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Additive manufacturing (AM) of components using material extrusion (MEX) offers the potential for the integration of functions through the use of multi-material design, such as sensors, actuators, energy storage, and electrical connections. However, there is a significant gap in the availability of electrical composite properties, which is essential for informed design of electrical functional structures in the product development process. This study addresses this gap by systematically evaluating the resistivity (DC, direct current) of 14 commercially available filaments as unprocessed filament feedstock, extruded fibers, and fabricated MEX-structures. The analysis of the MEX-structures considers the influence of anisotropic electrical properties induced by the selective material deposition inherent to MEX. The results demonstrate that composites containing fillers with a high aspect ratio, such as carbon nanotubes (CNT) and graphene, significantly enhance conductivity and improve the reproducibility of MEX structures. Notably, the extrusion of filaments into MEX structures generally leads to an increase in resistivity; however, composites with CNT or graphene exhibit less reduction in conductivity and lower variability compared to those containing only carbon black (CB) or graphite. These findings underscore the importance of filler selection and composition in optimizing the electrical performance of MEX structures. [ABSTRACT FROM AUTHOR]

The ability of bone biomaterials to promote osteogenic differentiation is crucial for the repair and regeneration of osseous tissue. The development of a temporary bone substitute is of major importance in enhancing the growth and differentiation of human-derived stem cells into an osteogenic lineage. In this study, nanocomposite hydrogels composed of gelatin methacryloyl (GelMA), bioactive glass (BG), and multiwall carbon nanotubes (MWCNT) were developed to create a bone biomaterial that mimics the structural and electrically conductive nature of bone that can promote the differentiation of human-derived stem cells. GelMA-BG-MWCNT nanocomposite hydrogels supported mesenchymal stem cells derived from human induced pluripotent stem cells, hereinafter named iMSCs. Cell adhesion was improved upon coating nanocomposite hydrogels with fibronectin and was further enhanced when seeding pre-differentiated iMSCs. Osteogenic differentiation and mature mineralization were promoted in GelMA-BG-MWCNT nanocomposite hydrogels and were most evidently observed in the 70-30-2 hydrogels, which could be due to the stiff topography characteristic from the addition of MWCNT. Overall, the results of this study showed that GelMA-BG-MWCNT nanocomposite hydrogels coated with fibronectin possessed a favorable environment in which pre-differentiated iMSCs could better attach, proliferate, and further mature into an osteogenic lineage, which was crucial for the repair and regeneration of bone. [ABSTRACT FROM AUTHOR]

As microelectronic technology advances, electronic devices have become faster and smaller. The electromagnetic radiation has negative effects on electronic device operation, how to eliminate the electromagnetic radiation has attracted much attention. Copper foil is the most commonly used and effective material for reducing electromagnetic radiation. In practical applications, it is necessary to use adhesive to fix it onto the surface of electronic devices. In this work, an integrated electromagnetic shielding material (AgPs/TPU@Cu hybrid film) was designed and prepared by a facile way, in which the mixture of silver particles (AgPs) and thermoplastic polyurethane (TPU) was cured to form a AgPs/TPU composite film on the surface of copper foil (Cu) by a one-pot heating press processing. The horizontal and vertical electrical resistances of AgPs/TPU composite film decreased to 0.2 Ω and 0.47 Ω at the AgPs loading of 38 wt%, respectively, and the corresponding thermal conductivity reached 0.81 W m−1 K−1. Moreover, the AgPs/TPU@Cu hybrid film at the AgPs loading of 38 wt% exhibited the maximum electromagnetic interference shielding effectiveness (EMI SE) value of 105 dB. This work provides valuable information about EMI shielding technologies for practical electronic applications. [ABSTRACT FROM AUTHOR]

The additive manufacturing of components using material extrusion (MEX) enables the integration of several materials into one component, including functional structures such as electrically conductive structures. This study investigated the influence of the selected additive MEX process on the resistivity of MEX structures. Specimens were produced from filaments and granules of an electrically conductive PLA and filled with carbon nanotubes and carbon black. Specimens were produced with a full-factorial variation of the input variables: extrusion temperature, deposition speed, and production process. The resistivity of the specimens was determined by four-wire measurement. Analysis of the obtained data showed that only the extrusion temperature had a significant influence on the resistivity of the MEX specimens. Furthermore, the impact of the nozzle diameter was evaluated by comparing the results of this study with those of a previous study, with an otherwise equal experimental setup. The nozzle diameter had a significant influence on resistivity and a larger nozzle diameter reduced the mean variance by an order of magnitude. The resistivity was lower for most process parameter sets. As the manufacturing process had no significant influence on the resistivity of MEX structures, it can be selected based on other criteria, e.g., the cost of feedstock. [ABSTRACT FROM AUTHOR]

Ni3(HITP)2 (HITP: 2,3,6,7,10,11-hexaiminotriphenylene) is a very typical 2D electrically conductive metal–organic framework (EC-MOF) material with great promising as active materials in electronic devices. Gas–liquid interface self-assembly is a common method of processing free-standing thin films for this EC-MOF. Owing to the different contact environment during growth process, Ni3(HITP)2 film prepared by gas–liquid interface method has different morphology for up-side surface exposed to air and down-side surface infiltrated in solution. However, the asymmetrical morphology of Ni3(HITP)2 film and its influence on sensing performance have never been implemented. In this work, gas–liquid interface self-assembly method is used to obtain an asymmetrical Ni3(HITP)2 nanofilm in surface morphology with a flat up-side surface and an island-like down-side surface. The surface morphology of as-prepared film has a remarkable influence on the glucose sensing property. The island-like structure for down-side surface film exhibits more excellent glucose sensing performance because of its abundant crystal defect which play an important role in enhancing glucose catalytic oxidation capacity. [ABSTRACT FROM AUTHOR]

Information on the types of fillers used in the composition of epoxy adhesives has been given. Fillers used to ensure electrical conductivity, thermal conductivity, and thixotropy and to reduce fire hazard have been presented. Using VK-9 brand adhesive as an example, the influence of fillers on the strength characteristics of adhesive joints has been shown. The effectiveness of using reinforcing fillers (glass paper, glass veil) in the composition of epoxy film adhesives for structural purposes has been shown. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) of components using material extrusion (MEX) offers the potential for the integration of functions through the use of multi-material design, such as sensors, actuators, energy storage, and electrical connections. However, there is a significant gap in the availability of electrical composite properties, which is essential for informed design of electrical functional structures in the product development process. This study addresses this gap by systematically evaluating the resistivity (DC, direct current) of 14 commercially available filaments as unprocessed filament feedstock, extruded fibers, and fabricated MEX-structures. The analysis of the MEX-structures considers the influence of anisotropic electrical properties induced by the selective material deposition inherent to MEX. The results demonstrate that composites containing fillers with a high aspect ratio, such as carbon nanotubes (CNT) and graphene, significantly enhance conductivity and improve the reproducibility of MEX structures. Notably, the extrusion of filaments into MEX structures generally leads to an increase in resistivity; however, composites with CNT or graphene exhibit less reduction in conductivity and lower variability compared to those containing only carbon black (CB) or graphite. These findings underscore the importance of filler selection and composition in optimizing the electrical performance of MEX structures.

[Display omitted] The air/liquid interface is a superior platform to create nanosheets of materials by promoting spontaneous two-dimensional growth of components. Metal–organic frameworks (MOFs)—intrinsically porous crystals—with π-conjugated triphenylene-based ligands show high electrical conductivities. Forming nanosheets of such conductive MOFs should enable their use in electronic devices. Although highly conductive MOF nanosheets have been created at the air/liquid interface, direct control of their continuity, morphology, thickness, crystallinity, and orientation directly influencing device performance remains as an issue to be addressed. Here, we present detailed insights into the formation process of electrically conductive MOF nanosheets composed of 2,3,6,7,10,11-hexaiminotriphenylene (HITP) and Ni2+ ions (HITP-Ni-NS) at the air/liquid interface. The morphological and structural features of HITP-Ni-NS strongly depend on the standing time—the time without any external actions involved, but leaving the interface undisturbed after setting the ligand solution onto the metal-ion solution. We find that the fundamental features of HITP-Ni-NS are determined by the standing time with conductivity sensitively influenced by such pre-determined HITP-Ni-NS characteristics. These findings will lead towards the establishment of a rational strategy for creating MOF nanosheets at the air/liquid interface with desired properties, thereby accelerating their use in diverse potential applications. [ABSTRACT FROM AUTHOR]

The ability of bone biomaterials to promote osteogenic differentiation is crucial for the repair and regeneration of osseous tissue. The development of a temporary bone substitute is of major importance in enhancing the growth and differentiation of human-derived stem cells into an osteogenic lineage. In this study, nanocomposite hydrogels composed of gelatin methacryloyl (GelMA), bioactive glass (BG), and multiwall carbon nanotubes (MWCNT) were developed to create a bone biomaterial that mimics the structural and electrically conductive nature of bone that can promote the differentiation of human-derived stem cells. GelMA-BG-MWCNT nanocomposite hydrogels supported mesenchymal stem cells derived from human induced pluripotent stem cells, hereinafter named iMSCs. Cell adhesion was improved upon coating nanocomposite hydrogels with fibronectin and was further enhanced when seeding pre-differentiated iMSCs. Osteogenic differentiation and mature mineralization were promoted in GelMA-BG-MWCNT nanocomposite hydrogels and were most evidently observed in the 70-30-2 hydrogels, which could be due to the stiff topography characteristic from the addition of MWCNT. Overall, the results of this study showed that GelMA-BG-MWCNT nanocomposite hydrogels coated with fibronectin possessed a favorable environment in which pre-differentiated iMSCs could better attach, proliferate, and further mature into an osteogenic lineage, which was crucial for the repair and regeneration of bone.

Additive manufacturing of components using the material extrusion (MEX) of thermoplastics enables the integration of multiple materials into a single part. This can include functional structures, such as electrically conductive ones. The resulting functional structure properties depend on the process parameters along the entire manufacturing chain. The aim of this investigation is to determine the influence of process parameters in filament production and additive manufacturing on resistivity. Filament is produced from a commercially available composite of polylactide (PLA) with carbon nanotubes (CNT) and carbon black (CB), while the temperature profile and screw speed were varied. MEX specimens were produced using a full-factorial variation in extrusion temperature, layer height and deposition speed from the most and least conductive in-house-produced filament and the commercially available filament from the same composite. The results show that the temperature profile during filament production influences the resistivity. The commercially available filament has a lower conductivity than the in-house-produced filament, even though the starting feedstock is the same. The process parameters during filament production are the main factors influencing the resistivity of an additively manufactured structure. The MEX process parameters have a minimal influence on the resistivity of the used PLA/CNT/CB composite. [ABSTRACT FROM AUTHOR]

The additive manufacturing of components using material extrusion (MEX) enables the integration of several materials into one component, including functional structures such as electrically conductive structures. This study investigated the influence of the selected additive MEX process on the resistivity of MEX structures. Specimens were produced from filaments and granules of an electrically conductive PLA and filled with carbon nanotubes and carbon black. Specimens were produced with a full-factorial variation of the input variables: extrusion temperature, deposition speed, and production process. The resistivity of the specimens was determined by four-wire measurement. Analysis of the obtained data showed that only the extrusion temperature had a significant influence on the resistivity of the MEX specimens. Furthermore, the impact of the nozzle diameter was evaluated by comparing the results of this study with those of a previous study, with an otherwise equal experimental setup. The nozzle diameter had a significant influence on resistivity and a larger nozzle diameter reduced the mean variance by an order of magnitude. The resistivity was lower for most process parameter sets. As the manufacturing process had no significant influence on the resistivity of MEX structures, it can be selected based on other criteria, e.g., the cost of feedstock.

Additive manufacturing of components using the material extrusion (MEX) of thermoplastics enables the integration of multiple materials into a single part. This can include functional structures, such as electrically conductive ones. The resulting functional structure properties depend on the process parameters along the entire manufacturing chain. The aim of this investigation is to determine the influence of process parameters in filament production and additive manufacturing on resistivity. Filament is produced from a commercially available composite of polylactide (PLA) with carbon nanotubes (CNT) and carbon black (CB), while the temperature profile and screw speed were varied. MEX specimens were produced using a full-factorial variation in extrusion temperature, layer height and deposition speed from the most and least conductive in-house-produced filament and the commercially available filament from the same composite. The results show that the temperature profile during filament production influences the resistivity. The commercially available filament has a lower conductivity than the in-house-produced filament, even though the starting feedstock is the same. The process parameters during filament production are the main factors influencing the resistivity of an additively manufactured structure. The MEX process parameters have a minimal influence on the resistivity of the used PLA/CNT/CB composite.

Electrical conductive properties in cement-based materials have received attention in recent years due to their key role in many innovative application (i.e., energy harvesting, deicing systems, electromagnetic shielding, and self-health monitoring). In this work, we explore the use 3D printing as an alternative method for the preparation of electrical conductive concretes. With this aim, the conductive performance of cement composites with carbon nanofibers (0, 1, 2.5, and 4 wt%) was explored by means of a combination of thermogravimetric analysis (TGA) and dielectric spectroscopy (DS) and compared with that of specimens prepared with the traditional mold method. The combination of TGA and DS gave us a unique insight into the electrical conductive properties, measuring the specimens' performance while monitoring the amount in water confined in the porous network. Experimental evidence of an additional contribution to the electrical conductivity due to sample preparation is provided. In particular, in this work, a strong correlation between water molecules in interconnected pores and the σ (ω) values is shown, originating, mainly, from the use of the 3D printing technique. [ABSTRACT FROM AUTHOR]

Skeletal muscle's combination of three‐dimensional (3D) anisotropy and electrical excitability is critical for enabling normal movement. We previously developed a 3D aligned collagen scaffold incorporating conductive polypyrrole (PPy) particles to recapitulate these key muscle properties and showed that the scaffold facilitated enhanced myotube maturation compared with nonconductive controls. To further optimize this scaffold design, this work assessed the influence of conductive polymer incorporation and scaffold pore architecture on myogenic cell behavior. Conductive PPy and poly(3,4‐ethylenedioxythiophene) (PEDOT) particles were synthesized and mixed into a suspension of type I collagen and chondroitin sulfate prior to directional freeze‐drying to produce anisotropic scaffolds. Energy dispersive spectroscopy revealed homogenous distribution of conductive PEDOT particles throughout the scaffolds that resulted in a threefold increase in electrical conductivity while supporting similar myoblast metabolic activity compared to nonconductive scaffolds. Control of freezing temperature enabled fabrication of PEDOT‐doped scaffolds with a range of pore diameters from 98 to 238 μm. Myoblasts conformed to the anisotropic contact guidance cues independent of pore size to display longitudinal cytoskeletal alignment. The increased specific surface area of the smaller pore scaffolds helped rescue the initial decrease in myoblast metabolic activity observed in larger pore conductive scaffolds while also promoting modestly increased expression levels of the myogenic marker myosin heavy chain (MHC) and gene expression of myoblast determination protein (MyoD). However, cell infiltration to the center of the scaffolds was marginally reduced compared with larger pore variants. Together these data underscore the potential of aligned and PEDOT‐doped collagen scaffolds for promoting myogenic cell organization and differentiation. [ABSTRACT FROM AUTHOR]

Flexible strain sensors have attracted extensive attention due to their potential applications in wearable electronics and health monitoring. However, it is still a challenge to obtain flexible strain sensors with both high stretchability and wide linear strain sensing range. In this study, styrene-ethylene-butadiene-styrene copolymer/carbon nanotubes (SEBS/CNTs) composite fiber which showed both electrical conductivity and high stretchability was fabricated through a scalable wet spinning method. The effect of CNTs content on the strain sensing behavior of the SEBS/CNTs fiber based strain sensor was investigated. The results showed that when the CNTs content reached 7 wt%, the SEBS/CNTs composite fiber was capable of sensing strains as high as 500.20% and showed a wide linear strain sensing range of 0-500.2% with a gauge factor (GF) of 38.57. Combining high stretchability, high linearity and reliable stability, the SEBS/CNTs composite fiber based strain sensor had the ability to monitor the activities of different human body parts including hand, wrist, elbow, shoulder and knee. [ABSTRACT FROM AUTHOR]

This work developed an electrically conductive thermosetting resin composite that transitioned from a liquid to solid without using solvents in response to an increase in temperature. This material has applications as a matrix for carbon fiber reinforced plastics. The composite comprised polyaniline (PANI) together with dodecyl benzene sulfonic acid (DBSA) as a liquid dopant in addition to a radical polymerization system made of triethylene glycol dimethacrylate with a peroxide initiator. In this system, micron-sized non-conductive PANI particles combined with DBSA were dispersed in the form of conductive nano-sized particles or on the molecular level after doping induced by a temperature increase. The thermal doping temperature was successfully lowered by decreasing the PANI particle size via bead milling. Selection of an appropriate peroxide initiator also allowed the radical polymerization temperature to be adjusted such that doping occurred prior to solidification. Optimization of the thermal doping temperature and the increased radical polymerization temperature provided the material with a high electrical conductivity of 1.45 S/cm. [ABSTRACT FROM AUTHOR]

Tannic acid is widely regarded as one of the most promising natural polyphenolic compounds. However, current research predominantly focuses on the utilization of its phenolic hydroxyl groups, with limited exploration of the functional potential of its aromatic structure. Herein, one-dimensional nanofibers based on supramolecular self-assembly were successfully prepared through the simple alkylation reaction of tannic acid and the π-π stacking of aromatic structures. These fibers, with lengths reaching tens of micrometers and an average height of 10 nm, were clearly observed using SEM and AFM. A film with excellent electrical conductivity (σ = 37.9 μS/cm) was fabricated by vacuum filtering the organic suspension of these fibers, which was 100-fold higher than that of the TA film. Additionally, the hydrophobic and lipophilic properties of Bn-TA were further investigated through oil-water separation experiments, where the Bn-TA membrane displayed excellent separation efficiency and durability, maintaining stable performance over multiple cycles. This strategy presents opportunities for the high-value utilization of tannic acid.

Laser-induced graphene (LIG) and its composites have been demonstrated to be useful in broad-reaching applications such as water and air filtration and sensors. A main advantage of LIG is the embedding of conformal graphene foam in any design into polymeric substrates. However, embedded LIG must be detached from the substrate for a composite nanomaterial, and delamination of LIG has been demonstrated. Here, we incorporated LIG as a composite into a double-sided tape using pressure-sensitive adhesives and delamination from the substrate, and demonstrated its use for electro-photo-thermal applications, including bacterial inactivation. LIG was transferred onto thermally conductive pressure-sensitive adhesive containing carbon black, and a double-sided sticky tape was prepared by sandwiching perforated tissue adhesive between two LIG layers, giving enhanced electrical conductivity in the x, y, and z directions compared to commercial carbon tape. The LIG composite tape showed excellent electrothermal properties with a maximum temperature >120 °C at 10 V and a temperature rise >70 °C under 120 mW/cm2 solar irradiation. The same electrothermal activity was observed after 50 heating and cooling cycles and reached a temperature of ∼111 °C. Bacterial inactivation was observed on the surface of the LIG composite tape at ∼3.5 V, and electro- and photothermal effects caused sterilization of the surfaces up to 99.99%. These electrically conductive LIG composite adhesive tapes might be used in electronic applications for heating surfaces at low voltages (<9 V) or to prevent surface biofilm or microbial growth. [Display omitted] • Laser-induced graphene composite tape (LIGC-tape) formed via delamination of LIG. • LIGC-tape showed excellent electrical heating properties at between 1 and 10 V. • Solar surface heating properties between 80 mW/cm2- 120 mW/cm2. • Enhanced bacterial killing due to combined electrical and IR/NIR photo effects. [ABSTRACT FROM AUTHOR]

Flexible strain sensors have attracted extensive attention due to their potential applications in wearable electronics and health monitoring. However, it is still a challenge to obtain flexible strain sensors with both high stretchability and wide linear strain sensing range. In this study, styrene-ethylene-butadiene-styrene copolymer/carbon nanotubes (SEBS/CNTs) composite fiber which showed both electrical conductivity and high stretchability was fabricated through a scalable wet spinning method. The effect of CNTs content on the strain sensing behavior of the SEBS/CNTs fiber based strain sensor was investigated. The results showed that when the CNTs content reached 7 wt%, the SEBS/ CNTs composite fiber was capable of sensing strains as high as 500.20% and showed a wide linear strain sensing range of 0-500.2% with a gauge factor (GF) of 38.57. Combining high stretchability, high linearity and reliable stability, the SEBS/CNTs composite fiber based strain sensor had the ability to monitor the activities of different human body parts including hand, wrist, elbow, shoulder and knee. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI) causes cell death, disrupts electrical activity, triggers arrhythmia, and results in heart failure, whereby 50-60% of MI-associated deaths manifest as sudden cardiac deaths (SCD). The most effective therapy for SCD prevention is implantable cardioverter defibrillators (ICDs). However, ICDs contribute to adverse remodeling and disease progression and do not prevent arrhythmia. This work develops an injectable collagen-PEDOT:PSS (poly(3,4-ethylenedioxythiophene) polystyrene sulfonate) hydrogel that protects infarcted hearts against ventricular tachycardia (VT) and can be combined with human induced pluripotent stem cell (hiPSC)-cardiomyocytes to promote partial cardiac remuscularization. PEDOT:PSS improves collagen gel formation, micromorphology, and conductivity. hiPSC-cardiomyocytes in collagen-PEDOT:PSS hydrogels exhibit near-adult sarcomeric length, improved contractility, enhanced calcium handling, and conduction velocity. RNA-sequencing data indicate enhanced maturation and improved cell-matrix interactions. Injecting collagen-PEDOT:PSS hydrogels in infarcted mouse hearts decreases VT to the levels of healthy hearts. Collectively, collagen-PEDOT:PSS hydrogels offer a versatile platform for treating cardiac injuries., (© 2024 The Authors. Advanced Materials published by Wiley‐VCH GmbH.)

The properties of electrically conductive CsPbBr3 single crystals obtained from the melt have been studied. According to the results of Raman spectra, the covalent bonds in the octahedra [PbBr6] 4− have different strengths in different directions. This bond anisotropy promotes the formation of bromine vacancies located along selected crystallographic directions, which become sites of crystal degradation and the formation of Cs4PbBr6 microformations. A potential barrier at the boundary between the Cs4PbBr6 single crystal and the Cs4PbBr6 microformations was found. [ABSTRACT FROM AUTHOR]

Electrical conductive properties in cement-based materials have received attention in recent years due to their key role in many innovative application (i.e., energy harvesting, deicing systems, electromagnetic shielding, and self-health monitoring). In this work, we explore the use 3D printing as an alternative method for the preparation of electrical conductive concretes. With this aim, the conductive performance of cement composites with carbon nanofibers (0, 1, 2.5, and 4 wt%) was explored by means of a combination of thermogravimetric analysis (TGA) and dielectric spectroscopy (DS) and compared with that of specimens prepared with the traditional mold method. The combination of TGA and DS gave us a unique insight into the electrical conductive properties, measuring the specimens’ performance while monitoring the amount in water confined in the porous network. Experimental evidence of an additional contribution to the electrical conductivity due to sample preparation is provided. In particular, in this work, a strong correlation between water molecules in interconnected pores and the σ(ω) values is shown, originating, mainly, from the use of the 3D printing technique.

This work developed an electrically conductive thermosetting resin composite that transitioned from a liquid to solid without using solvents in response to an increase in temperature. This material has applications as a matrix for carbon fiber reinforced plastics. The composite comprised polyaniline (PANI) together with dodecyl benzene sulfonic acid (DBSA) as a liquid dopant in addition to a radical polymerization system made of triethylene glycol dimethacrylate with a peroxide initiator. In this system, micron-sized non-conductive PANI particles combined with DBSA were dispersed in the form of conductive nano-sized particles or on the molecular level after doping induced by a temperature increase. The thermal doping temperature was successfully lowered by decreasing the PANI particle size via bead milling. Selection of an appropriate peroxide initiator also allowed the radical polymerization temperature to be adjusted such that doping occurred prior to solidification. Optimization of the thermal doping temperature and the increased radical polymerization temperature provided the material with a high electrical conductivity of 1.45 S/cm.

A simple method for the preparation of multifunctional nanocomposite was developed towards the production of water‐repellent, electrically conductive, and photoluminescent film onto cotton fibres. The nanocomposite was composed of lanthanide‐doped strontium aluminium oxide and silicon rubber dispersed in petroleum ether. The electrically conductive fabric was woven from nickel strips twisted with cotton filaments as core yarns, which were wrapped with pure cotton yarns. The nanoparticles (NPs) of lanthanide‐doped strontium aluminium oxide were mixed with environmentally friendly room‐temperature vulcanizing silicon rubber (RTV‐SR) dissolved in petroleum ether to give the silicon rubber/strontium aluminate nanocomposites. The produced nanocomposites were applied onto electrically conductive cotton/nickel fibres using spray‐coating technology. The surface of the cotton/nickel fibres showed different hierarchical morphologies depending on the total content of the silicon rubber. Additionally, the superhydrophobic effect was found to be improved upon increasing the total content of the luminescence pigment NPs. The morphologies of the prepared phosphor NPs were determined using transmission electron microscopy (TEM). The generated transparent luminescence film demonstrated an absorbance peak at 358 nm and an emission peak at 515 nm. Photoluminescence of cotton fibres was monitored with the generation of different colours, including grey, green‐yellow, bright white, and turquoise shades as recognized using CIE Laboratory colorimetric parameters. The emission, excitation, lifetime, and decay time spectra of the phosphorescent spray‐coated cotton samples were studied. The surface morphologies and chemical compositions of the spray‐coated cotton/nickel were investigated using wavelength‐dispersive X‐ray fluorescence (WD‐XRF), scanning electron microscope (SEM), Fourier‐transform infrared spectra (FTIR), and energy‐dispersive X‐ray analyzer (EDAX). The superhydrophobic effects were characterized by measuring static water contact angle. The comfort characteristics of the treated cotton/nickel substrates were assessed by investigating their air permeability and stiffness. The treated cotton/nickel fabrics also displayed an antimicrobial activity. The results displayed water repellence with high electrical conductivity and photoluminescence properties. [ABSTRACT FROM AUTHOR]

Carbon-based nanocomposites featuring enhanced electrical properties have seen increased adoption in applications involving electromagnetic interference shielding and electrostatic dissipation. As the commercialization of these materials grows, a thorough understanding of how thermal activation affects the rheology and electrical performance of CNT–epoxy blends can inform quality decisions throughout the production process. The aim of this work was the identification of the effects that thermal activation has on the electrical and rheological properties of uncured epoxy mixtures and how those may be tied to the resulting cured composites. Herein, three distinct CNT-loaded composite mixtures were characterized for changes in electrical resistivity and viscosity resulting from varying activation times. Electrical conductivity decreased as activation time increased. Uncured mixture viscosity exhibited a strong dependence on CNT loading and applied strain, with activation time being found to significantly reduce the viscosity of the uncured mixture and surface profile of cured composite films. In all cases, cured composites featured improved electrical conductivity over the uncured mixtures. Factors contributing to the observed behavior are discussed. Raman analysis, optical microscopy of CNT networks, and data from silica bead mixing and dispersion studies are presented to contextualize the results.

Purpose. The evaluation of the effect of armature parameters on the efficiency of a linear pulsed electromechanical converter, taking into account the power, speed, constructive and environmental parameters. Methodology. First, the height of the electrically conductive, coil and ferromagnetic armature of a linear pulse electromechanical converter is determined, at which the highest velocity develops. An integral efficiency index is introduced, which takes into account, in a relative way, the power, speed, energy, electrical and field characteristics of the converter. Variants of the efficiency evaluation strategy are used that take into account the priority of each indicator of a linear pulse electromechanical converter using the appropriate weighting factor in the integral efficiency index. Results. A mathematical model of a linear pulsed electromechanical converter is developed. It is established that as the height of the electroconductive, coil and ferromagnetic armature increases, the force pulse increases. The greatest speed develops with the use of a coil armature, and the smallest with an electroconductive armature. In the converter with coil and ferromagnetic armature, practically the same values of the electrodynamic and electromagnetic force pulse are realized, while in the converter the electrodynamic force is 1.52 times smaller in the converter by the electrically conductive armature. It is established that with all efficiency evaluation strategies, the converter with a coil armature is the most effective, even in spite of its constructive complexity, and the converter with a ferromagnetic armature is the least effective, although it is constructively the simplest. Originality. For the first time, using the integral efficiency index, which takes into account the power, speed, energy, electrical and field indices in a relative way, it is established that with all efficiency evaluation strategies, the converter with a coil armature is the most effective, and the converter with a ferromagnetic anchor is the least effective. Practical value. The height of the electrically conductive, coil and ferromagnetic armature of a linear pulse electromechanical converter is determined, at which the highest speed develops. It is shown that when using an electrically conductive armature, the value of the electrodynamic force pulse is lower than when using a coil and ferromagnetic armature. It is established that the converter with a coil armature is the most efficient, and the converter with a ferromagnetic armature is the least effective.

• A superhydrophobic and conductive nanofiber composite (SCNC) is prepared. • The SCNC possesses SiO 2 /graphene shell and polymer nanofiber core. • The SCNC possesses good anti-corrosive performance. • The SCNC strain sensor shows high stretchability, sensitivity and good durability. • The SCNC strain sensor can be used for full range detection of human body motions. It is desirable and still challenging to develop flexible, breathable and anti-corrosive wearable strain sensors with high stretchability and sensitivity that can realize full range body motions. Here, a superhydrophobic and conductive nanofiber composites (SCNCs) with a hierarchical SiO 2 /graphene shell and polyurethane (PU) nanofiber core microstructure were fabricated by assembling graphene on PU nanofibers under the assistance of ultrasonication, followed by stretching-induced SiO 2 nanoparticles decoration onto the graphene shell. The introduction of graphene and SiO 2 nanoparticles improves both Young's modulus, tensile strength and the elongation at break of PU nanofibrous membrane. The superhydrophobicity and conductivity can be almost maintained after the SCNCs are subject to cyclic stretching or abrasion or even exposed to harsh conditions. When used as strain sensors, the SCNCs show high stretchability, reliability and good durability and can be used in harsh environment including acid and salt conditions. The SCNCs are then assembled to monitor full range body motions including both subtle and large body movements, making it a promising candidate in wearable electronics. [ABSTRACT FROM AUTHOR]

Abstract Traditionally, C12A7 materials have been processed via solid-state reaction followed by pulsed laser deposition (PLD) or floating zone (Fz) crystallization methods at high temperature, high cost approaches to single-phase films. These techniques require a significant number of process steps to generate C12A7:e− materials that have been shown to exhibit exceptional electrical conductivities as high as 1 S/cm. We demonstrate here an effective alternative method using flame made C12A7 nanopowders (NPs) produced via liquid-feed flame spray pyrolysis (LF-FSP). Nearly fully dense, single phase, and transparent C12A7 films (< 50 μm) can be produced by processing these NPs into green films by tape-casting, thermo-compression and then sintering to 1300 ℃ /3 h/O 2. Subsequent heat treatments in 20/80 H 2 /N 2 replaces cage trapped O2- ions forming C12A7:H− followed by UV irradiation to generate C12A7:e− with electrical conductivities of 35 mS cm-1. C12A7:e- appears to belong to a new class of transparent conducting oxides (TCOs) that may offer commercial potential on further optimization due to low materials and processing costs, environmental stability, and natural abundance when processed efficiently. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we report on a study of electronically conductive porous TiN ceramics prepared by aqueous gel‐casting. The effects of solid loading, sintering temperature, and sintering aids on the phase composition, microstructure, and volume fraction of porosity of the prepared porous TiN ceramics are studied. The SEM results show that porosity is uniformly distributed in all of the samples studied. With increasing solid loading and sintering temperature, the volume fraction of porosity decreases slowly. Moreover, the relationship between volume fraction of porosity and mechanical and electrical properties has also been investigated. Our results show that adding Y2O3‐TiO2 as combined sintering aids results in a sharp decrease in the volume fraction of porosity, and the volume fraction range changes from 42%‐60% to 28%‐52%. Moreover, adding sintering aids results in an increase in flexural strength and electrical conductivity with a change in maximum value from 34.6 MPa and 2.3 × 104 S∙m−1 to 101.6 MPa and 5.1 × 104 S∙m−1, respectively. [ABSTRACT FROM AUTHOR]

The phenomenon of electro material dislocation consists of two objects electrically conductive at a distance from one another and between which there is an electric potential difference. Suppose two objects (parts) initially at distance and electric potential difference start to be close to each other. Distance that will pierce the dielectric (the environment in which the two parts are air, water, oil) and will begin to show electric discharge between the two parts is called "" gap. "After electrical arcing, a certain amount of matter will be deployed in two parts. tampered If their arc will continue until the distance between the two parts will increase (due to displacement of matter). electro material processing this destructive phenomenon is optimized and exploited in constructively. Introducing two parts (part that is intended to be processed and the tool that will perform the processing - where cars thread wire or electrode in a car with massive electrode) in a dielectric liquid (distilled water or some oil compound) this phenomenon is amplified because the arc that occurs between the tool and work piece by local vaporization of material creates a bubble of gas.

Lightweight and robust carbon nanotube (CNT)/chitosan (CS) foams were assembled by a facile unidirectional freeze-drying method in this work. The CNT/CS foam exhibited an excellent electromagnetic interference (EMI) shielding effectiveness (SE) of 37.6 dB while the density was only 17.6 mg·cm −3 , and thus the corresponding specific SE was up to 8556 dB·cm 2 ·g −1 . The superior EMI shielding performance was mainly attributed to the perfect conductive networks. Additionally, the absorption coefficient of CNT/CS foam was up to 81.73% under high EMI SE of 37.6 dB, which was remarkable among the reported EMI shielding materials with comparable EMI shielding level. More importantly, the addition of CS significantly increased the compressive strength and modulus of CNT/CS foam to 34.1 KPa and 177.1 KPa, which were 84% and 149% higher than those for the pure CNT foam, respectively. These results indicate that the CNT/CS foam is an ideal high-efficient EMI shielding material, which has high potential applications in the fields of aerospace, automotive, and electronic devices. [ABSTRACT FROM AUTHOR]

A flexible and highly conductive nylon porous membrane (NPM)/nickel (Ni) composite film with outstanding electromagnetic interference (EMI) shielding performance is fabricated via a facile electroless deposition method. The NPM, with a large specific surface area, is amenable to the electroless deposition of Ni and the enhancement of interaction between Ni and NPM. Highly conductive Ni layers are uniformly deposited on the upper and lower surfaces of NPM to construct a sandwich structure that provides numerous interfaces to reflect, scatter, and absorb electromagnetic waves. The resultant NPM/Ni film exhibits an ultra-high EMI shielding effectiveness (EMI SE) of 77 dB with a film thickness of only 100 μm. Moreover, the NPM/Ni film shows cyclic EMI shielding stability under repeated mechanical deformation, with 85% retention after 300 bending cycles. Our work provides an effective approach to fabricate reliable metal-polymer composite films that show potential for applications in EMI shielding. [ABSTRACT FROM AUTHOR]

This paper addresses the development of an electrically conductive flexible nanocomposite membrane by the incorporation of an optimum amount of pyrrole into tetraethyl orthosilicate crosslinked poly(vinyl alcohol). The incorporated pyrrole underwent in-situ chemical oxidation in presence of iron(III) chloride. The resulting membrane was subjected to various techniques to understand its physico-chemical properties. The nanocomposite membrane demonstrated an excellent electrical conductivity of 4.56 S cm −1 with a desired flexibility. The electrochemical properties of the electrode membrane were systematically investigated using cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy. The resulting electrode membrane exhibited a specific capacitance as high as 484 F g -1  at a current density of 0.1 A g −1 with an excellent cycle life stability. Based on its excellent electrochemical performance, we have developed both interdigital micro-supercapacitor and sandwich-type supercapacitor devices; among these, the interdigital micro-supercapacitor exhibited a specific capacitance of 51.42 F g -1  at 0.05 A g −1 , which is two times higher than that of sandwich-type supercapacitor (25.49 F g −1 ). Furthermore, the method adopted here for the fabrication of an interdigital micro-supercapacitor device can be easily applied to large-scale fabrication of electrically conductive membranes and opens up new opportunities for flexible lightweight energy storage devices. [ABSTRACT FROM AUTHOR]