Functional Composite Materials最新文献

This study evaluates the mechanical performance and fractured behavior of recycled bovine leather fiber (RBLF)/epoxy (ER) composites produced using industrial post-consumer leather waste as a sustainable reinforcement for epoxy. Composites containing 5–10 wt% RBLF were fabricated and their properties were compared with those of neat epoxy. The developed composites exhibited the following properties: tensile strengths ranging from 14.22 to 41.73 MPa, flexural strengths from 76.54 to 125.92 MPa, flexural moduli from 1.46 to 2.50 GPa, compressive strengths from 74.13 to 126.46 MPa, and compressive moduli from 2.67 to 4.03 GPa. These values compare favorably with those reported in the literature for conventional natural and synthetic fiber-reinforced composites, including jute/epoxy and flax/epoxy systems, which were tested under similar conditions. Water absorption increased from 0.85–1.34% after 24 hours to 1.18–4.33% after 384 hours, reaching an almost constant value after 96 hours. The composites were further characterized using several methods: Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and three-dimensional surface topography analysis. The FTIR spectra confirmed effective cross-linking within the leather fiber/epoxy composites, as evidenced by the characteristic absorption bands at 2923–2924, 2852–2854, and 1455–1460 cm^{− 1}, corresponding to CH/CH₂ stretching vibrations. In addition, EDX analysis revealed that chromium, nitrogen, sodium, phosphorus, aluminum, and silicon, which were detected in the raw leather, were no longer observed in the composites, indicating that the leather fibers were effectively encapsulated by the epoxy matrix. Overall, these results demonstrate that recycled bovine leather fiber/epoxy composites represent a promising lightweight material for weight-sensitive applications.

Layer-by-layer (LbL) assembly of polyelectrolytes is a universal method for controlling composite coatings. When combined with atomic force microscopy (AFM), it is useful strategy to analyze morphology. Optimisation of the LbL technique is bottlenecked by manual sample preparation, and there is also a lack of standardised analytical pipelines to convert characterisation data into machine-readable descriptors. We address both bottlenecks by combining a collaborative robotic dip-coating platform with an automated feature-extraction backend for AFM topography. The robotic arm handles the substrate (Si wafer), immerses it in polyelectrolyte solution, and prepares samples for AFM study without operator intervention. Resulting AFM scans are transferred into a reproducible pipeline that applies a logged preprocessing chain and computes twelve groups of physically interpretable descriptors per sample: ISO 25,178 areal roughness, height-distribution statistics, radial power spectrum with Hurst and fractal exponents, two-dimensional autocorrelation, local-patch minima/maxima distributions, persistent homology of patch point clouds, gliding-box lacunarity, and a recipe-derived block of layer composition, sequence k-grams and RDKit monomer descriptors. Every descriptor is stored with the originating method version and parameters, supporting idempotent recomputation and side-by-side methodological evolution. The pipeline was applied to polyethyleneimine (PEI)/polystyrene sulfonate (PSS) assemblies on Si substrates, and an unsupervised principal component projection of the scalar descriptors already separates samples by the number of deposited layers, demonstrating that the resulting feature vectors carry coating-state information at a level useful for downstream machine learning. This work establishes a traceable, data‑driven bridge from synthesis instructions to high‑dimensional surface descriptors, demonstrating for the first time an end‑to‑end pipeline where robotic LbL assembly, versioned AFM processing, and hybrid topological‑chemical feature extraction converge into a single machine‑learning‑ready dataset.

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This study focuses on the evaluation of the mechanical, thermal, gas barrier, and electrical properties of segmented polyester-based TPU coatings with a low loading of 2D- graphene nanofillers, namely graphene oxide (GO), reduced graphene oxide (RGO), and graphene nanoplatelets (GNP), respectively. TPUs have a unique segmented structure featuring soft and hard segment alternation, which contributes to their inherent tailor-made flexibility and strength. Incorporation of the graphene fillers enhanced the thermal stability, mechanical performance, and electrical conductivity by virtue of their large surface area. TPU at 0.5 wt% GO displayed a tensile strength of 30.4 MPa and 800% elongation at break while preserving flexibility. GO and RGO decreased oxygen permeability by approximately 70% and 46%, respectively. RGO exhibited enhanced mechanical and electrical properties attributed to reduced oxygen content and increased π–π interactions. At 1.0 wt%, GNP established a percolated conductive network exhibiting an electrical conductivity of approximately 9.0 × 10^− 5 S/m, which is 66% greater than that of RGO filled composites. The various oxidation levels and morphologies of these fillers provide unique benefits, facilitating multifunctional TPU nanocomposites. This study clarifies the interactions between graphene and TPU, contributing to applications such as flexible electronics, packaging, protective coatings, and lighter-than-air vehicles.

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Styrene–butadiene rubber (SBR) is widely employed in applications requiring a balance of mechanical strength, processability, and wear resistance, such as vehicle track pads. However, conventional fillers such as carbon black and silica present limitations in simultaneously enhancing multiple performance attributes. In this study, graphene nanoplatelets were incorporated at low loadings (0.1, 0.3, and 0.5 phr) into SBR to evaluate their effect on vulcanization behavior, thermal stability, hardness, and wear resistance. Graphene incorporation increased the crosslink density of SBR by up to 17% but did not significantly affect curing kinetics, with all formulations showing an optimum cure time of approximately 18 min. Thermal analysis revealed no significant changes in the main degradation pathways of SBR, although the increase in glass transition temperature suggests restricted chain mobility. Shore D hardness increased with increasing graphene content, rising from 31 at 0 phr to 33.4 at 0.5 phr, confirming the reinforcing effect of graphene nanoplatelets at low concentrations. Wear performance, evaluated by both mass-loss and volume-loss abrasion tests, demonstrated a clear reduction in wear with increasing graphene content. The best performance was observed for 0.5 phr graphene, where mass loss decreased up to 26% compared to neat SBR. These results contrast with previous studies that reported deterioration in abrasion resistance at higher graphene loadings, supporting the hypothesis that graphene acts as a reinforcing filler only at low concentrations. Overall, the findings highlight the potential of graphene nanoplatelets to improve hardness and abrasion resistance in SBR without compromising curing or thermal stability.

AgI-MCM48-ZnI₂ hybrid powders (HPs) based on mesoporous silica and silver/zinc iodides were synthesized via the hydrothermal template co-condensation (HTC) method. Particular attention was paid to the post-synthetic treatment, specifically the annealing stage. The primary objective was to determine the optimal annealing temperature that enables the full development of the composite’s structural and textural properties while preserving the metal iodide crystals. The physicochemical characteristics of the HPs were evaluated using various analytical methods, with the retention of AgI and ZnI₂ phases, specific surface area, and pore parameters serving as key control indicators.The results confirm that the morphology of the AgI-MCM48-ZnI₂ HPs is governed by the structural features of the unmodified MCM-48 matrix. It was demonstrated that reducing the annealing temperature to 550 °C allows for a 25 wt% increase in the zinc iodide content within the HPs while effectively preventing the formation of undesired zinc oxide. Furthermore, this optimized temperature regime contributed to a 1.5–2.0-fold increase in both specific surface area and pore diameter. The incorporation of zinc iodide was shown to significantly enhance the thermal stability of silver iodide. These findings suggest that the synthesized AgI-MCM48-ZnI₂ composites are highly promising for weather modification technologies, specifically for hail suppression and rainfall enhancement.

In recent years, the development of hydrophobic, UV-resistant, and self-healable polymer/metal organic framework (MOF) composites has attracted considerable scientific interest for advanced coating applications. In this study, a copolymer of glycidyl methacrylate and lauryl methacrylate, P(GMA-co-LMA) (PGL), was synthesized to impart hydrophobicity, mechanical flexibility, and heat-induced self-healing behaviour, while a Ti-based MOF was incorporated to introduce antimicrobial activity and UV-blocking functionality. The resulting polymer-containing MOF (PcMOF) composite demonstrated significantly enhanced multifunctional performance. Notably, the PcMOF exhibited a high water contact angle (WCA) of approximately 120°, indicating strong hydrophobicity, along with nearly zero UV transmittance, confirming excellent UV-shielding capability. Comprehensive characterization of the PcMOF composites was carried out using FTIR, scanning electron microscopy (SEM), UV-Vis spectroscopy, WCA measurements, and antibacterial assays. The PcMOF coating was successfully applied to both cotton fabric and glass substrates, demonstrating effective self-cleaning behaviour, UV resistance, and antibacterial activity. Owing to its combined hydrophobic, UV-protective, self-healing, and antimicrobial properties, the developed PcMOF composite shows potential for high-performance multifunctional coatings.

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The sustainable development of high-performance materials from renewable resources has gained substantial attention in recent years. In this study, biochar was synthesized from agricultural waste i.e. bamboo waste (WBB) via a green route and subsequently functionalized with ammonium persulfate (APS) to improve dispersion and interfacial bonding. The functionalized bamboo waste biochar was incorporated into a polyvinyl alcohol (PVA) matrix to fabricate nanocomposites with enhanced structural properties. Comprehensive characterization was carried out using FTIR, XRD, FE-SEM, XPS, and Raman spectroscopy to confirm successful functionalization and uniform distribution of WBB within the PVA matrix. Mechanical testing revealed significant improvements in tensile strength, Young’s modulus, and toughness, demonstrating the reinforcing effect of APS-functionalized waste bamboo biochar (WBFB). Thermal stability analysis confirmed enhanced resistance to degradation, further validating the material’s suitability for engineering applications. The results revealed that the incorporation of WBFB significantly enhanced the performance of PVA. At an optimal biochar loading of 5 wt%, tensile strength increased by approximately 62.43% compared to pure PVA and Young’s modulus increased from 3088 MPa (pure PVA) to 7496 MPa, respectively. Thermal stability also increased from 325.70 °C (T_50%) for pure PVA to 384.81 °C (T_50%) for the 5% biochar functionalized composite. DSC analysis revealed enhancement in the thermal characteristics T_m and T_c by 8.79 °C and 13.02 °C at an optimal biochar loading of 5 wt%. The synergistic combination of bamboo waste derived biochar and PVA establishes a cost-effective, eco-friendly, and mechanically robust nanocomposite with strong potential for use in advanced structural and sustainable material applications.

Over the past few decades, thermoset-based fibrous composites have proven to be a superior alternative to metals in structural applications. Thermosets, especially epoxy-based FRP composites, have widespread acceptance due to their ease in fabrication along with excellent strength-to-weight ratio, chemical resistance, and minimal environmental impact. However, in the era of sustainability, extensive application of thermoset-based FRP composites is limited due to their poor recyclability, which poses an environmental threat. To address this issue, thermoplastic matrix-based composites present a promising alternative. Typically, thermoplastic matrices are available in pellet or sheet form, requiring high temperature processing which complicates the fabrication process. To overcome these challenges, a new liquid, Methyl Methacrylate (MMA)-based Liquid Thermoplastic Resin (LTR), has recently been developed. This study systematically evaluates LTR based glass fibre composite (GF/LTR) in various mechanical properties, including flexural strength, interlaminar fracture toughness, and interlaminar shear strength at different temperatures, and compares it with conventional epoxy based glass fibre composite (GF/Epoxy). The VARTM process was used to fabricate both the composites. In every assessment, GF/LTR outperformed GF/Epoxy composites, such as in flexural test at 30℃ GF/LTR composite exhibited 18% higher performance compared to the GF/Epoxy composites. Also, the fracture toughness of GF/LTR shows an improvement of approximately 27.5% at 30℃ and 36.5% at 50 °C, over GF/Epoxy, highlighting the superior fibre-matrix interaction and cohesive integrity in composite LTR. Additionally, fractographic analysis was conducted to gain insights into the failure modes of GF/LTR composites.

The global transition toward low-carbon energy systems necessitates the development of materials that combine high performance with reduced environmental impact. Composite materials have emerged as critical enablers across energy generation, storage, transport, and infrastructure due to their superior strength-to-weight ratio, corrosion resistance, durability, and functional tailorability. This review provides a comprehensive assessment of polymer-, metal-, and ceramic-matrix composites, including advanced fiber and nanomaterial reinforcements, highlighting their structure–property relationships and manufacturing technologies. Advancement in the lightweight blade structures, recyclable matrixes, high temperature ceramic matrix composite and multi-functional composite for thermal and electrical management were highlighted. Sector-specific applications in oil and gas, hydrogen energy, renewables, and nuclear systems are discussed, emphasizing the role of composites in decarbonization, efficiency enhancement, and lifecycle emission reduction.

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Schematic representation of composite materials application for various energy system: linking structure property relation to decarbonization

This paper proposes a novel method for preparing a flexible strain sensor based on a PDMS (Polydimethylsiloxane)/MXene/Single-walled carbon nanotube (SWCNT) nanocomposite. MXene (Ti₃C₂T_x) was synthesized using a modified MILD method from the MAX phase, which demonstrated improved exfoliation compared to the other method. The polymer nanocomposite was fabricated using the solvent casting technique. The effective intercalation of SWCNTs within MXene layers significantly enhances the electrical conductivity of the nanocomposite. The flexible strain sensor was successfully fabricated and exhibited a wide strain detection range exceeding 50%. The flexible strain sensor was evaluated through multiple tests, including a 60-minutes stretch and release cycle, torsion tests, finger bending, and wrist motion detection, demonstrating its potential application in human motion monitoring. Strain sensing performances, including stretchability, linearity, and durability, were comprehensively evaluated, and compared for PDMS/SWCNT and PDMS/MXene/SWCNT film. In addition, differential scanning calorimetry (DSC) tests were performed to evaluate thermal properties.