The addition of nanofiller particles to a polymer matrix has long been known to enhance or modify the composite's mechanical and rheological properties. However, quantitatively capturing such changes with molecular level simulations remains computationally challenging. Toward that goal, we performed coarse-grained molecular dynamics of a nanocomposite system at a fixed (25 vol %) filler loading under nonspecific, weak polymer-filler interactions representative of a broad class of technologically important materials. We report several interesting results, including: (1) the equilibrium chain-configuration remains Gaussian-like as in an unfilled melt; (2) smaller filler particles display a stronger tendency to cluster; (3) larger fillers act as plasticizers by reducing the entanglement density and accelerating the chain mobility; and (4) fillers enhance the tensile response modulus, with the effect being stronger for larger particles. We also simulate cluster breakup, yielding, and elongational flow under an applied time-linear tensile strain and study the flow viscosity as a function of filler-size and chain-length.

From classical machine learning to modern neural networks for multi-output prediction of metallic composites mechanical properties using a small molecular dynamics-driven dataset: Application to Al–Cu alloys with pre-existing voids

ABSTRACT To enhance the flame retardancy of epoxy resin (EP), aluminum diethyl phosphinate (ADP) was surface‐modified using phenyl trimethoxysilane (PTMS). The modified ADP (PTMS@ADP) was then used as a main flame retardant, in combination with melamine polyphosphate (MPP) as a synergistic acid source and triazine carbonization agent (CFA) as a carbon source, to fabricate an intumescent flame retardant system (PTMS@ADP/MPP/CFA), hereafter referred to as IFR system. This system was incorporated into EP materials to investigate the flame retardancy of the resulting composites. The synergistic flame‐retardant effects among PTMS@ADP, MPP, and CFA were analyzed using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and char residue analysis. The results show that the carbon residue rate of PTMS@ADP after modification is increased to 37.4 wt %, which is 63.3% higher than that of ADP, showing higher thermal stability at high temperature. Under a constant total loading of 15 wt %, the optimal ratio of PTMS@ADP:MPP:CFA was found to be 3:2:1, achieving the highest LOI value of 33.5%, with all samples meeting the V‐0 rating. Additionally, the char yield at 600°C increased by 89.6% compared with pure EP. Cone calorimetry tests revealed that the average heat release rate and total smoke production were reduced by 40.7% and 29.7%, respectively, indicating that the IFR system significantly improved both the flame retardancy and smoke suppression of the EP composites. The mechanical properties of the EP composite were significantly reduced when ADP was added alone. In contrast, the mechanical properties of the composite were improved upon the addition of PTMS@ADP or PTMS@ADP/MCA/CFA, although they remained lower than those of pure EP. Based on the comprehensive test results of flame retardancy and mechanical properties, the PTMS@ADP/MCA/CFA composite is suitable for applications requiring high flame retardancy with relatively lower demands on mechanical performance.

The prevalence of mechanical structures in industrial sectors has increased thanks to 3D printing technology. This technology requires fewer mechanical bonds to assemble structures, but challenges arise due to material differences and cost. One impactful approach to enhancing mechanical characteristics is to design sandwich structures. This study used ASA and ABS to produce a sandwich composite, exploiting each material's positive attributes. The mechanical properties of the composite sandwich plates were investigated to assess their use as structural parts. The outer parts of the sandwich structure are made of ASA material resistant to external factors and the inner part is made of ABS material with flexural strength. Layer thickness was utilised as a variable printing parameter. In the present study, tensile and flexural tests were conducted, with the objective of comparing the mechanical characteristics of components fabricated from pure ASA and ABS materials, and from sandwich composite parts. The findings of the study demonstrated that the maximum tensile strength of 33.18 MPa and the maximum flexural strength of 57.78 MPa were observed in the sandwich samples produced with an ASA/ABS/ASA layer thickness of 0.15 mm. The study is of significance to industries such as automotive and aviation, insofar as it explores the potential areas of use for functional sandwich structures produced from different materials and increases their use.

Machine learning holds a great promise for applications in the experimental characterization of the mechanical properties of composites. However, conventional neural networks often suffer from low training efficiency, limited predictive accuracy, and strong dependence on the amount and quality of experimental data. In this paper, we propose a generalizable framework, referred to as a dimensional analysis-guided neural network (DANN), by integrating dimensional analysis with the neural network architecture. Through the introduction of a dimensionless transformation layer, DANN converts both the inputs and outputs into dimensionless groups, thereby embedding the principle of physical similarity into the learning process. The framework is validated via an inverse indentation problem involving fiber-reinforced composites. In comparison with conventional neural networks, DANN demonstrates higher accuracy, improved data efficiency, and greater robustness. Thus, DANN provides a physics-informed, data-efficient, and scalable approach for addressing complex problems in solid mechanics.

Abstract Unsaturated polyester resin is the most versatile polymer with wide range of application but it has low impact strength, low elongation at break and low toughness. Its mechanical and microstructural properties can be enhanced by the addition of optimum amount of Nanocellulose, nanosilica fillers and latex liquid rubber. Mechanical and microstructural properties characterization of the composite material (resin, latex rubber and nanocellulose) has been tested for 0.5 %, 1 %, 3 %, & 5 % by weight of the latex liquid rubber as fiber weight fraction. The characterization has been done for tensile, compression, impact, bending, XRD (X-ray powder Diffraction method), FTIR (Fourier Transform Infrared Spectroscopy) and flexural test. The aim is to obtain modified polyester resin nano composite material with enhanced mechanical properties of strength and toughness for industrial and structural application such as packaging, composite matrix for improved vehicle bumper application, water tanker construction, adhesive application and biomedical industries. The composite material mechanical properties has been enhanced about 40 % for the tensile strength, 35 % for flexural, 65 % for compression strength and 10 % for impact strength up on the addition of 2 % nano cellulose with diameter of 10 nm as particle size and 3 % by weight liquid rubber polymer.

Research on Nano-Zinc Oxide Modifying Crosslinked Polyethylene Composites Crystallinity, Electrical and Mechanical Properties

Composites with a multiscale distribution of pores are widely seen in nature and engineering. With the given total pore volume fraction, what is the influence of pore distribution pattern across scales on the effective mechanical properties of composites remains unexplored. Therefore, we develop a computational model to quantitatively study the cross-scale pore distribution effects on composites. A two-scale progressive damage method is proposed to capture the elastic and strength properties of composites with hierarchical microstructures, where the fibers embedded in matrix at different scales are modeled by imposing periodic boundary conditions on repeating unit cells (RUC). A recursive algorithm is proposed where the homogenized moduli and strength of lower scale microstructures are employed for the prediction of upper scales with fixed total pore volume fraction across two scales. The effectiveness of the model is verified by comparing the results with Chamis model. Parametric studies have been conducted for two kinds of composites, namely carbon-fiber and glass-fiber composites, showing that the optimized strength of composites may be achieved by the proper distribution of pore defects across scales. This work provides an efficient algorithm for studying pore defects redistribution effects across scales on effective moduli and strength of composites with hierarchical microstructures.

The valorisation of natural waste proves highly promising given its abundance in our environment. In this context, we developed a polyester matrix composite reinforced with treated fibres extracted from the coconut rachis (Cocos nucifera). Prior to incorporation, the fibres were subjected to an alkaline treatment and then added at different volume fractions (10%, 15%, 20%, 25%, and 30%) into the matrix using a manual hand lay-up technique. After fabrication of the composite material, the physical, mechanical, and thermal properties of each specimen were evaluated. Regarding the physical properties, the results indicate an increase in composite porosity, ranging from 6.877% to 13.437% depending on the fibre content. The water absorption rate shows a slight, monotonic rise, averaging 0.49%. Concerning the mechanical properties, the composite containing 25% fibres exhibits the best tensile and flexural strengths, with values of 19.450 MPa and 28.718 MPa, respectively. Thermal assessment using an asymmetric hot plate device reveals that fibre incorporation enhances the thermal insulation of the material. Furthermore, X-ray diffraction (XRD) analysis highlights a predominantly amorphous structure at 0% fibre content, with characteristic peaks of polyester. From 15% onwards, crystallinity peaks associated with cellulose and minerals begin to appear. At 25% and 30%, crystallinity becomes more pronounced, reflecting improved structuring of the fibrous phases and stronger interaction with the matrix. These observations are consistent with the literature on natural fibre composites.

Low-viscosity epoxy-containing diluents are used to reduce the initial viscosity of highly filled, wear-resistant epoxy systems and to improve filler wetting and dispersion. This study determined physical parameters by an atomic-increment approach and electronic descriptors using the Parametric Method 3 (PM3) semi-empirical method. Clear relationships were established between the effective molar cohesion energy and the solubility parameter with van der Waals volume. Linear dependencies were also obtained between the diluent surface tension and spreading coefficients on model high-hardness fillers, including silicon carbide, boron carbide, and normal corundum. The activity of epoxy diluents depends on the lowest unoccupied molecular orbital energy. These diluents influence processing and the final physical and mechanical properties of composites, making their selection critical for strength, hardness, and wear resistance. Computational analysis enables prediction of diluent behavior, reducing experimental time and cost. Integrating physical and quantum-chemical data into epoxy diluent design accelerates the search for optimal components and improves production of durable, high-performance epoxy composites.

Magnetic soft manganese–zinc ferrite in a concentration scale ranging from 100 to 500 phr was incorporated into acrylonitrile-butadiene rubber. The work was focused on the investigation of manganese–zinc ferrite content on electromagnetic interference shielding effectiveness and mechanical properties of composites. The rubber-based products used in industrial practice should not only provide good utility and functional properties but should also exhibit good stability towards degradation factors, like oxygen and ozone. Therefore, the samples were exposed to the thermo-oxidative and ozone ageing conditions, and the influence of both factors on the composites’ properties was evaluated. The results demonstrated that the incorporation of ferrite into the rubber matrix resulted in the fabrication of composites with absorption-shielding performance. It was demonstrated that the higher the ferrite content, the lower the absorption-shielding ability. Electrical and thermal conductivity showed an increasing trend with increasing content of ferrite. On the other hand, the study of mechanical properties implied that ferrite acts as a non-reinforcing filler, leading to a decrease in tensile characteristics. Thermo-oxidative ageing tests revealed that ferrite, mainly in high amounts, could accelerate the degradation processes in composites. Though the absorption-shielding performance of composites after ageing corresponded to that of their equivalents before ageing, it can also be concluded that the higher the amount of ferrite in the rubber matrix, the lower the composites’ stability against ozone ageing.

Different combinations of matrices and reinforcements in composites make the study of this class of materials a challenge, especially when pultrusion is the manufacturing process employed. Pultrusion is well documented in the literature and offers numerous applications across various sectors, including automotive, construction, aerospace, and furniture industries, among others. In this study, glass fiber-reinforced resin composites were produced via pultrusion, varying between unsaturated polyester (UP) and vinyl ester (VE) resins, and glass fibers in the forms of filaments, woven fabric (WF), and mat (MAT). The composites morphological properties (SEM), physical properties (density and void content), dynamic-mechanical properties (DMA), and mechanical properties (tensile and impact strength) were evaluated. Considering the properties assessed, composites with vinyl ester resin exhibited similar density, higher glass transition temperature, greater storage and loss moduli by DMA, improved matrix/reinforcement adhesion as observed by SEM, higher tensile and impact strengths, and lower void content compared to those with unsaturated polyester resin. Regarding the reinforcement type, the mat presented superior thermal, morphological, and impact resistance properties, whereas the woven fabric demonstrated lower void content and higher tensile strength than the mat. Ultimately, the best results among the produced composites were obtained with the VE/MAT and VE/WF samples.

Comprehensive Summary Understanding the interfacial interactions between covalent organic frameworks (COFs) and polymer matrices remains a critical challenge for the development of high‐performance mixed matrix membranes (MMMs) for gas separation and mechanical robustness. Here, we systematically study MMMs made of highly crystalline and monodispersed 2D PDA‐HTA COF and 3D‐Py‐COF with commonly used PIM‐1 and 6FDA‐DAM as matrix. A comprehensive gas permeation, electron microscopy and mechanical properties analysis revealed that the incorporation of these porous fillers universally decreased gas permeability, which is mainly due to polymer chain infiltration. The large pores of the 2D COF promote deep polymer penetration, leading to pore blockage and the formation of a rigidified, selective interfacial region. In contrast, the small pores of the 3D COF largely prevent infiltration, resulting in a more classic, weakly‐adhered filler. Crucially, this same infiltration mechanism dictates the composite's mechanical properties, inducing complex plasticization and reinforcement phenomena that are highly dependent on the specific COF‐polymer pairing. These findings offer mechanistic insights and design principles for optimizing the interface in MMMs, paving the way for advanced membranes with both excellent separation and mechanical performance.

ABSTRACT Frictional wear between fiber bundles during the braiding process is a key factor leading to the degradation of the mechanical properties of composites. To investigate the mechanism of regulating the friction behavior between yarns during the braiding process of preforms, a multi‐parameter controllable yarn friction test platform was constructed to systematically investigate the mechanisms of the influence of friction rate, normal force, preloaded tension, friction angle, and fiber type on the friction characteristics of yarns. The experimental results show that the dynamic friction coefficient between fiber bundles varies only 2.5% within the rate range of 2.5–10 mm/s, which shows excellent rate stability. The increase of normal force leads to a power‐law decrease in the friction coefficient, which is especially significant when the friction angle is smaller. This is consistent with the theory of Howell's friction model. The decrease of the friction angle leads to the approximate linear increase of the friction coefficient. The pre‐tension force is positively correlated with the contact area between fiber bundles and the friction coefficient. The study indicates the nonlinear evolution of yarn friction behavior under various influencing factors, providing important theoretical and methodological support for optimizing process parameters and achieving high‐quality, low‐damage forming of high‐performance braided precursors.

A 3D printing filament was fabricated from poly(lactic acid) (PLA), cassava pulp (CP), and epoxy using a twin-screw extruder. Several bio-composites were synthesized by varying the amount of epoxy (0.5, 1.0, 3.0, 5.0, and 10.0 wt.%). The size of the CP fibers significantly affected the surface quality, filament diameter, and mechanical properties of the final product. The smallest fiber size (45 µm) provided a smooth surface and consistent diameter. Incorporating 1 wt.% of epoxy into PLA/CP enhanced the tensile strength (56.6 MPa), elongation at break (6.2%), and hydrophobicity of the composite. The composite mechanical properties deteriorated at epoxy contents above 1 wt.% due to the amplified plasticizer effect of excessive epoxy. The optimized PLA/CP/epoxy formulation was used to generate the 3D filament. The resultant filament displayed a tensile strength of 64.6 MPa and elongation at break of 9.8%, attributed to the fine morphology achieved via thorough mixing provided by the twin-screw extruder. Epoxide-mediated crosslinking between PLA and CP enabled the development of a novel 3D printing filament with excellent mechanical properties. This research illustrates how agricultural residues can be upcycled into high-performance biomaterials with innovation in sustainable manufacturing, inclusive economic growth, reducing reliance on petroleum-based plastics and thus providing benefits regarding human health, climate change mitigation, plastic in the ocean, and environmental impacts.

Magnesium composites remain highly relevant for biodegradable implant applications due to their biocompatibility and properties such as density and elastic modulus, which closely resemble those of human cortical bone. However, magnesium's high corrosion susceptibility in aqueous environments, such as those found in the human body, poses a significant challenge for its use in biomedical applications. Additionally, orthopedic implants require adequate load‐bearing capacity. To address these issues, this study fabricated a hybrid nanocomposite using a magnesium‐2.5 wt. % zinc matrix, reinforced with reduced graphene oxide and hydroxyapatite nanoparticles, through vacuum‐assisted stir casting. The composite's mechanical properties and wear resistance were evaluated through tribological analysis, while its corrosion behavior in simulated body fluid was assessed to determine its suitability for use as biodegradable orthopedic implants.

The increasing demand for lightweight, high-performance materials has driven the development of textile-reinforced composites with integrated sensing capabilities. While thermoset-based composites have established sensor integration strategies, thermoplastic composites face challenges due to high processing temperatures. This study presents a novel approach to produce high-temperature-resistant, electrically conductive polyether ether ketone with multi-walled carbon nanotubes (PEEK/MWCNT) monofilament and core-sheath (PEEK-MWCNT/PEEK) filament yarns suitable for textile processing and structural health monitoring. Filaments were produced using a twin-screw extrusion site and a bicomponent melt spinning plant, systematically varying MWCNT content (1.0–7.0 wt.%) and process parameters. Differential scanning calorimetry revealed that MWCNTs influence PEEK crystallinity, glass transition temperature, and thermal transitions, while scanning electron microscopy (SEM) images confirmed filler dispersion and morphology. Mechanical testing demonstrated increased stiffness and tensile strength with higher MWCNT loading, while elongation at break decreased. Integration of conductive filaments into glass fiber/polypropylene (GF/PP) composites maintained or slightly improved composite mechanical properties. Electrical contacting via crimping combined with conductive epoxy provided stable, low-resistance connections. The results demonstrate that PEEK/MWCNT sensor yarns are suitable for high-temperature, textile-reinforced thermoplastic composites, offering a robust platform for intrinsically conductive, processable, and mechanically stable structural health monitoring systems.

The continuous rise in textile waste, driven by global population growth and the proliferation of fast fashion, has raised concerns about its efficient recycling and sustainable management. This study aims to assess the feasibility of recycling textile waste by incorporating recycled cotton fibres as reinforcement in polypropylene-based composites. Specifically, it examines the mechanical, thermal, and chemical properties of composites composed of 50% recycled polypropylene and 50% reinforcing fibres (either virgin or recycled cotton), with and without the addition of 5% maleic anhydride-grafted polypropylene as a compatibilizer to enhance fibre-matrix adhesion. Although the use of recycled cotton as reinforcement reduced the mechanical properties of the composite material, the addition of 5% compatibilizer improved these properties to levels comparable to those of composite reinforced with virgin cotton.

This study presents the results of numerical and experimental investigations into the impact of uneven fiber distribution in fiber-reinforced composites. A voxel-based model was developed using a Gaussian distribution with deviations of 5%, 10%, and 15% from an ideal hexagonal structure. Numerical simulations assessed the effect of microstructural statistical deviations on the elastic properties of composites. Computer vision methods were applied to analyze micrographs of real samples, enabling a comparison between modeled and actual material structures. The results demonstrated a significant influence of fiber misalignment on local stress concentrations and mechanical properties, validated by quantitative image analysis. This approach enhances the accuracy of predicting composite behavior under varying microstructural conditions.

This study aims to analyze the mechanical strength of composites with bamboo fiber and glass powder reinforcement using an epoxy matrix. The study used a hand lay-up method with three variations of volume fraction composition, namely (1) 15% bamboo fiber, 15% glass powder, 70% resin, (2) 20% bamboo fiber, 10% glass powder, 70% resin, and (3) 25% bamboo fiber, 5% glass powder, 70% resin. The bamboo fiber used was the result of alkali treatment using 15% NaOH solution to remove lignin and cellulose, while the glass powder was obtained from household glass waste with a particle size of 60 mesh. Mechanical property testing included tensile testing (ASTM D638 Type 1), compression testing (ASTM D695-96), and impact testing (ASTM D256), while morphological structure analysis was carried out using Scanning Electron Microscope (SEM) testing. The results showed that the volume fraction composition of 25:5:70 produced the highest tensile strength with an average value of 95.69 N/mm² and the highest impact strength of 29.91 J/mm. Meanwhile, the composition of 15:15:70 obtained the highest compressive strength of 57.13 MPa. SEM analysis of the composite fracture showed the occurrence of full out fiber, debonding, and void phenomena in the matrix, which affected the decrease in the material strength value. This indicates that variations in the composition of bamboo fiber and glass powder can optimize the mechanical properties of composites, while supporting the utilization of natural materials and waste as environmentally friendly innovation materials for automotive applications, especially Yamaha Vixion motorcycle visor products.