Balancing interfacial shear transfer and damage-tolerant energy dissipation remains a key challenge in high-performance aramid/epoxy composites. In this study, a multiscale interphase engineering strategy was developed by combining polydopamine (PDA)- or polydopamine/poly(ethyleneimine) (PDA–PEI)-modified aramid fibers with carbon nanotube/graphene oxide hybrid fillers in an epoxy matrix. Surface characterization, impact testing, interlaminar shear evaluation, dynamic mechanical analysis, and fracture observations were employed to elucidate how the interphase chemistry and hybrid filler architecture govern the load transfer and failure behavior. The incorporation of hybrid fillers into the neat epoxy matrix alone resulted in a limited performance improvement, whereas their integration within the fiber/interphase architecture led to significantly enhanced composite properties. The PDA-based hybrid system exhibited the most balanced combination of impact resistance, viscoelastic stiffness, and fracture energy dissipation, indicating the formation of an optimized interphase that enabled both efficient load transfer and controlled energy dissipation. In contrast, the PDA–PEI-based interphase exhibited reduced interlaminar shear strength and impact performance despite the increased density of the interfacial functional groups, suggesting the formation of a relatively dense and constrained interphase that limited effective stress transfer and damage tolerance. These results demonstrate that the composite performance is governed by not only increasing interfacial functionalization but also controlling the interplay among interfacial rigidity, molecular mobility, and damage evolution. This study provides a practical interphase design strategy for tailoring the balance between the impact resistance and shear performance in advanced aramid/epoxy composites.

This study explores the templating role of organic nanocrystals, specifically 2,9-dimethylquinacridone (PR), in enhancing the mechanical performance of polyacrylonitrile (PAN)-derived carbon fibers. By incorporating PR—structurally analogous to the acridone units formed during PAN stabilization—into the PAN matrix, we investigate how these nanofillers direct the crystalline evolution and reinforce the resulting carbon fibers. PAN/PR nanocomposite fibers were prepared by dry-jet wet spinning, followed by stabilization and carbonization. Microstructural analysis reveals that well-dispersed PR nanocrystals serve as efficient nucleation sites, catalyzing the development of ordered carbon crystalline domains during heat treatment. As a result, carbon fibers containing 1 wt% PR displayed a pronounced increase in tensile strength and modulus (16% and 13% higher, respectively, than control samples), attributed to optimal PAN-PR interaction and effective templating effects. These findings demonstrate that the templating behavior of organic crystalline nanofillers can be harnessed to simultaneously promote carbon crystal growth and reinforce mechanical properties in PAN-based carbon fibers. Our results highlight an efficient approach to nanofiller incorporation, establishing 2,9-dimethylquinacridone as a promising, non-polymeric reinforcement for next-generation high-performance carbon fibers.

To protect important organs, especially the chest, back, and abdomen from bullets and explosive pieces, military personnel, law enforcement agents, and security forces frequently use bulletproof vests as essential personal protection equipment. Kevlar is unique among materials designed for ballistic protection because of its exceptional impact resistance, low density, and exceptional tensile strength. Usually made up of several unidirectional layers of Kevlar fiber, soft body armor effectively absorbs and disperses the kinetic energy of approaching bullets. But Kevlar by itself cannot withstand armor-piercing gunfire or high-velocity rifle rounds, thus extra stiff materials must be added for improved protection. Kevlar fiber-reinforced epoxy (KRE) composites have become a highly effective material for next-generation body armor systems in order to overcome these constraints. A composite that bridges the gap between soft and hard armor is created by combining the strength and flexibility of Kevlar with the rigidity and structural integrity of epoxy resin. These materials are perfect for lightweight yet long-lasting defensive applications because of their exceptional mechanical strength, thermal stability, and energy absorption capability. Recent innovations have proved that Kevlar fiber-reinforced Epoxy polymer (KRE) composites are the most advantageous and exciting innovative material in bulletproof vests and body armor applications. This review thoroughly examines the physical and structural features of Kevlar fibers, epoxy resins, and Kevlar-epoxy composites. Along with different production methods that control composite quality and performance, it also emphasizes important theoretical factors affecting their mechanical and thermal behavior. The review concludes by discussing KRE composites' recent developments, difficulties, and potential as the next generation of materials for body armor and bulletproof vests. Also, the authors made every attempt to offer to this study a credible source in the field of Kevlar fiber-reinforced Epoxy polymer composite to aid future investigations by other researchers.

This paper focuses on the development of thermosetting resins with lightweight, excellent thermal stability and oxidation resistance. Specifically, the curing behavior and thermal properties of benzoxazines incorporating nitrile groups at the ortho, meta, and para positions of amine moiety were systematically evaluated to identify the most favorable chemical structures. Furthermore, thermal stability analysis revealed that C2-abn exhibited a high char yield of 68.49% at 800 degrees C. Flame exposure tests and EDS analysis indicated that C2-abn showed superior oxidation resistance with a low oxygen content of 18%. This paper provides insights into how nitrile positioning influences polymer network formation, crosslinking, and thermal performance. Also, the design and performance of high-performance benzoxazines emphasize their potential for application, which can contribute to the advancement of defense materials technology.

Styrene-butadiene rubber (SBR) is widely used in tire and damping applications, yet its reinforcement with polar nanofillers is often limited by weak interfacial adhesion in nonpolar matrices. Here, electron-beam (EB) curing is combined with glycidyl methacrylate (GMA) to promote interphase formation between non-functionalized aramid nanofibers (ANFs) and SBR without prior ANF surface modification. ANFs were prepared via KOH/DMSO-assisted fibrillation and incorporated into SBR using a masterbatch route, followed by compounding with GMA and EB irradiation. Process optimization shows that an EB dose of 150 kGy maximizes tensile strength despite monotonic increases in crosslink density with dose, indicating that excessive irradiation (200 kGy) causes over-densification and/or chain scission that reduces extensibility and strength. FT-IR evidences epoxy ring opening and consumption of GMA-associated epoxy/vinyl features after EB curing, consistent with GMA-mediated coupling at the ANF-SBR interface. Swelling analysis reveals that crosslink density increases with ANF content only when GMA is present, implying the formation of interfacial networks. SEM fracture morphologies corroborate this interpretation: interfacial voids persist in SBR/ANF controls but largely vanish in SBR/GMA/ANF composites. Under optimized conditions (5 phr GMA, 150 kGy), tensile strength increases systematically with ANF loading, reaching a similar to 43% improvement at the highest ANF content investigated. Dynamic mechanical analysis shows a reduced tan delta at T-g, indicating restricted chain mobility associated with enhanced interfacial interactions and increased crosslink density.

A multiscale modeling approach is proposed to investigate the mechanical properties of carbon fiber/silicon carbide (C/SiC) composites fabricated by chemical vapor infiltration (CVI) process. First, reactive molecular dynamics simulations are conducted to estimate the mechanical properties of the SiC matrix fabricated via CVI. Subsequently, a two-level micromechanics-based homogenization is developed to account for the effects of various constituents (e.g., porosity and carbon fiber) on the mechanical properties of the C/SiC composites. A series of numerical parametric studies is performed to examine the influence of the model parameters on the mechanical properties of the C/SiC composites. In addition, experimental investigations, including tensile tests and scanning electron microscopy, are conducted to validate the proposed modeling approach. The results indicate that the proposed modeling approach provides predictions that are in good agreement with the experimental results, thereby demonstrating the effectiveness of the proposed modeling scheme.

Cellulose is a readily available, renewable, natural polymer and biodegradable that can be used to make polymer nanocomposites. Inorganic-organic composites are currently gaining popularity due to their flexibility. Hybrid nanocomposites made of cellulose and magnetic nanoparticles (NPs) have received a lot of interest over the past few years, because of their strong magnetic, chemical stability, biocompatibility, and simplicity of functionalization, Fe3O₄ nanoparticles are frequently utilized in cellulose nanostructures. These characteristics make them perfect for applications including medication administration, adsorption, catalysis, and smart materials. In this review, we summarize the current state-of-the-art manufacturing techniques for Fe3O4 supported cellulose-based composites, with a particular emphasis on their characteristics and ongoing study advancements related to the utilization of Fe3O4 supported cellulose-based composites for metal adsorption, water/oil separation, dye degradation, biomedical and other applications. This work offers a critical and comparative evaluation of Fe3O4/cellulose hybrid composites, highlighting synthesis techniques, multifunctional applications, and methodically identifying current research gaps and future directions, in contrast to earlier reviews that primarily provide descriptive overviews. From 2010 to 2025, pertinent literature was methodically gathered from major databases such as Web of Science, Scopus, and ScienceDirect using keywords like “cellulose nanocomposites,” “Fe3O4 nanoparticles,” and “hybrid composites.” Studies that documented physicochemical characteristics, synthesis methods, or applications were included, while purely theoretical or irrelevant works were excluded. Furthermore, we will underline that this review outlines the future research areas and upcoming issues, thereby distinguishing it from generic narrative reviews.

This study investigated an in situ phase-separated epoxy network exhibiting high glass transition temperature (Tg) and enhanced fracture toughness for aerospace composite applications. A disulfide-containing curing agent, 4,4′-dithiodianiline (4,4′-DTDA), was introduced into a tetraglycidyl-4,4′-diaminodiphenylmethane (TGDDM)/diaminodiphenyl sulfone (DDS) epoxy system. During curing, DTDA spontaneously aggregated to form a second phase, resulting in a phase-separated morphology. The optimal formulation—TGDDM with 3,3′-DDS and 4,4′-DTDA in a 7:3 ratio—achieved a fracture toughness of 2.0 MPa·m1/2 and a Tg of 237 °C, surpassing many conventional aerospace-grade epoxies. In contrast, the TGDDM/3,3′-DDS system without DTDA exhibited a higher Tg of 246 °C but significantly lower fracture toughness of 0.91 MPa·m1/2, indicating a 120

Fracture toughness is a key property of epoxy resins with a high glass transition temperature (Tg), used in carbon fiber/epoxy composites for aerospace applications. Conventional toughening methods rely on adding toughening agents, often compromising the processibility and thermal stability. This study introduces a simple self-toughening approach that enhances the fracture toughness without sacrificing other properties by controlling the cured epoxy network structure. Tetraglycidyl 4,4'-diaminodiphenylmethane (TGDDM) epoxy resin was cured using mixtures of structural isomeric curing agents, 3,3'- and 4,4'-diaminodiphenyl sulfone (3,3'- and 4,4'-DDS), at ratios of 7:3, 5:5, and 3:7. The optimal 7:3 ratio produced a resin with 30% higher fracture toughness compared to TGDDM/3,3'-DDS and 100% higher than the TGDDM/4,4'-DDS system. The Tg of the self-toughened resin ranged from 241 to 266 °C, which was intermediate between the Tg values of the TGDDM/3,3'-DDS and TGDDM/4,4'-DDS systems. This improvement is attributed to the higher crosslink density and reduced free volume of the epoxy network. These findings demonstrate that simply mixing isomeric curing agents enables self-toughening, providing a practical and efficient strategy to enhance the performance of high-Tg epoxy resins in advanced composite applications.

This work presents a new approach for optimizing the carbonization conditions of polyacrylonitrile (PAN)-based fibers by tracing the microstructural changes during the carbonization process. Variations in the radial direction of the carbon fibers were also examined, emphasizing their correlation with temperature and duration. Changes in the outermost structure (surface) and radial heterogeneity were strongly correlated with tensile strength. Furthermore, the analysis focuses on structural changes in carbon crystallites and voids, which were analyzed using X-ray techniques, including wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS). The size of the carbon crystallites increased exponentially with carbonization temperature and duration, forming master curves for crystallite-related properties, such as tensile modulus and void dimensions, with an identical shifting factor. These results suggest that structural changes in the radial direction critically affect mechanical properties. Based on these analyses, an optimal carbonization process was proposed, involving a duration of 2 min at 1300 degrees C, which resulted in a tensile strength of 3.97 GPa and a tensile modulus of 234 GPa. These findings offer a framework for optimizing the carbonization conditions to enhance the production of high-quality carbon fibers.

Epoxy-based composite materials, widely used in various industries such as coatings, adhesives, aerospace, electronics, and biomedical engineering, remain a topic of global interest due to their varying characteristics based on the base resin and curing agents used. This paper employs molecular dynamics simulation to examine the thermal and mechanical properties, as well as molecular behaviors, of epoxy systems cured with diglycidyl ether of bisphenol F as the base resin and aromatic amine curing agents, specifically the meta structure of 3,3'-diaminodiphenyl sulfone (3,3'-DDS) and the para structure of 4,4'-diaminodiphenyl sulfone (4,4'-DDS). The 3,3'-DDS system demonstrated a greater density and Young's modulus than the 4,4'-DDS system. This tendency was analyzed based on differences in molecular fractional free volume and cohesive energy density (CED). The 4,4'-DDS system exhibits a higher glass transition temperature (Tg) compared to the 3,3'-DDS system, with values of 406.36 K and 431.22 K, respectively. To understand this behavior, we examined atomic-scale displacements at Tg through mean squared displacement analysis, which revealed that the onset of molecular motion occurs at a lower temperature in the 3,3'-DDS system. Molecular-level study reveals how the structural features of each curing agent appear in thermal and mechanical properties, offering important insights for epoxy system development.

Owing to the necessity of developing airframe materials for military unmanned aerial vehicles (UAVs), capable of operating in extreme environments, aerospace-grade composite materials were developed using a high-toughness epoxy-resin system, and were subsequently analyzed and evaluated. The phase transition behavior of a high- toughness epoxy-resin system was modeled and simulated as a function of the toughening agent, polyethersulfone (PES), and its content to optimize the resin system. Reliability was ensured through experimental validation. At the maximum PES content compatible with the base epoxy-resin and curing agent contents, the epoxy-resin system exhibited the highest tensile strength and toughness. However, results from preliminary tests performed using the pilot process revealed that an increase in viscosity beyond a certain level due to the addition of PES rendered it unsuitable for application in mass-production processes. The optimal composition of the high- toughness epoxy-resin system suitable for mass production was determined based on the results of the resin paper production using the pilot process. High-toughness carbon fiber-reinforced plastics (CFRPs) were then mass produced, and their characteristics were compared with those of conventionally toughened CFRPs and the pilot products. The results confirmed that compared with the conventionally toughened CFRPs, the massproduced CFRPs containing the high-toughness resin system showed 246%, 728%, 392% and 480% improvement in compression-after-impact strength, Mode-I interlaminar fracture toughness (ILFT), Mode-II ILFT for crack initiation, and Mode-II ILFT for crack propagation, respectively. In addition, these composites were used to manufacture UAV wings to evaluate their applicability in airframe structures.

Controlling the microstructure of polyacrylonitrile (PAN) precursor fibers is critical for manufacturing highperformance carbon fibers. This study investigates the impact of coagulation conditions, specifically DMF content in methanol bath and temperature, on the structural development and mechanical properties of carbon fibers. Rapid phase separation, achieved in pure methanol at -10 degrees C (MeOH100_-10), produced precursor fibers with a well-developed crystal structure and small, highly-oriented microvoids. In contrast, slower phase separation in a 30 vol% DMF bath at 30 degrees C (MeOH70_30) resulted in a poorly-developed crystal structure with large, misaligned microvoids. Although the crystalline differences minimized after carbonization, the microvoid and radial structural differences were retained. The rapidly phase-separated MeOH100_-10 precursor fiber produced a carbonized structure with well-oriented microvoids. Conversely, the slowly phase-separated MeOH70_30 precursor fiber yielded a carbon fiber with a poor microvoid orientation. These structural differences directly affected the mechanical properties of carbonized fibers. The tensile strength and modulus of MeOH100_-10 carbon fiber were 18% and 11% higher than those of MeOH70_30 carbon fiber, respectively. These findings demonstrate that phase separation behavior under different coagulation conditions significantly affects precursor microstructure and carbon fiber performance.

With the depletion of fossil fuels and growing environmental concerns, the modernized era of technology is in desperate need of sustainable and eco-friendly materials. The industrial sector surely has enough resources to produce cost-effective, renewable, reusable, and sustainable raw materials. The family of very porous solid materials known as aerogels has a variety of exceptional qualities, such as high porosity, high specific surface area, ultralow density, and superior thermal, acoustic, and dielectric properties. As a result, aerogels have the potential to be used for many different purposes, such as absorbents, supercapacitors, energy storage, and catalytic supports. Recently, cellulose nanofibril (CNF) aerogels have attracted remarkable attention for their large-scale utilization because of their high absorption capacity, low density, biodegradability, large surface area, high porosity, and biocompatibility. Recent advancements have confirmed that CNF-based hybrid aerogels can be proposed as the most privileged and promising novel material in various applications. This comprehensive review highlights the recent reports of the CNF-based hybrid aerogels, including their properties and frequent preparation approaches, in addition to their new applications in the areas of fire retardant, water and oil separation, supercapacitors, environmental, and CO2 capture. It is also assumed that this article will promote additional investigation and establish innovative capabilities to enhance novel CNF-based hybrid aerogels with new and exciting applications.

Photocatalytic hydrogen (H2) generation from water by using solar energy and photocatalyst is a green and sustainable method to address the energy problems. The development of an extremely efficient photocatalyst is necessary for the commercial and large-scale making of H2. As regards semiconductors based photocatalysts, CdS has mesmerized widespread concentration owing to its moderately narrowing band gap for visible light response and adequately negative potential of the conduction band edge for proton reduction. Previous reports showed that the CdS based heterojunction has tremendous photoactivity for photocatalytic hydrogen production. This comprehensive review highlights the recent reports of design and preparation methods of CdS based heterojunctions. In this perspective, the CdS based heterojunction were categorized as noble metal supported CdS nanocomposites, transition metal supported CdS nanocomposites, GO supported CdS nanocomposites, semiconductors supported CdS nanocomposites, non-metals supported CdS based photocatalyst, metal complexes supported CdS based photocatalysts, carbon nanotubes supported CdS based photocatalysts and metal-organic frameworks supported CdS based photocatalysts. It is expected that this review will stimulate further investigation and open up new possibilities for raising new CdS heterostructure with new and exciting applications. In conclusion, encouraged by the large number of tremendous examples, we have presented some perspectives for the future improvement of CdS based photocatalysts.

In this study, surface modification aimed to enhance the compatibility between a hydrophilic inorganic filler and polypropylene (PP) matrix using hydrophobic treatment. Lauric acid, butyl acrylate, and maleic anhydride were employed to modify the filler surface. After treatment, inorganic filler/PP composites were produced using melt-mixing and extrusion–injection molding processes. The study focused on investigating compatibility and migration behavior between the filler and matrix. The findings indicated that hydrophobic modification, specifically with butyl acrylate and maleic anhydride, improved migration issues in nano-whisker, while maintaining favorable mechanical properties even under accelerated thermal aging. However, excessive hydrophobicity induced by superhydrophobic treatment using lauric acid led to reduced compatibility with the matrix, compromising its effectiveness. Consequently, the study revealed the potential of surface modification to enhance interfacial properties and mitigate migration concerns in PP composites for automotive applications.

Over the past few years, transition metal carbides, nitrides, and carbonitrides, commonly referred to as MXenes have been discovered and utilized quickly in a range of technical fields due to their distinctive and controlled characteristics. MXenes are a new class of two-dimensional (2D) materials that have found extensive use in a variety of fields, including energy storage, catalysis, sensing, biology, and other scientific disciplines. This is because of their exceptional mechanical and structural characteristics, metal electrical conductivity, and other outstanding physical and chemical properties. In this contribution, we review recent cellulose research advances and show that MXene hybrids are effective composites that benefit from cellulose superior water dispersibility and the electrostatic attraction between cellulose and MXene to prevent MXene accumulation and improve the composite's mechanical properties. Electrical, materials, chemical, mechanical, environmental, and biomedical engineering are all fields in which cellulose/MXene composites are used. These properties and applications-based reviews on MXene/cellulose composite, critically analyze the results and accomplishments in these fields and provide context for potential future research initiatives. It examines newly reported applications for cellulose nanocomposites assisted by MXene. To support their development and future applications, perspectives and difficulties are suggested in the conclusion.

The accelerated thermal aging of plastics causes the migration of additives onto specimen surfaces. This is commonly called the “blooming” or “whitening” phenomenon and has long been an issue in the automotive applications of thermoplastic composites. Still, there is a lack of scientific reports regarding crystallization behavior to our best knowledge. This study investigates the mechanism and characteristics of slip agent migration onto injection-molded composite surfaces depending on the behavior of nanocrystallization with thermal aging and develops a method to evaluate the correlation between the internal and external crystallization size and migration of the composites. Slip agent migration was investigated by increasing the spherulite size of PP/slip agent composites, as measured by X-ray diffraction analysis at different periods. It was found that as the crystalline area increased, the low molecular weight slip agents present in the amorphous region migrated to the specimen surface owing to the absence of interactions with the polymer. In addition, surface elemental analysis, lightness, and roughness confirmed that the slip agents migrated to the surface in accelerated thermal aging conditions. The findings of this work provide a better understanding of the correlation between thermal aging and the migration phenomenon of slip agents on the surfaces of thermoplastic composites. Graphical abstract