morphological characteristics were studied using a scanning electron microscope and energy‐dispersive X‐ray analysis. The composite's density, tensile behavior, flexural behavior, impact resistance, and hardness were all measured experimentally. The potential incorporation of zinc borate particles resulted in a modest reduction in the void contents, in addition to enhancing the interfacial bonding in glass fiber‐reinforced composites as also a significant improvement in both the mechanical and thermal properties of the hybrid composites produced. The 10 wt.% zinc borate‐ filled glass fiber‐reinforced composites exhibited a significant rise in both ultimate tensile strength (227 MPa), ultimate compressive strength (239 MPa), and ultimate flexural strength (406 MPa) compared to the unfilled counterpart. The performance of the laminated composites was greatly improved by adding zinc borate powder particles to the matrix. Highlights: In the present work glass fiber was reinforced with zinc borate to explore the morphological, mechanical, and thermal properties.Ultrasonication was used to mix the epoxy resin and zinc borate fillers and the composites were manufactured by compression molding process.The addition of zinc borate resulted in an increase in tensile strength, flexural strength, and compressive strength.The thermal stability of the composites was increased by the addition of zinc borate to the glass matrix.The good bonding between the matrix and fiber resulted in improvements in various properties. [ABSTRACT FROM AUTHOR]

Natural fibre-reinforced composites have been developed by researchers and industries as a solution to reduce the use of synthetic fibres. Kenaf fibre is one of the most abundant natural fibres in Indonesia. This study aimed to obtain the mechanical and thermal properties of kenaf fibre-reinforced epoxy laminated composites fabricated using a vacuum-assisted resin infusion method. The alkaline-treated fibres were arranged in the orientations 0°/0°/0°/0° and 0°/90°/0°/90°. Density measurements, mechanical tests, and thermogravimetric analysis were carried out on the epoxy and the composites. The results of the mechanical testing showed that the tensile, flexural, and compression strengths of the kenaf fibre-reinforced epoxy composites with a 0°/0°/0°/0° fibre orientation were higher than those of the composites with a 0°/90°/0°/90° fibre orientation, with values of (96.61 ± 10.18) MPa, (131.01 ± 6.60) MPa, and (71.96 ± 5.50) MPa, respectively. Scanning electron microscope observations showed that the composites had good fibre-matrix adhesion. The thermal stability of the epoxy was enhanced from 557 °C to 571 °C by incorporating kenaf fibre with 0°/0°/0°/0° orientation. With reference to the Indonesian National Standard 01-4449–2006, the two composites could be classified as T2 45 High Density Fibreboard. [ABSTRACT FROM AUTHOR]

The main objective of this research centered on investigating the effect of the addition of multi-walled carbon nanotubes (MWCNTs) on the mechanical and thermal properties of curauá-fiber-reinforced composites. The MWCNTs were added either to the fiber surface or into the resin matrix as the second reinforcing phase. The MWCNT-modified curauá fibers as well as raw fibers were characterized using a single-fiber tensile test, TGA, and FTIR analysis. Further, different composite samples, namely, pure curauá, (curauá + MWCNTs) + resin and curauá+ (resin + MWCNTs), were manufactured via compression molding and tested to determine their mechanical and thermal properties. Scanning electron microscopy (SEM) analysis was used to examine the surfaces of the tested fibers. It was found that the addition of MWCNTs to the curauá fibers resulted in positive effects (an enhancement in properties was found for the MWCNT-modified fibers and their composites). The addition of MWCNTs also increased the thermal stability of the natural fibers and composites. [ABSTRACT FROM AUTHOR]

Highlights: A core-sheath structured coaxial composite fiber with highly aligned and densely stacked boron nitride nanosheets arrangements in the sheath was successfully fabricated. The coaxial fibers have an ultrahigh axial Herman orientation parameter of 0.81, thermal conductivity of 17.2 W m−1 K−1, and tensile strength of 192.5 MPa. The coaxial fibers exhibit intensively potential applications in the wearable thermal management textile. Hexagonal boron nitride nanosheets (BNNSs) exhibit remarkable thermal and dielectric properties. However, their self-assembly and alignment in macroscopic forms remain challenging due to the chemical inertness of boron nitride, thereby limiting their performance in applications such as thermal management. In this study, we present a coaxial wet spinning approach for the fabrication of BNNSs/polymer composite fibers with high nanosheet orientation. The composite fibers were prepared using a superacid-based solvent system and showed a layered structure comprising an aramid core and an aramid/BNNSs sheath. Notably, the coaxial fibers exhibited significantly higher BNNSs alignment compared to uniaxial aramid/BNNSs fibers, primarily due to the additional compressive forces exerted at the core-sheath interface during the hot drawing process. With a BNNSs loading of 60 wt%, the resulting coaxial fibers showed exceptional properties, including an ultrahigh Herman orientation parameter of 0.81, thermal conductivity of 17.2 W m−1 K−1, and tensile strength of 192.5 MPa. These results surpassed those of uniaxial fibers and previously reported BNNSs composite fibers, making them highly suitable for applications such as wearable thermal management textiles. Our findings present a promising strategy for fabricating high-performance composite fibers based on BNNSs. [ABSTRACT FROM AUTHOR]

The layered fibers of carbon-fiber-reinforced polymer (CFRP) composites exhibit low thermal conductivity (TC) throughout their thickness due to the poor TC of the polymeric resin. Improved heat transmission inside the hydrogen storage tank during the filling process can reduce further compression work, and improved heat insulation can minimize energy loss. Therefore, it is crucial to understand the thermal properties of composites. This paper reports the thermal behavior of plain-woven CFRP composite using simulation at the micro-, meso-, and macro-scales. The TC was predicted numerically and compared to experimental findings and analytical models. Good results were found. Using the approach of multi-scale modeling, a parametric study was carried out to analyze in depth the influence of certain variables on thermal properties. The study revealed that both fiber volume fraction and temperature significantly influenced the TC of the composite, with the interphase fiber/matrix thickness following closely in terms of impact. The matrix porosity was found to have a relatively slighter impact, particularly within the porosity range of 5 to 15%. [ABSTRACT FROM AUTHOR]

Semi‐crystalline poly (arylene ether nitrile) (PEN) with outstanding thermal stability and mechanical properties are expected to be used in structural materials. Increasing the crystallinity of PEN helps improve the processability of the materials as well as the thermal and mechanical properties of the products. In present work, the comprehensive properties of PEN composites are improved by the introduction of aramid staple fiber combined with hot stretching method. The effects of aramid fiber content and hot stretch multiplicity on the properties of the composite were investigated. The result shows that when the mass fraction of aramid fiber (AF) powder is 0.3% (PEN/AF3), the composites have the best overall performance, including thermal and mechanical properties. In addition, when the tensile ratio was 300% (PEN/AF3‐300), the properties of the samples are greatly improved, with the crystallinity increasing to 36.1%, the thermal decomposition temperature of 5% (Td5%) increasing by 10°C, and the tensile strength increasing to 195.40 MPa, which is 87.34% higher than that of the non‐thermal tensile composites. Therefore, this work provides a technical route for the preparation of high performance semi‐crystalline PEN composites, which is beneficial for the development of PEN applications. [ABSTRACT FROM AUTHOR]

In the high‐tech field, there is an urgent need for materials that possess thermal insulation, mechanical properties, and processing properties. One promising option is Carbon fiber reinforced thermoplastic composites (CFRTPs), which exhibit excellent characteristics such as light weight, high strength, and high temperature resistance. The effects and mechanisms of hollow glass beads (HGB) on the thermal insulation and mechanical properties of carbon fiber‐reinforced thermoplastic polyphthalazine ether sulfone ketone composites (CF/PPESK) were investigated. The introduction of 15 wt% HGB improved the material's thermal insulation performance by 32.74% perpendicular to the fiber direction and 44.95% parallel to the fiber direction. Furthermore, the addition of 3 wt% HGB increased the interlaminar shear strength, compression strength, and flexural strength by 21.34%, 17.49%, and 5.53%, respectively. Additionally, the dynamic mechanical analysis confirmed that the HGB/CF/PPESK composite has superior high‐temperature mechanical properties, which holds great promise for CFRTPs applications. Highlights: Modification of CF/PPESK with HGB improved its thermal insulation properties.Analysis of the mechanism of CF/PPESK for thermal insulation performance.HGB improved the mechanical properties by delaying the expansion of microcracks.Agglomeration of HGB leads to a rapid rise in thermal insulation properties. [ABSTRACT FROM AUTHOR]

Natural fiber reinforced polymer composites (NFRPCs) have emerged as promising eco‐friendly alternatives over conventional synthetic fiber composites due to their inherent biodegradability, renewability, low environmental impact, and lightweight properties. It has been seen a significant growth in both invention and innovation in the field of NFRPCs. Natural fibers (NFs) reduce the cost of the material by 5%, the weight of the composite by 10%, and the energy required for production by 80%. In terms of thermal, and acoustic properties, NFs can successfully compete with synthetic fibers. As a result, the development of NFRPCs for industrial use has increased significantly in the past decade to meet the growing demands of industrial sectors. To improve the thermal and acoustic properties of NFRPCs, researchers have done a lot of investigation. The aim of the current review is to provide a comprehensive analysis of the existing literature on the thermal and acoustic properties of natural fiber reinforced polymer composites. Thermal properties such as thermal conductivity, TGA, DSC, DMA, and acoustic properties of natural fiber reinforced composites with several parameters, such as different fiber types, different matrix types, fiber weight ratio, fiber to matrix ratio, chemical treatment of fiber have been summarized and analyzed very concisely. This review also emphasizes a summary of different natural fibers, their chemical compositions, composite preparation, characterizations, and future research directions. This article enables the readers, researchers, and manufacturers to realize several opportunities about the latest developments in NFRPCs for the application of thermal and acoustic purposes. Highlights: Natural fibers can successfully compete with synthetic fibers, in terms of thermal and acoustic properties.Thermal properties of natural fiber reinforced composites including thermal conductivity, TGA, DSC, and DMA are summarized.Acoustic properties of natural fiber reinforced polymer composites are discussed.Composite materials made of treated fibers result better thermal stability than untreated fiber composites.Sound absorption coefficient generally increases as fiber content increases. [ABSTRACT FROM AUTHOR]

Additive manufacturing of composite materials is a nascent technology that is being investigated for manufacturing optimized structural composite designs. By combining additive manufacturing of continuous fiber composites with topology optimization, fibers can be steered in the loading direction. Steered fibers allow for decreased weight, decreased manufacturing time, and reduced cost. Realizing the benefit of printed composites enables production of low cost unmanned vehicles at a higher rate with high specificity. Mechanical properties of printed composites, which are needed for design, are measured in this work. Composite properties were comparable to traditionally manufactured composites, especially when normalized by cured ply thickness. Transverse properties were limited by the brittleness of the photopolymer matrix. Matrix cure characteristics and thermal properties were also measured which revealed the high temperature capabilities of the matrix with a Tg of 198°C. [ABSTRACT FROM AUTHOR]

This work aimed to study the influence of the polybutylene succinate (PBS) content on the physical, thermal, mechanical, and chemical properties of the obtained polylactic acid (PLA)/PBS composite fibers. PLA/PBS blend fibers were prepared by a simple melt-blown process capable of yielding nanofibers. Morphological analysis revealed that the fiber size was irregular and discontinuous in length. Including PBS affected the fiber size distribution, and the fibers had a smoother surface with increased amounts of added PBS. Differential scanning calorimetry analysis (DSC) revealed that the crystallization temperature of the PLA sheet (105.8 °C) was decreased with increasing PBS addition levels down to 91.7 °C at 10 wt.% PBS. This suggests that the addition of PBS may affect PLA crystallization, which is consistent with the X-ray diffraction analysis that revealed that the crystallinity of PLA (19.2%) was increased with increasing PBS addition up to 28.1% at 10 wt% PBS. Moreover, adding PBS increased the tensile properties while the % elongation at break was significantly decreased. [ABSTRACT FROM AUTHOR]

Polymer matrix wave transparent composites are used in a variety of high-speed communication applications. One of the applications of these involves making protective enclosures for antennas of microwave towers, air vehicles, weather radars, and underwater communication devices. Material performance, structural, thermal, and mechanical degradation are matters of concern as advanced wireless communication needs robust materials for radomes that can withstand mechanical and thermal stresses. These polymer composite radomes are installed externally on antennas and are exposed directly to ambient as well as severe conditions. In this research, epoxy resin was reinforced with a small amount of quartz fibers to yield an improved composite radome material compared to a pure epoxy composite with better thermal and mechanical properties. FTIR spectra, SEM morphology, dielectric constant (Ɛr) and dielectric loss (δ), thermal degradation (weight loss), and mechanical properties were determined. Compared to pure epoxy, the lowest values of Ɛr and δ were 3.26 and 0.021 with 30 wt.% quartz fibers in the composite, while 40% less weight loss was observed which shows its better thermal stability. The mechanical characteristics encompassing tensile and bending strength were improved by 42.8% and 48.3%. In high-speed communication applications, compared to a pure epoxy composite, adding only a small quantity of quartz fiber can improve the composite material's dielectric performance, durability, and thermal and mechanical strength. [ABSTRACT FROM AUTHOR]

Although petroleum-based polymers require a long process to decompose in nature, they still have a wide range of uses. However, due to many important reasons such as the environmental pollution problem caused by these polymers, there is an increasing interest in biodegradable polymers. Poly(lactic acid) (PLA) is a biopolymer with comparable performance to conventional polymers. However, due to its poor tribological, mechanical and thermal properties, the usage area of PLA cannot expand and its use is limited to short-term material applications. In this study, it was aimed to contribute to the expansion of the usage area of PLA by improving its poor properties. For this purpose, efficiency of graphene nanoplatelet (GnP) and/or Joncryl® addition to carbon fiber (CF) reinforced PLA matrix composites to improve the composite performance by means of improved interface interaction fiber and matrix was investigated. Within this scope, effects the separately and/or simultaneously addition of CF, GnP and Joncryl® to PLA on properties were investigated by tensile test, adhesive wear test, DSC, TGA and SEM analyses. All results revealed that the composite composition prepared by simultaneously addition of 10, 0.5 and 2 wt.% CF, GnP and Joncryl®, respectively, to pure PLA performed the best in all tests and analyses. [ABSTRACT FROM AUTHOR]

Environment friendly polymer composites made of plant based natural fibers such as bamboo fiber, roselle fiber (RF), aloe vera fiber (AF) oil, or kenaf fiber are cardinal of the current world toward sustainability. They offer lower carbon footprint, higher biodegradability, higher specific strength, higher thermal, and acoustic characteristics. On the other hand, properties of synthetic glass fibers (GFs) such as high specific strength to weight ratio, great resistance during impact, and high durability extend their application perspective for various engineering materials. As such, in the present study, mechanical properties and thermal stability of hybrid laminate comprising of natural fiber (i.e., AF and RF) and synthetic fiber (i.e., GF) fabricated using hand layup process were investigated. Experimental findings reveal that sequencing of the fibers significantly affects properties of the composite. Introducing a layer of AF between RF increased the tensile strength by 30.2% respectively while hybrid laminates composed of three successive layers of RF exhibited 12.6% higher impact strength compared to hybrid laminate composed of AF. Besides, the thermal stability of hybrid laminates was higher (i.e., minimal weight loss of <6.1% when heated up to 800°) compared to neat polymer or laminates with single reinforcement. The enhanced thermal stability, mechanical properties, and tribological properties of the "greener" hybrid laminates can be employed in various structural or lightweight industrial applications. Highlights: Hybridization using natural fibers and synthetic fibers are attempted and investigated.Fiber sequencing significantly affects mechanical properties of the composite.Higher thermal stability of hybrid laminates, that is, minimal weight loss of <6.1% when heated up to 800°.Laminated composed of AF in between RF exhibited lowest frictional coefficient."Green" hybrid polymer laminate suitable for various structural and lightweight industrial applications is identified. [ABSTRACT FROM AUTHOR]

Polyetherimide (PEI) is a high‐performance material that maintains good properties at high temperature. Combining PEI with 3D printing is helpful to broaden the application of PEI, but the printed PEI parts have poor mechanical properties due to its interlayer porous structure. Herein, high thermal processing (cavity and platform temperature) is utilized to improve the bonding of PEI filaments during 3D printing. After optimizing, the mechanical properties of printed PEI parts can reach to the performance of injected PEI. Moreover, carbon fiber (CF) is used to further enhance the thermal and mechanical properties of PEI. The results show that the mechanical enhancement of short length CF (0.15 mm) is less effective than the longer CF (3 mm‐CF). After the CF oxidation treatment, the tensile strength of printed PEI is increased by nearly 6.07% compared to the untreated CF/PEI. The work provides a novel approach for developing 3D printed CF/PEI composites for the further application. [ABSTRACT FROM AUTHOR]

Abaca is a strong competitor among natural fibres for use as the reinforcement of polymer composites. Due to its high durability, considerable fibre length, flexibility and mechanical strength, abaca shows good potential as a renewable source of fibres for application in technological and industrial fields. Discussing the influence of various treatment strategies, such as alkali and silane, for the preparation of abaca-based composites results in the improvement of their properties over that of bare polymer materials and that of other synthetic fibres. The enhanced characteristics of abaca fibre reinforced composites are widely explored for a variety of applications in automotive and other industries. These include for example roping and woven fabrics, currency notes, cigarette filter papers, vacuum bags, tea bags, cellulose pulp for paper and packaging, and materials for automotive components, etc. In particular, the effective use of abaca fibre reinforced polymer composite in manufacturing external parts of cars, using therefore also thermoplastic matrices, has become popular. The gaps in research from the literature that show the scarcity of studies on topics such as simulation and designing of mechanical characteristics of abaca fibre composites constructed on polymer matrices, such as epoxy, polylactide, high density polyethylene, phenol formaldehyde and polyester are also highlighted. The results indicate that abaca is particularly flexible to be used in different sectors, in combination with various matrices, and in hybrid composites with various fibres. Further work would necessarily involve the larger consideration of abaca textiles with different areal weights in the production of composites, and a widespread introduction of abaca in datasets for the automated selection of natural fibres for composites reinforcement. [ABSTRACT FROM AUTHOR]

In this study, the effect of fiber orientation on the temperature history during the layup process is comprehensively investigated experimentally and numerically. Specimens with three different fiber orientations (i.e. [0°/0°/0°], [0°/45°/0°], and [0°/90°/0°]) are manufactured at two layup speeds and characterized for determining the degree of intimate contact and then calculating the thermal contact resistance. Then, an improved thermal model with thermal contact resistance is developed and validated to predict the temperature history accurately. The experimental results indicate that the degree of intimate contact decreases by increasing the difference in fiber orientation between the interfaces of successive plies, revealing a relationship between substrate fiber orientations and cooling rates. The effect of cooling rate on the degree of crystallinity is studied for all stacking configurations at two layup speeds and found that as the angle between the subsequent plies decreases, the cooling increases, leading to a drop in the degree of crystallinity. The outcomes of this study address the need for an improved thermal model approach for accurately predicting the thermal history of the manufactured composite by the laser-assisted fiber placement process. [ABSTRACT FROM AUTHOR]

The present study is an attempt to fabricate composite nanofiber mats from polystyrene (PS) loaded with exfoliated graphite nanosheets (EGNS) by using electrospinning technique. EGNS with different weight ratios of 3, 6, and 9 wt.% were added to PS (20 wt.%). The fiber diameter and morphology of the composite nanofiber mats were investigated by scanning electron microscopy (SEM). Results revealed that as EGNS concentration was increased, the average diameter of EGNS/PS electrospun nanofibers decreased. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to investigate the thermal properties. The tensile strengths and Young's modulus of the composites improve with the increasing EGNS concentrations compared to PS nanofiber, which indicates 84% and 88% augmentation, respectively at 6 wt.% of EGNS. Also, the addition of EGNS increased thermal stability of composite nanofiber mats. [ABSTRACT FROM AUTHOR]

The aim of present work summarizes the synergistic effect of basalt fiber on mechanical, thermal and morphological behavior of PP/bamboo composite. The basalt fibers were varied at four different levels 5, 10, 15 and 20 wt% which replaces the bamboo fiber at 40 wt% while keeping both the fibers content constant at 40 wt%. PP/bamboo composite and PP/bamboo/basalt hybrid composites were fabricated through melt compounding of PP (polypropylene), PP‐g‐MA (grafted maleic anhydride polypropylene), alkaline treated bamboo fiber and silane treated basalt fiber, followed by injection molding. The addition of silanized basalt fiber in PP/bamboo composite linearly increased the tensile and flexural related properties while the impact strength decreased with the increase in basalt fiber. Theoretical modeling for tensile strength and modulus indicate the positive hybrid effect of basalt fiber. Results obtained from differential scanning calorimetry (DSC) indicated that the crystallinity of the neat PP increased with the incorporation of both the bamboo and basalt fiber. The Thermal degradation results showed that the PP/bamboo composite degraded earlier while the hybrid composite at 5 wt% basalt fiber showed highest thermal stability as compared to neat PP. Dynamic mechanical analysis (DMA) results exhibited that the viscoelastic properties enhanced with the addition of bamboo and basalt fiber. Scanning electron microscopy (SEM) micrographs on the tensile fractured surface revealed random orientation and wetting of basalt and bamboo fibers in PP matrix. [ABSTRACT FROM AUTHOR]

This work deals with the thermal, mechanical and dynamic properties of hybrid composites reinforced with carbon fibers and aramid fibers, whose matrix is epoxy resin. In this study a series of hybrid fiber composite are prepared with carbon and aramid fibers as reinforcement. Thermal properties are obtained by thermal gravimetric analysis (TGA), Thermo-mechanical analysis (TMA) and hot plate analysis. Also mechanical properties are obtained by tensile and modal analysis tests. The experimental results are compared with the similar theoretical ones. Besides the effect of stacking sequence and hybrid ratio (adding the number of layers of carbon fibers), on the thermal and mechanical properties are investigated. The results show that by increasing the hybrid ratio although the weight of the sample is more, the thermal conductivity of the carbon fibers used is higher than that of the aramid fibers and this increase in thermal conductivity causes the heat to be transferred to the sample much faster and the temperature of the glass increases with the increase of the hybrid ratio. Due to the high stiffness of carbon fibers, adding it to the composite causes, the tensile modulus of the samples increases. By combining carbon fibers with aramid fibers, the toughness of carbon fibers can be increased and at the same time the brittle property of carbon fibers is removed due to the malleability of aramid fibers. It is concluded that aramid fiber has an effective role in improving failure strain due to its high toughness and malleability, while carbon fiber is very fragile. The lowest tensile strength occurs at the hybrid ratio of 29% with a value of 677.66 MPa. which is very close to the theoretical critical hybrid ratio. The results also show when the carbon fibers and aramid fibers are on the outer and the middle layers of the beam respectively, the frequency has a larger value because the aramid fibers have a very high impact resistance. [ABSTRACT FROM AUTHOR]

Durian is Malaysia's most popular seasonal fruit, but less than half of the durian fruit is consumed as food. Durian is a type of fruit with a high percentage of waste, which becomes an environmental problem when discarded into the landfill site. Therefore, it is important to utilise durian waste as a potential natural fibre-based composite reinforcement. Durian skin residue is recognised as one of the potential lignocellulosic materials to replace wood in the insulation board industry. The present study aims to develop a low-cost insulation board using durian skin residues as reinforcing materials. Single-layer mats were manually formed, followed by hot pressing using polymeric methane diphenyl diisocyanate (PMDI) resin. The effect of different percentages of PMDI resin (0, 6, 8 and 10%) on the board's physical, mechanical, morphological, and thermal properties was investigated. It was found that 6% PMDI resin is the optimised resin amount to produce PMDI/durian skin fibre composite, and the board with 6% PMDI has the maximum static bending due to enhanced cross-linking by the fibre. In terms of thermal stability and conductivity, the incorporation of 6% of PMDI is considered the best formulation based on the value achieved. The overall results indicated that this study addresses a low-cost innovation for commercial insulation boards as it utilises durian waste and a low dosage of PMDI for implementation in the building and construction industry. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is one of the most commercially used thermoplastics, while a significant amount of PP is used in the form of fibers. In this study, the effects of modification of the filler on the thermal and mechanical properties of composite polypropylene/wollastonite drawn fibers were investigated. In this direction, the surface modification of wollastonite with various organic acids, such as myristic, maleic, malonic glutaric, pimelic, and suberic acid, and the use of two solvents were studied. The surface-modified wollastonite particles were used to produce composite polypropylene drawn fibers. The modification efficiency was found to be slightly better when a non-polar solvent (carbon tetrachloride) was used instead of a polar one (ethanol). FTIR experiments showed that myristic, maleic, malonic, and pimelic acid can strongly interact with wollastonite's surface. However, the mechanical strength of the composite fibers was not increased compared to that of the neat PP fibers, suggesting inadequate interactions between PP and wollastonite particles. Furthermore, it was observed that the drawing process increased around 10% the crystallinity of all samples. Wollastonite modified with malonic acid acted as a nucleating agent for β-crystals. The onset decomposition temperature increased by 5–10 °C for all samples containing 2% wollastonite, either modified or not. The suggested modifications of wollastonite might be more suitable for less hydrophobic polymers. [ABSTRACT FROM AUTHOR]