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Modern polymer‐based technical components not only have to fulfill demanding mechanical‐structural properties but need to integrate different functions to yield hybrid systems for complex operations. Typically, neither materials nor processing technologies are fully compatible with each other. The aim of the work is to combine the advantages of seemingly incompatible manufacturing processes such as high‐volume injection molding (IM) and precision additive manufacturing to produce functional and customized hybrid materials. IM is widely used for polymer processing but stands against high investment costs for tailor‐made molds with high‐resolution features. They focus on overprinting of injection‐molded parts made of thermoplastic polyurethane (TPU) with microstructures via projection‐microstereolithography (PµSL) to generate hybrid polymer materials with spatially tailored stiffness, enabling selective reinforcement, resulting in an E modulus increase of 195% compared to mere IM‐processed TPU. With that, the hybridization of processing methods is showcased to extend the product properties of polymer materials obtained via either IM or PµSL printing that have, prospectively, a maximum degree of individualization as well as a multitude of structural and functional features at the same time. To achieve optimum interfacial adhesion, the influence of surface roughness is studied, and reinforcement effects of different overprinted microstructure types are evaluated. [ABSTRACT FROM AUTHOR]

The construction of the nanohybrid composed of two carbonaceous nanomaterials is a promising strategy to inhibit their aggregation, and effectively exert the advantages of their excellent mechanical properties as reinforcement for polymers. Here, carbon nanotubes (CNTs) were in situ perpendicularly growing on the surface of graphene oxide (GO) through metal-organic frameworks (MOF)-derived strategy by chemical vapor deposition (CVD), aiming to facilitate their dispersion on poly(l-lactic acid) (PLLA) bone scaffold fabricated by selective laser sintering (SLS). Specifically, GO provided nucleation sites for the growth of MOF, and worked as the templates when CNTs grew, in which MOF provided catalysts and carbon sources simultaneously. The precursor was heated to 550 °C and kept for 2 h, then heated to 900 °C and kept for 2 h before cooling. The obtained nanohybrid (GO@CNT) exhibited a superior dispersion state than the pure GO in the scaffold at the same loading, especially when the loading was 0.75 wt%. Adding 0.75 wt% GO@CNT endowed the scaffold with a remarkable increment in tensile strength and compressive strength of 13.36 MPa and 24.72 MPa with enhancement of 55.35% and 18.85%, respectively, compared to the scaffold containing 0.75 wt% GO. A crack extension model combined with experiment results was proposed to better understand reinforcement mechanisms. Additionally, the scaffold containing GO@CNT exhibited benign cytocompatibility with a cell-spreading area of 86.31% and cell density of 564 cells/mm2 after culturing for 5 d according to the results of cell adhesion and immunofluorescence tests, making it a promising candidate for bone defect repair.

Graphene is a perfect 2D crystal of covalently bonded carbon atoms and constitutes the building block for all graphitic structures. Its superior properties make it an attractive material for a variety of technological applications. However, mass production does not meet the initial expectations. Chemical Vapor Deposition (CVD) is currently the only available method for large‐scale automated production, but the produced graphene sheets suffer from structural and morphological defects that degrade considerably the mechanical and other physical properties of synthesized graphene. Recently, the use of liquid metal catalysts (LMCat) has been proposed as an alternative platform for facile and high‐quality synthesis of single‐crystal graphene. Herein, simultaneous Raman spectroscopy combined with mechanical testing is adopted confirming that the reinforcing efficiency of the LMCat graphene is greatly improved. In fact, the effective Young's modulus of LMCat graphene has been found ≈630 GPa, which is significantly higher than the graphene grown on solid Cu substrate due to differences in the morphology of Cu substrate. Overall, this work paves the way for the development of defect‐free graphene of quality comparable to exfoliated flakes, and this will have a major technological impact for many applications. [ABSTRACT FROM AUTHOR]

Light‐cured polymer composites incorporating particle reinforcements have been adopted for a wide range of engineering applications. Nevertheless, micro‐filled composites exhibit insufficient strength despite good abrasion resistance. Conversely, nano‐filled counterparts possess enhanced strength but easily generate particle agglomeration. Hybrid filling has therefore been utilized in previous studies to combine the advantages of different components, but conclusive results have not been obtained. Within this study, the effects of hybrid filling on the strengthening mechanism and curing kinetics of light‐cured polymer composites were investigated by multi‐scale mechanical tests, in‐situ near‐infrared spectroscopy, scanning electron microscope, and finite element simulations. It was found that hybrid filling led to an average increase in Young's modulus by ~3.94%, the hardness by ~5.81%, the tensile strength by ~10.44%, and the degree of conversion by ~2.54% compared to micro‐filling at the same filler content. Besides, hybrid filling showed more reduced particle agglomeration compared to nano‐scale filling. Finite element analysis revealed that hybrid filling effectively enhanced the load‐bearing capacity of the matrix. Overall, the experimental results unveil a mechanism of particle reinforcement that can be extrapolated to various particle‐filled polymers across different length scales. These findings provide a versatile manufacturing technique for composites with heightened mechanical reinforcement and are expected to guide the application in the field of photo‐polymeric materials. Highlights: Light‐cured polymer composites incorporating hybrid silica particles were prepared.The strengthening mechanism was investigated by multi‐scale mechanical tests.Hybrid filling could lead to an increase in material strength compared to micro‐filling.Hybrid filling exhibited reduced particle agglomeration in comparison to nano‐filling. [ABSTRACT FROM AUTHOR]

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Compared with commercial polyolefin membranes, electrospun polymeric membranes have the advantages of higher porosity and better electrolyte wettability, but their poor mechanical performance limits their industrial use as battery separators. In this work, a layer‐to‐layer electrospinning is used for fabrication of PVdF@PMMA membranes, in which fibers in adjacent layers are arranged at a certain angle (0°, 30°, 60°, 90°). The as‐electrospun membranes are further hot‐pressed to boost their mechanical strength. Various techniques are employed to evaluate the membranes, such as scanning electron microscopy, differential scanning calorimetry, contact angle measurement, electrochemical impedance spectroscopy, and linear sweep voltammetry. The results show that polymethyl methacrylate partially melts during the hot‐pressing treatment, causing adjacent fibers in the membranes to bridge. The obtained membranes show different tensile strength values with the various angles between fibers. When the angle is 30°, the tensile strength can reach 22.09 MPa and higher porosity (74.68%), greater liquid electrolyte absorption (612.36%) than that of commercial polyolefin membrane are harvested. The lithium‐ion cell assembly with the membrane separator exhibits a discharge capacity reaching 142 mAh g−1 and an excellent capacity retention of 90.7%. This present study provides an innovative and promising approach for the fabrication of high‐performance battery separator by electrospinning. Highlights: PVdF@PMMA membranes are prepared by a layer‐to‐layer electrospinning.In the membranes, fiber orientation in adjacent layers is kept at a certain angle.Hot‐pressing further boosts mechanical performance of the membranes.Membranes with different angle of fibers show various mechanical strengths. [ABSTRACT FROM AUTHOR]

Abstract Graphene is a perfect 2D crystal of covalently bonded carbon atoms and constitutes the building block for all graphitic structures. Its superior properties make it an attractive material for a variety of technological applications. However, mass production does not meet the initial expectations. Chemical Vapor Deposition (CVD) is currently the only available method for large‐scale automated production, but the produced graphene sheets suffer from structural and morphological defects that degrade considerably the mechanical and other physical properties of synthesized graphene. Recently, the use of liquid metal catalysts (LMCat) has been proposed as an alternative platform for facile and high‐quality synthesis of single‐crystal graphene. Herein, simultaneous Raman spectroscopy combined with mechanical testing is adopted confirming that the reinforcing efficiency of the LMCat graphene is greatly improved. In fact, the effective Young's modulus of LMCat graphene has been found ≈630 GPa, which is significantly higher than the graphene grown on solid Cu substrate due to differences in the morphology of Cu substrate. Overall, this work paves the way for the development of defect‐free graphene of quality comparable to exfoliated flakes, and this will have a major technological impact for many applications.

The recycling of waste materials in asphalt pavements is pivotal for advancing the road industry, offering numerous environmental, economic, and societal benefits. This study explores the recycling potential of waste electronic cigarette butts (E-CBs) within stone mastic asphalt (SMA) mixtures, serving as a substitute for cellulose fibres and enhancing mechanical performance. Considering the critical role of fibre size in asphalt mixtures, two different E-CB shredding sizes (10 and 15 mm) were selected for examination. Additionally, the influence of the plastic component within E-CBs was investigated. The stabilizing effects of using the shredded E-CBs were evaluated via drain-down tests, followed by a series of standard laboratory tests aimed at assessing physical and mechanical properties. Results demonstrate acceptable drain-down properties, volumetric properties, and moisture susceptibility for the use of all four shredded E-CBs. Among the four mixtures incorporating the waste fibres, the utilization of 15 mm shredded E-CBs without plastic constituents yielded the highest values for indirect tensile strength (ITS) and indirect tensile stiffness modulus (ITSM), coupled with excellent water susceptibility and rutting performance. It can be considered a promising alternative to the traditional cellulose fibre. Larger shredded E-CBs exhibited potential for improving mechanical properties, encompassing cohesion, stiffness modulus, and rutting resistance. Although plastic inclusion can enhance rutting resistance, the higher thermal susceptibility associated with plastic warrants careful consideration. Future research may focus on investigating the fatigue and low-temperature cracking properties, as well as the reinforcing mechanisms of shredded E-CBs in asphalt mixtures using micro-characterization techniques.

Nanoporous graphene membranes are attractive for molecular separations, but it remains challenging to maintain sufficient mechanical strength during scalable fabrication and module development. Inspired by the composite structure of cell membranes and cell walls, a large‐area atomically thin nanoporous graphene membrane supported by a fiber‐reinforced structure with strong interlamellar adhesion is designed. Compared with other graphene‐based membranes of large scale, the fracture stress, fracture strength, and tensile stiffness of the composite membranes can be enhanced by a factor of 17, 67, and 94, respectively. This fiber‐reinforced structure also confers stability of the composite membrane to different curvature states and repeated bending processes after 10 000 times, which provides an opportunity for modularization. The breathable function of such membrane with an ultrahigh gas permeance (≈8.6–23 L m−2 d−1 Pa−1) and an ultralow water vapor transportation rate (WVTR) (≈23–129 g L m−2 d−1) is observed, superior to most commercial materials. This work provides a facile method to fabricate large‐area graphene membranes and paves the road to practical application in the membrane separation field for other 2D films. [ABSTRACT FROM AUTHOR]

ABSTRACTMetal oxide nanorods exhibit promising potential as reinforcement fillers in various polymer matrices, but their application in the Multi Jet Fusion (MJF) technique is rarely reported. In this work, surface-modified zinc oxide nanorods (SMZnO) were synthesized and incorporated into polyamide 12 (PA12) powder to enhance the mechanical properties of the MJF-printed parts. Compared to ZnO, SMZnO exhibited better dispersion, resulting in markedly enhanced mechanical performances. The ultimate tensile strength and the Young's modulus of the MJF-printed SMZnO/PA12 nanocomposites were 62.02 MPa and 2.28 GPa in the X orientation and 64.07 MPa and 2.34 GPa in the Y orientation, equivalent to 27.85%, 59.44%, 29.12%, and 54.97% increments, respectively. The flexural strength and modulus demonstrated similar improvements in the X and Y orientations, confirming the uniform mechanical enhancement effect of homogenously distributed SMZnO. This work provides a novel and facile approach for the additive manufacturing of polymeric nanocomposites with superior mechanical performance.

Anisotropic two-dimensional (2D) materials, such as boron nitride nanoplatelets (BNNP), are excellent polymer reinforcement candidates due to their superior and tailorable thermal and mechanical properties. A significant challenge with integrating nanosized 2D fillers in polymer matrices is their agglomeration tendency, which has detrimental effects on the nanocomposite's properties. Freeze-drying enables the construction of free-standing 2D material networks to be used as composite nanofillers. In this study, ultralight BNNP lamellar foams (0.05 g/cm3 dense and 97% porous) were fabricated via freeze-drying. The BNNP foams presented highly anisotropic thermal and mechanical behavior due to their lamellar morphology. The thermal conductivity of the foam along its lamellar walls is 0.31 W/(m·K), (4× greater), while it is 0.08 W/(m·K) throughout the pores. The anisotropy in the thermal properties of 2D foams is modeled. The mechanical behavior of BNNP foams was studied via quasi-static and cyclic nanoindentation. The lamellar foams are stronger (10×) along the wall direction (11.3 MPa) than across the walls (1.3 MPa). Mechanical properties were modeled by using the Gibson and Ashby model for cellular materials. A protocol is established to design 2D material foams with different concentrations and particle sizes as composite nanofillers with tailorable thermal and mechanical properties for thermal management applications. [ABSTRACT FROM AUTHOR]

The tendon tissue has little regenerative potential. Hence, tendon healing after an injury is characterized by the formation of fibrous scar tissue. Tendon injury is the most common disease condition seen in orthopedics and causes pain, dysfunction, and work-related disorders. The failure of tendon healing and regeneration after rotator cuff repair in the shoulder joint is commonly observed and is a difficult problem to manage. Tendon regeneration for the management of tendon injury through tissue reengineering is one of the most interesting topics in orthopedics. Currently, for the biological and mechanical reinforcement of tendon regeneration, biologic agents such as mesenchymal stem cells, platelet-rich plasma (PRP), polydeoxyribonucleotide (PDRN), autologous graft, homologous grafts, acellular dermal matrix or atelocollagen, etc. are often used in clinical practice and have sometimes shown good results. However, to ensure efficacy and results long-term follow up is necessary. [ABSTRACT FROM AUTHOR]

The formation of covalently cross-linked 3D network makes it difficult to recycle conventional vulcanized rubbers. Introducing dynamic covalent bonds such as reversible ester bonds into the rubber network is a feasible method to solve this issue. However, the low mechanical properties of rubber with only reversible ester bonds make it unsuitable for most practical applications. This work reports a strengthened biobased epoxidized natural rubber/adipic acid/cellulose nanocrystal (ENR/AA/CNC) composite in which biobased AA covalently cross-links ENR to form a network with exchangeable β-hydroxyl ester bonds. This network is able to rearrange its topology at high temperatures, causing the ENR/AA/CNC composite to exhibit certain reprocessing capabilities. Meanwhile, the CNCs form a mass of hydrogen bonds between their hydroxyl groups and the hydrophilic groups of ENR chains, giving the ENR/AA/CNC composite an enhanced mechanical performance. [ABSTRACT FROM AUTHOR]

The adhesion strategies of the gecko's toe through surface adaptation of spatulas to increase contact area and the snail's epiphragm via dehydration‐induced solidification to lock interfaces are combined to design a class of adhesion‐switchable hydrogels. The hydrogels are made via incorporating CH3COONa·3H2O salt (SA) into polyacrylamide (PAM) aqueous networks to construct supersaturated and stimuli‐responsive phase change materials (PAM‐SA). The crystallization dramatically strengthens the mechanical properties, and tensile Young's moduli are 340.7 and 0.1 MPa for crystalline C‐PAM‐SA‐120% and soft PAM hydrogel. As a result, PAM‐SA‐120% shows excellent adhesive performance (adhesion strength, 348 kPa) compared with PAM hydrogel adhesive (adhesion strength, 7 kPa). The stimuli‐induced crystallization from H‐PAM‐SA‐120% phase change hydrogels releases thermal controllably, which can be utilized for thermochromic materials and thermotherapy. [ABSTRACT FROM AUTHOR]

[Display omitted] • The combination of the inorganic structure with the flexible aliphatic segment was proposed to fabricate P-decorated POSS. • Epoxy resins with P-decorated POSS maintained high transparency. • The resultant P-decorated POSS showed both high flame retardancy and mechanical reinforcement for epoxy resins. • The specific mechanism of action was analyzed. Epoxy resins (EPs) are known for their durability, strength, and adhesive properties, which make them a versatile and popular material for use in a variety of applications, including chemical anticorrosion, small electronic devices, etc. However, EP is highly flammable due to its chemical nature. In this study, phosphorus-containing organic–inorganic hybrid flame retardant (APOP) was synthesized by introducing 9, 10-dihydro-9-oxa-10‑phosphaphenathrene (DOPO) into cage-like octaminopropyl silsesquioxane (OA-POSS) via Schiff base reaction. The improved flame retardancy of EP was achieved by combining the physical barrier of inorganic Si-O-Si with the flame-retardant capability of phosphaphenanthrene. EP composites containing 3 wt% APOP passed the V-1 rating with a value of LOI of 30.1% and showed an apparent reduction in smoke release. Additionally, the combination of the inorganic structure and the flexible aliphatic segment in the hybrid flame retardant provides EP with molecular reinforcement, while the abundance of amino groups facilitates a good interface compatibility and outstanding transparency. Accordingly, EP containing 3 wt% APOP increased in tensile strength, impact strength, and flexural strength by 66.0 %, 78.6 %, and 32.3 %, respectively. The EP/APOP composites had a bending angle lower than 90°, and their successful transition to a tough material highlights the potential of this innovative combination of the inorganic structure and the flexible aliphatic segment. In addition, the relevant flame-retardant mechanism revealed that the APOP promoted the formation of a hybrid char layer containing P/N/Si for EP and produced phosphorus-containing fragments during combustion, showing flame-retardant effects in both condensed and vapor phases. This research offers innovative solutions for reconciling flame retardancy & mechanical performances and strength & toughness for polymers. [ABSTRACT FROM AUTHOR]

Abstract One-dimensional (1D) SiO2 nanofibers (SNFs), one of the most popular inorganic nanomaterials, have aroused widespread attention because of their excellent chemical stability, as well as unique optical and thermal characteristics. Electrospinning is a straightforward and versatile method to prepare 1D SNFs with programmable structures, manageable dimensions, and modifiable properties, which hold great potential in many cutting-edge applications including aerospace, nanodevice, and energy. In this review, substantial advances in the structural design, controllable synthesis, and multifunctional applications of electrospun SNFs are highlighted. We begin with a brief introduction to the fundamental principles, available raw materials, and typical apparatus of electrospun SNFs. We then discuss the strategies for preparing SNFs with diverse structures in detail, especially stressing the newly emerging three-dimensional SiO2 nanofibrous aerogels. We continue with focus on major breakthroughs about brittleness-to-flexibility transition of SNFs and the means to achieve their mechanical reinforcement. In addition, we showcase recent applications enabled by electrospun SNFs, with particular emphasis on physical protection, health care and water treatment. In the end, we summarize this review and provide some perspectives on the future development direction of electrospun SNFs.

Aerogels are three-dimensional hierarchical nanoporous materials with many applications depending on their unique properties. Although silica aerogels have been studied extensively and industrialized, they cannot withstand high temperatures exceeding 650 °C for a long period. Metal oxide aerogels are the best candidates for high-temperature applications due to their excellent thermal and chemical stability. Among them, alumina, zirconia and titania aerogels show the best thermal stability and have drawn great attention in recent years. This paper overviews single-component metal oxide (alumina, zirconia, titania aerogels, and other metal oxide aerogels) and composite metal oxide aerogels (multicomponent composite aerogels and mechanical reinforced aerogels), including their preparation, characterization, and properties in high-temperature applications, to provide a helpful resource for researchers and technicians. Highlights: This paper reviews the main progress of metal oxide aerogels in recent years. Specific surface areas and phase transitions of metal oxide aerogels are discussed. High-temperature applications of thermal insulation and catalyst are introduced. [ABSTRACT FROM AUTHOR]

This study mainly aims both to prepare well-shaped crosslinked 3,3,4,4,5,5,6,6,7,7,8,8,8 tridecafluorooctyl-4-(acrloyloxy) benzoate (ABCF13) polymer microspheres and to investigate the influences of the prepared microspheres addition on the crystallinity, thermal, mechanical and morphological features of high density polyethylene (HDPE). The suspension polymerization method was used for the production of well-defined microspheres and, the content of the microspheres varied from 1.0% to 10.0% in the composites. The characterization of crosslinked poly(ABCF13) microsphere-loaded HDPE composites were performed via powder X-ray diffraction, differential scanning calorimeter, universal mechanical (tensile and impact) testers and scanning electron microscope (SEM) techniques. According to the experimental findings, a and b unit cell parameters increased initially and reached maxima with the sample including 5.0% microsphere, which were followed by dramatic decreases, while c parameter remained relatively unchanged. Thermal analysis also showed that the melting temperature of HDPE reduced with the initial loading of the microspheres, then stayed at a plateau value of about 129°C due to the formation of lattice distortions, generation of microstructural disorders and the defects in the crystal structures. The mechanical test results revealed that there existed considerable improvements in tensile strength, modulus and impact strength. The maximum tensile strength 25.66 MPa, elastic modulus 499.30 MPa and maximum absorbed energy in the impact test 26.84 kJ/m2 (29%, 42% and 41% improvement, respectively) were achieved with the blend involving 5.0% microsphere. After the maxima, the mechanical characters depicted weakening trend as the microsphere content increased in the matrix. The SEM analyses revealed that although there existed fibrillar formations in all samples, the extensions decreased with the increase of the microsphere content. While ductile behavior was observed with the formation of long-bulky extensions at low contents, brittleness started to prevail at high contents with some short and thin fibrils. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) and molybdenum disulphide (MoS2), have drawn more and more attention as reinforcement in polymer. However, their large specific surface area and strong van der Waals forces result in serious aggregations in polymer matrix, which restrains the reinforcement effect. In this study, MoS2 nanosheets were in situ synthesised vertically and uniformly on the surface of GO nanosheets with the help of a hexadecyl trimethyl ammonium bromide (CTAB) assisted hydrothermal process to facilitate their dispersion in polylactic acid (PLLA) scaffold manufactured via selective laser sintering (SLS). The experimental results revealed that the 1.5 wt% GO/MoS2 nanocomposite exhibited better dispersion state compared with the 1.5 wt% GO and 1.5 wt% MoS2 in PLLA matrix. Therefore, the PLLA scaffold loading 1.5 wt% GO/MoS2 presented 10.2 and 1461 MPa of tensile strength and modulus with enhancement of 61% and 58%, respectively, compared with the pure PLLA scaffold. The reinforcement mechanisms mainly included crack deflection, crack bridging, crack pinning and pulling out of GO/MoS2. What's more, the GO/MoS2-PLLA scaffold possessed benign cytocompatibility for cell behaviour, suggesting hopeful applications in bone defect repair. [ABSTRACT FROM AUTHOR]

Dental resin composites are universal restorative materials, and various kinds of fillers are used to reinforce their mechanical properties. However, a combined study on the microscale and macroscale mechanical properties of dental resin composites is missing, and the reinforcing mechanism of the composites is still not fully clarified. In this work, the effects of the nano-silica particle on the mechanical properties of dental resin composites were studied by combined dynamic nanoindentation tests and macroscale tensile tests. The reinforcing mechanism of the composites was explored by combining near-infrared spectroscopy, scanning electron microscope, and atomic force microscope characterizations. It was found that the tensile modulus increased from 2.47 GPa to 3.17 GPa, and the ultimate tensile strength increased from 36.22 MPa to 51.75 MPa, with the particle contents increasing from 0% to 10%. From the nanoindentation tests, the storage modulus and hardness of the composites increased by 36.27% and 40.90%, respectively. The storage modulus and hardness were also found to increase by 44.11% and 46.46% when the testing frequency increased from 1 Hz to 210 Hz. Moreover, based on a modulus mapping technique, we found a boundary layer in which the modulus gradually decreased from the edge of the nanoparticle to the resin matrix. Finite element modeling was adopted to illustrate the role of this gradient boundary layer in alleviating the shear stress concentration on the filler–matrix interface. The present study validates mechanical reinforcement and provides a potential new insight for understanding the reinforcing mechanism of dental resin composites. [ABSTRACT FROM AUTHOR]

Several studies have been conducted to improve the mechanical and other value-added properties of glass fiber-reinforced epoxy (GFRE) composites by the addition of different fillers. In this work, waste iron filings (WIFs) obtained from the steel industry were incorporated into GFRE composite samples in varying amounts of up to 50% (%w) to improve their mechanical and electrical properties. The results showed that, with increasing WIF loading from 0 w% to 50 w%, the resultant composite density gradually increased from 1.4 to 2.1 g/cm3. Surface hardness, Young's modulus, and tensile strength also increased significantly with the addition of up to 9 w% of WIF followed by a significant drop with more WIF addition due to agglomeration. Overall, Young's modulus of the GFRE samples with any WIF content was higher than that of the GFRE composite with no WIF. The elongation at break results showed that the GFRE samples were less ductile upon WIF addition, which decreased from 2% to 0.6% upon loading the composite with 50% WIF. In terms of electrical conductivity, the GFRE samples with WIF content of 15% or more were electrically conductive and their electrical conductivity increased with WIF content. It was clear that more WIF was needed to establish a percolated network in the GFRE composites to render them conductive. The electrical conductivity of the GFRE samples containing 15% WIFs was around 2.9 kS/m and increased to 35 kS/m upon the addition of 50% WIFs. These novel electrically conductive GFRE composites could be promising for structural dynamic monitoring systems in the construction industry. They also support the efforts for the utilization of waste materials towards a circular economy. [ABSTRACT FROM AUTHOR]

The current work studied the physical modification effects of non-covalent surfactant on the carbon-particle-filled nanocomposite. The selected surfactant named Triton™ X-100 was able to introduce the steric repelling force between the epoxy matrix and carbon fillers with the help of beneficial functional groups, improving their dispersibility and while maintaining the intrinsic conductivity of carbon particles. Subsequent results further demonstrated that the physically modified carbon nanotubes, together with graphene nanoplates, constructed an effective particulate network within the epoxy matrix, which simultaneously provided mechanical reinforcement and conductive improvement to the hybrid nanocomposite system. For example, the hybrid nanocomposite showed maximum enhancements of ~75.1% and ~82.5% for the quasi-static mode-I critical-stress-intensity factor and dynamic compressive strength, respectively, as compared to the neat epoxy counterpart. Additionally, the fine dispersion of modified fillers as a double-edged sword adversely influenced the electrical conductivity of the hybrid nanocomposite because of the decreased contact probability among particles. Even so, by adjusting the modified filler ratio, the conductivity of the hybrid nanocomposite went up to the maximum level of ~10−1–100 S/cm, endowing itself with excellent electro-thermal behavior. [ABSTRACT FROM AUTHOR]

Bioinspired polydopamine coatings have been widely used for the surface modification of various materials because of their strong adhesion, facile application method, and functionalization ability. However, dopamine has not been previously utilized as a coagulation agent for graphene oxide fibers (GOFs). In this study, we performed the wet spinning of GOFs using dopamine as a coagulation agent (denoted as DA‐GOFs) and successive polymerization of dopamine inside the fibers. The polymerized DA‐GOFs (pDA‐GOFs) exhibited enhanced mechanical properties with a 97% higher tensile strength than that of the fibers coagulated with CaCl2. The described dopamine‐assisted wet spinning and polymerization process were simple but effective method for preparing mechanically strong fibers, which can be potentially employed in flexible and wearable electronic applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • An interfacial hollow engineering strategy was proposed to fabricate nanohybrid flame retardants. • Bio-based phytic acid was assembled into the hollow cavity of mesoporous SiO 2 grafted with polydopamine-transition metal. • The resultant nanohybrid showed both high flame retardancy and mechanical reinforcement for epoxy resin. • The specific mechanism of action was analyzed. Nano flame retardants, as one of the key flame retardants in recent years, have been limited by poor efficiency and weak compatibility. In this study, we propose an interfacial hollow engineering strategy to tackle this problem by assembling P-phytic acid into the hollow cavity of mesoporous SiO 2 grafted with a polydopamine transition metal. In this design, the grafted polydopamine-metal coatings on the hybrids can greatly improve their interface compatibility with the polymer matrix, while the loaded phytic acid in the cavity contributes to enhance flame retardancy. Consequently, the resultant hierarchical P-loaded nanohybrids show both high flame retardancy and mechanical reinforcement for the polymer. Taking epoxy resin (EP, a typical thermosetting resin used in large quantities) as a representative, at only 1 wt% loading of the nanohybrids, the impact strength of the nanocomposites improved by 35.7% compared to pure EP. Remarkably, the hybrids can simultaneously endow EP with high flame retardancy (low heat release rate) and satisfactory smoke inhibition. Additionally, the flame-retardant mechanism analysis confirmed that the nanohybrid had a better catalytic carbonization effect on promoting the highly graphitized carbon layer, thereby suppressing the fire hazard of epoxy resins. This research offers a new interfacial hollow engineering method for the construct and design of high-performance EP with nanohybrids. [ABSTRACT FROM AUTHOR]

In this study, we developed a composite hydrogel based on Gellan gum containing Boswellia serrata extract (BSE). BSE was either incorporated directly or loaded into an MgAl-layered double hydroxide (LDH) clay to create a multifunctional cartilage substitute. This composite was designed to provide anti-inflammatory properties while enhancing chondrogenesis. Additionally, LDH was exploited to facilitate the loading of hydrophobic BSE components and to improve the hydrogel's mechanical properties. A calcination process was also adopted on LDH to increase BSE loading. Physicochemical and mechanical characterizations were performed by spectroscopic (XPS and FTIR), thermogravimetric, rheological, compression test, weight loss and morphological (SEM) investigations. RPLC-ESI-FTMS was employed to investigate the boswellic acids release in simulated synovial fluid. The composites were cytocompatible and capable of supporting the mesenchymal stem cells (hMSC) growth in a 3D-conformation. Loading BSE resulted in the modulation of the pro-inflammatory cascade by down-regulating COX2, PGE2 and IL1β. Chondrogenesis studies demonstrated an enhanced differentiation, leading to the up-regulation of COL 2 and ACAN. This effect was attributed to the efficacy of BSE in reducing the inflammation through PGE2 down-regulation and IL10 up-regulation. Proteomics studies confirmed gene expression findings by revealing an anti-inflammatory protein signature during chondrogenesis of the cells cultivated onto loaded specimens. Concluding, BSE-loaded composites hold promise as a tool for the in-situ modulation of the inflammatory cascade while preserving cartilage healing. • Hydrogels based on gellan gum and Boswellia serrata extract (BSE) were developed. • BSE was loaded into MgAl-layered double hydroxide (LDH), as-such or calcined, clays. • This composite provides anti-inflammatory properties while enhancing chondrogenesis. • It was demonstrated that BSE was successful in down-regulating pro-inflammatory genes. • Chondrogenesis studies demonstrated an enhanced differentiation. [ABSTRACT FROM AUTHOR]

This study tackles the persistent challenge of producing highly reinforced lignin-rubber composites, emphasizing the transformation of agro-industrial residues into value-added products. To address this challenge, we introduce a novel approach termed "in-situ surface modification utilizing a thermo-chemo-mechanical approach" which incorporates the utilization of biomass-derived kraft lignin and a thermally stable organofunctional surface modifier, specifically (3-aminopropyl) triethoxysilane. The resulting material exhibits unprecedented tensile strength (∼15 MPa) along with ∼300 % elongation at break, while typical gum rubber offers 1–2 MPa tensile strength. Additionally, for the other tensile properties like 100 %, and 200 % tensile modulus, the improvement is 7-fold (∼5.6 MPa) and 10-fold (∼11.3 MPa), respectively. Furthermore, this composite presents a higher degree of reinforcement than a passenger car radial (PCR) tire model compound (tensile strength ∼14.5 MPa, 100 % tensile modulus ∼2.2 MPa, and 200 % tensile modulus ∼5.6 MPa) comprised of silica and polysulfide-based coupling agent, with exactly a similar loading of filler. The dynamic mechanical and stress relaxation behavior of the composites are critically discussed concerning the dispersion of the lignin in the sSBR/BR rubber matrix. The morphological orientation and involved chemical interaction in the presence of a surface modifier are also studied in detail. Tear fatigue analysis using pure shear specimens indicates superior fracture toughness at a lower tearing energy regime compared to silica-filled PCR tire compounds. Overall, this study showcases the potential of lignin-reinforced elastomers, offering a promising route for sustainable engineering materials and commercial viability. [Display omitted] • High mechanical performance of Lignin-rubber composites by thermo-chemo-mechanical mixing. • Better dispersion of the lignin particle in butadiene rubber at higher temperature. • Composite shows ∼15 MPa of tensile strength, like Passenger Car Radial tire compound. • Excellent fracture toughness at low tearing energy regime. • Lignin, an alternative to conventional fillers, especially for the tire applications. [ABSTRACT FROM AUTHOR]

In the realm of thermal management applications, there is a growing need for flexible materials that can efficiently dissipate heat. Polymer composites incorporating two-dimensional (2D) materials offer promising solutions due to their superior thermal and mechanical properties. Tungsten disulfide (WS 2) is an excellent filler candidate for polymer composites due to its superior thermal conductivity, mechanical strength, and electrical properties. Unlike graphene, WS 2 has a tunable bandgap, exhibits higher thermal resistance in inert atmospheres, is an effective lubricant over a wide temperature range of − 190 ° C to over 800 ° C , and offers superior gamma radiation shielding. However, high-density 2D material polymer composite fabrication faces challenges due to the agglomeration tendency and sedimentation of heavy nanomaterials within the polymer matrix. This poor dispersion stability negatively impacts the performance and reliability of the composite. We developed a flexible WS 2 foam-polydimethylsiloxane (PDMS) composite via freeze drying and vacuum-assisted infiltration, which not only overcomes fabrication challenges but also enables unique filler reinforcement foam designs. The thermal conductivity of WS 2 -PDMS foam was 1.57 times higher than that of neat PDMS. These thermal properties were modeled using the Lewis-Nielsen model. In-situ tensile tests were conducted to understand the mechanical reinforcing behavior and failure mechanisms of WS 2 foam, which were further studied using the Gibson and Ashby model. The addition of WS 2 into PDMS resulted in an elastic modulus 1.56 times higher than that of neat PDMS. The composite's mechanical properties were analyzed using the Halpin-Tsai model. These findings highlight the potential of WS 2 -PDMS composites for flexible thermal management applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) and molybdenum disulphide (MoS2), have drawn more and more attention as reinforcement in polymer. However, their large specific surface area and strong van der Waals forces result in serious aggregations in polymer matrix, which restrains the reinforcement effect. In this study, MoS2 nanosheets were in situ synthesised vertically and uniformly on the surface of GO nanosheets with the help of a hexadecyl trimethyl ammonium bromide (CTAB) assisted hydrothermal process to facilitate their dispersion in polylactic acid (PLLA) scaffold manufactured via selective laser sintering (SLS). The experimental results revealed that the 1.5 wt% GO/MoS2 nanocomposite exhibited better dispersion state compared with the 1.5 wt% GO and 1.5 wt% MoS2 in PLLA matrix. Therefore, the PLLA scaffold loading 1.5 wt% GO/MoS2 presented 10.2 and 1461 MPa of tensile strength and modulus with enhancement of 61% and 58%, respectively, compared with the pure PLLA scaffold. The reinforcement mechanisms mainly included crack deflection, crack bridging, crack pinning and pulling out of GO/MoS2. What’s more, the GO/MoS2-PLLA scaffold possessed benign cytocompatibility for cell behaviour, suggesting hopeful applications in bone defect repair.

Highlights: The synthetic strategies of electrospun SiO2 nanofibers with diverse structures and their three-dimensional (3D) assemblies are reviewed in detail. The brittleness-to-flexibility transition of SiO2 nanofibers and the means of mechanical strengthening are discussed. The multifunctional applications of 3D SiO2 nanofibrous aerogels are emphasized, and the challenges and opportunities for their future development are prospected. One-dimensional (1D) SiO2 nanofibers (SNFs), one of the most popular inorganic nanomaterials, have aroused widespread attention because of their excellent chemical stability, as well as unique optical and thermal characteristics. Electrospinning is a straightforward and versatile method to prepare 1D SNFs with programmable structures, manageable dimensions, and modifiable properties, which hold great potential in many cutting-edge applications including aerospace, nanodevice, and energy. In this review, substantial advances in the structural design, controllable synthesis, and multifunctional applications of electrospun SNFs are highlighted. We begin with a brief introduction to the fundamental principles, available raw materials, and typical apparatus of electrospun SNFs. We then discuss the strategies for preparing SNFs with diverse structures in detail, especially stressing the newly emerging three-dimensional SiO2 nanofibrous aerogels. We continue with focus on major breakthroughs about brittleness-to-flexibility transition of SNFs and the means to achieve their mechanical reinforcement. In addition, we showcase recent applications enabled by electrospun SNFs, with particular emphasis on physical protection, health care and water treatment. In the end, we summarize this review and provide some perspectives on the future development direction of electrospun SNFs. [ABSTRACT FROM AUTHOR]

Nanodiamonds are metastable allotropes of carbon. Based on their high hardness, chemical inertness, high thermal conductivity, and wide bandgap, nanodiamonds are widely used in energy and engineering applications in the form of coatings, such as mechanical processing, nuclear engineering, semiconductors, etc., particularly focusing on the reinforcement in mechanical performance, corrosion resistance, heat transfer, and electrical behavior. In mechanical performance, nanodiamond coatings can elevate hardness and wear resistance, improve the efficiency of mechanical components, and concomitantly reduce friction, diminish maintenance costs, particularly under high-load conditions. Concerning chemical inertness and corrosion resistance, nanodiamond coatings are gradually becoming the preferred manufacturing material or surface modification material for equipment in harsh environments. As for heat transfer, the extremely high coefficient of thermal conductivity of nanodiamond coatings makes them one of the main surface modification materials for heat exchange equipment. The increase of nucleation sites results in excellent performance of nanodiamond coatings during the boiling heat transfer stage. Additionally, concerning electrical properties, nanodiamond coatings elevate the efficiency of solar cells and fuel cells, and great performance in electrochemical and electrocatalytic is found. This article will briefly describe the application and mechanism analysis of nanodiamonds in the above-mentioned fields., (© 2024 Wiley‐VCH GmbH.)

Carbon nanofillers, such as carbon nanotubes (CNTs) and graphene (G) sheets, have long held interest for reinforcement of polymer matrices. However, a number of factors, including polymer interaction and nanofiller agglomeration, limited the potential of these carbon nanofillers for polymer reinforcement. Recent research highlights that CNT-G complexes potentially improve the dispersion and interaction of the nanofillers with polymer matrices, such as nylon 6, but the effects on the properties remain poorly examined. This study uses molecular dynamics (MD) simulation with the Polymer Consistent Force Field (PCFF) to examine the effects of uniformly-dispersed CNT, single layer graphene, and CNT-G on the mechanical properties of amorphous nylon 6 nanocomposites. For all nanofillers, bulk modulus remained unaffected by increasing concentrations of carbon nanofiller where values were dependent on the interaction energy/atom of the nanofiller with the polymer matrix. Young's moduli increased linearly with addition of carbon nanofillers, indicating that agglomeration of the nanofillers causes the plateaus seen in experimental research. CNT-G nanofillers significantly improved bulk and Young's moduli of the nylon 6 nanocomposite compared to CNT or graphene. Predicted mechanical property trends agree moderately well with experimental results until agglomeration occurs where discrepancies are attributed to crystallinity effects and nanofiller alignments. [ABSTRACT FROM AUTHOR]

CuCr/Diamond (Dia) composites were fabricated by high-energy ball milling and rapid hot-press sintering. The studied CuCr/Dia composites exhibited excellent mechanical properties, reaching a hardness of 187 HV, an ultimate tensile strength of 1010 MPa. In-situ transition layers of Cr 3 C 2 and Cr 23 C 6 , ranging between 10 and 30 nm, were generated at the Cu/diamond interface. This transition layers significantly enhanced the bonding strength between the diamond and the Cu matrix. The load could be effectively transfer to the diamond particle due to the strong bonding. Additionally, nanoscale sub-structures in the matrix can enhance the composite's strength. The studied composite displayed superior strength compared to other copper matrix composites. These findings could extend the applications of the copper-based composites with ultrahigh strength. • In-situ Cr3C2 and Cr23C6, ranging between 10 and 30 nm, were generated at the Cu/diamond interface. • The studied CuCr/Dia composites exhibited excellent mechanical properties, reaching a hardness of 187 HV, an ultimate tensile strength of 1010 MPa. • The load could be effectively transfer to the diamond particle due to the strong bonding. [ABSTRACT FROM AUTHOR]

The adsorption-induced bridging of polymer chains between adjacent nanoparticles was studied in poly(vinyl acetate)/silica nanocomposites with different polymer molecular weights, interaction strengths, nanoparticle sizes, and silica loading fractions. The polymer bridging contribution is successfully decoupled from the apparent rubbery plateau modulus by subtracting the hydrodynamic and trapped chain entanglement contributions. The bridging modulus depends on the nearest interparticle surface distance through a power-law relation with a universal exponent −3. Polymer molecular weight can enhance the bridging modulus only when nanoparticles have a high density of adsorption sites due to the emergence of direct bridging of multiple particles by one chain in addition to the regular bridging through self-similar carpets. Our results illustrate that bridging chains can dominate modulus enhancement at nanoparticle's loading at about 10 vol% in polymer nanocomposites with long polymer chains and high surface silanol density. for Table of Contents use only. [Display omitted] • The effect of matrix polymer chain lengths, nanoparticle sizes, and nanoparticle loadings in polymer nanocomposites on mechanical reinforcement was studied. • The polymer bridging contribution is successfully decoupled from the apparent rubbery plateau modulus. • The molecular origin of the polymer bridging contribution to rubbery plateau modulus in polymer nanocomposites is identified. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) buckypaper has shown extraordinary promise for freestanding supercapacitor electrode, but is usually limited by its extremely poor mechanical performance, which is due to the discrete nature of CNTs and rather low packing density. Meanwhile, manipulating the trade‐off between mechanical and electrochemical properties has not yet been realized for buckypaper electrode. Herein, a major breakthrough in optimizing the trade‐off between mechanical performance and compact capacitive delivery for porous buckypaper electrode is demonstrated by using aramid nanofibers (ANFs). Tailoring the microstructure of buckypaper framework by ANFs achieves 6.5‐ and 24.4‐times improvements in strength and toughness, respectively, without significantly sacrificing the volumetric capacitance (only 15.1% decline). Realizing such optimal integration of mechanical and capacitive properties represents a substantial step towards the practically feasible CNTs‐based structural electrodes. Further loading MnO2 conformal coating enables the freestanding electrode to deliver a superior volumetric capacitance of 155.5 F cm−3 while retaining the robust mechanical performance, which is impossible for conventional buckypaper or CNTs‐based bulk electrodes. The maximized structure‐function relationship achieved in this work validates the feasibility of reinforcing buckypaper electrode by ANFs, which may revolutionize the fabrication of advanced CNTs‐based supercapacitor electrodes, and offer a bright avenue for designing multifunctional structural composites. [ABSTRACT FROM AUTHOR]

The following manuscript presents a comprehensive investigation regarding the influence of electrospinning parameters on fiber quality and mechanical properties of nanofibrous poly(amino acid) meshes. At first, we examine parameters including: solvent options, polymer concentrations, collector speed and distance, voltage, needle sizes and flow rates to prepare fibrous scaffolds based on polysuccinimide. The main objective was to attempt and decrease the fiber diameter as much as possible while not reducing the fiber quality. After that mechanical properties of the meshes were investigated, we demonstrate two possible methods to reinforce them: mechanically induced alignment of the fibers and multilayer compression. Characterization methods include a solubility study, viscosity and conductivity measurements, ATR‐FTIR spectroscopy, scanning electron microscopy, and mechanical uniaxial test. Fiber size was successfully reduced from 615 to 280 nm without any quality aberrations. Mechanical performance not only improved almost three‐fold, but was also enhanced in two directions due to the multilayer composition. With these optimizations, the PSI mesh now possess favorable features for biomedical application according to the relevant literature. [ABSTRACT FROM AUTHOR]

In this study, mechanical and thermomechanical properties of porous silicone composites with various contents of hollow silica particles, treated by vinyltrimethoxysilane (VTMS) as a silane coupling agent, were investigated using tensile and dynamic mechanical analysis. Series of silicone composites with non-modified hollow silica particles as a reference were also prepared for comparative study. The surface characteristics of VTMS-modified hollow silica particles were analyzed using FT-IR spectroscopy. The vinyl function groups on VTMS-modified hollow silica particles led to a chemical bonding to silicone matrix, resulting in reinforcing the mechanical properties of the silicone composites. Tensile modulus of porous silicone composites without the surface modification of silica particles could be predicted by Einstein and Guth/Gold equations, implying the hydrodynamic reinforcement contribution. On the other hand, considerable improvement in the tensile modulus of silicone composites was achieved by strong interfacial adhesion created by chemical bonding on the surface of VTMS-modified hollow silica particles. [ABSTRACT FROM AUTHOR]

This present study centers sensitively on the determination of the effect of natural turkey feather fibers (TFFs) loading on fundamental features (thermal, mechanical, water-uptake, and micro-structural) of thermoplastic polyurethane (TPU). The composites with different TFFs contents (3, 6, 9, and 12 wt.%) were fabricated by the melt blending method using the twin screw extruder and micro-injection molder. The samples were characterized by means of differential scanning calorimeter (DSC), universal mechanical (tensile and hardness) tester, water-uptake, and scanning electron microscope (SEM) techniques. The thermal analysis depicted that the melting temperatures of the soft and hard segments as well as the crystallinity degree of TPU increased consistently with the increase of TFFs loading level thanks to the formation of better close-packed TPU chains in the matrices. As for the mechanical test results, when compared neat TPU, the tensile strengths were reinforced by 26.8% and 19.7%, and the modulus increased by 6.6% and 45.1% for the composite samples including 3% and 6% of TFFs, respectively. However, drastic diminishment were observed at further contents. Additionally, TFFs loadings brought about gradual increase in the water-uptake capacities of the composites due to the increasing of the number of voids and omnipresent flaws in TPU matrices. The taken SEM images also revealed that, at low contents, there existed the enrichment of interfacial adhesion between TFFs and TPU matrix, whereas the morphological appearance of the composites get worse at high contents accompanied by the formation of micro-structural defects. [ABSTRACT FROM AUTHOR]

Dental resin composites are universal restorative materials, and various kinds of fillers are used to reinforce their mechanical properties. However, a combined study on the microscale and macroscale mechanical properties of dental resin composites is missing, and the reinforcing mechanism of the composites is still not fully clarified. In this work, the effects of the nano-silica particle on the mechanical properties of dental resin composites were studied by combined dynamic nanoindentation tests and macroscale tensile tests. The reinforcing mechanism of the composites was explored by combining near-infrared spectroscopy, scanning electron microscope, and atomic force microscope characterizations. It was found that the tensile modulus increased from 2.47 GPa to 3.17 GPa, and the ultimate tensile strength increased from 36.22 MPa to 51.75 MPa, with the particle contents increasing from 0% to 10%. From the nanoindentation tests, the storage modulus and hardness of the composites increased by 36.27% and 40.90%, respectively. The storage modulus and hardness were also found to increase by 44.11% and 46.46% when the testing frequency increased from 1 Hz to 210 Hz. Moreover, based on a modulus mapping technique, we found a boundary layer in which the modulus gradually decreased from the edge of the nanoparticle to the resin matrix. Finite element modeling was adopted to illustrate the role of this gradient boundary layer in alleviating the shear stress concentration on the filler–matrix interface. The present study validates mechanical reinforcement and provides a potential new insight for understanding the reinforcing mechanism of dental resin composites.

Several studies have been conducted to improve the mechanical and other value-added properties of glass fiber-reinforced epoxy (GFRE) composites by the addition of different fillers. In this work, waste iron filings (WIFs) obtained from the steel industry were incorporated into GFRE composite samples in varying amounts of up to 50% (%w) to improve their mechanical and electrical properties. The results showed that, with increasing WIF loading from 0 w% to 50 w%, the resultant composite density gradually increased from 1.4 to 2.1 g/cm3. Surface hardness, Young’s modulus, and tensile strength also increased significantly with the addition of up to 9 w% of WIF followed by a significant drop with more WIF addition due to agglomeration. Overall, Young’s modulus of the GFRE samples with any WIF content was higher than that of the GFRE composite with no WIF. The elongation at break results showed that the GFRE samples were less ductile upon WIF addition, which decreased from 2% to 0.6% upon loading the composite with 50% WIF. In terms of electrical conductivity, the GFRE samples with WIF content of 15% or more were electrically conductive and their electrical conductivity increased with WIF content. It was clear that more WIF was needed to establish a percolated network in the GFRE composites to render them conductive. The electrical conductivity of the GFRE samples containing 15% WIFs was around 2.9 kS/m and increased to 35 kS/m upon the addition of 50% WIFs. These novel electrically conductive GFRE composites could be promising for structural dynamic monitoring systems in the construction industry. They also support the efforts for the utilization of waste materials towards a circular economy.

Silk has recently attracted considerable interest owing to its versatile properties as a natural fiber, especially in the medical sector. However, the mechanical properties of silk limit its potential applications. In our earlier work, the mechanical performance of silk filaments was enhanced owing to the insertion of cellulose nanofibers (CNFs). Nevertheless, silk filaments must be assembled and twisted to form a continuous yarn. In this study, the mechanical properties of CNF-reinforced silk yarns were evaluated to determine the optimal yarn structure. The evolution of the Young's modulus, ultimate tensile strength, toughness, and elongation at break was assessed as a function of the twist level in comparison with regular silk. The results demonstrated that the most favorable compromise of the mechanical properties was obtained at 1000 twists per meter.

The current work studied the physical modification effects of non-covalent surfactant on the carbon-particle-filled nanocomposite. The selected surfactant named Triton™ X-100 was able to introduce the steric repelling force between the epoxy matrix and carbon fillers with the help of beneficial functional groups, improving their dispersibility and while maintaining the intrinsic conductivity of carbon particles. Subsequent results further demonstrated that the physically modified carbon nanotubes, together with graphene nanoplates, constructed an effective particulate network within the epoxy matrix, which simultaneously provided mechanical reinforcement and conductive improvement to the hybrid nanocomposite system. For example, the hybrid nanocomposite showed maximum enhancements of ~75.1% and ~82.5% for the quasi-static mode-I critical-stress-intensity factor and dynamic compressive strength, respectively, as compared to the neat epoxy counterpart. Additionally, the fine dispersion of modified fillers as a double-edged sword adversely influenced the electrical conductivity of the hybrid nanocomposite because of the decreased contact probability among particles. Even so, by adjusting the modified filler ratio, the conductivity of the hybrid nanocomposite went up to the maximum level of ~10−1–100 S/cm, endowing itself with excellent electro-thermal behavior.