Carbon Black Research Articles

Rheology and Processing of High-Strength Liquid Crystal Polymer Reinforced Thermoplastic Composite Materials

Liquid crystal polymer (LCP) composites are presented as lightweight, high-strength, thermoplastic composites. Fumed silica (FS), carbon black (CB), carbon nanostructures (CNS), and boron nitride (BN) added to the polyphenylene sulfide (PPS) increased the viscosity ratio of the PPS to the LCP. PPS filled with 5 wt.% FS was used to optimize injection molding conditions and had a viscosity ratio ranging from 2 to 13. Increasing fill time to 5 s brought about the highest tensile strength of 99 MPa and modulus of 12.5 GPa, while the tool and melt temperatures imparted no significant effect. Mechanical and thermal properties of select LCP materials processed using molding conditions optimized for the experimental materials are presented. Mechanical properties in the crossflow direction were lower than in the flow direction, which could be overcome with tool design and placement of valve gates to tailor the flow patterns. BN filled composites increased the thermal conductivity to a value of 0.26 W/mK at 16 wt.% loading.

Dicarboxylate cellulose nanofibrils-supported silver nanoparticles as a novel, green, efficient and recyclable catalyst for 4-nitrophenol and dyes reduction

This study reports dicarboxylate cellulose nanofibrils (DCNF) as a novel reducing and supporting agent for producing silver nanoparticles (AgNPs) with high efficiency (63.82 % reduction) and loading (6.88 %) using UV light. Unlike previous research, AgNPs formation with DCNF doesn't involve cellulose oxidation. Instead, it appears to involve a loss of carboxyl groups from DCNF. In comparative studies, pristine CNF (PCNF) and TEMPO-oxidized CNF (TOCNF) were also examined for AgNPs production. The resulting AgNPs from DCNF exhibited a significantly smaller average size (3.9 ± 0.7 nm) compared to those from PCNF (26.9 ± 10.9 nm) and TOCNF (13.5 ± 4.5 nm). Catalytic activity evaluation by the 4-nitrophenol (4-NP) reduction reaction revealed a high rate constant of 8.47× 10−3 s−1 by AgNPs/DCNF, which surpassed AgNPs/TOCNF (1.79 × 10−3 s−1) and AgNPs/PCNF (0.63 × 10−3 s−1) by 4.7 and 13.4 times, respectively. Besides 4-NP, AgNPs/DCNF aerogels were also applied for methyl orange and Rhodamine B dyes reduction. The aerogels showed excellent reusability, maintaining over 95 % conversion even after five cycles and also effective in treating real samples and mixed dye solutions. This study opens the door for future research exploring DCNF as a support material for various metal, metal oxide, and carbon nanoparticles.

Rigid Ligand Confined Synthesis of Carbon Supported Dimeric Fe Sites with High-Performance Oxygen Reduction Reaction Activity for Quasi-Solid-State Rechargeable Zn-Air Batteries.

Dimeric metal sites (DiMSs) in carbon-based single atom catalysts (SACs) offer distinct advantages in optimizing the adsorption energies of the catalytic intermediates and reaction pathways over single atom sites, which inspires the investigations on the rational design of DiMSs-based SACs and the accurate discernment of catalytic mechanisms. Here, dimeric Fe sites on carbon blacks (DiFe-N/CBs) are prepared using the precursor of metal-organic complex with a controlled structure, and the rigid ligand confinement secures the preservation of dimeric Fe sites during the thermal treatment. DiFe-N/CBs shows excellent electrocatalytic performance for oxygen reduction reaction (ORR) with a high half-wave potential of 0.917 V, and excellent durability with negligible activity decay. Theoretical studies reveal that the dimeric Fe sites have an optimal adsorption of OOH* with the Yeager-type binding, illustrating the advantages of DiMSs over SAs in catalyzing ORR. The rechargeable aqueous and quasi-solid-state Zn-air batteries assembled using DiFe-N/CBs-based air cathodes achieve small voltage gaps after long term charge/discharge test, showing great promises for practical applications. This synthetic strategy serves a novel platform to produce a scope of catalysts incorporating multimeric metal sites, and studies on the catalytic mechanism lay the foundation for establishing cooperative effect for multidentate adsorption reactions.

Rigid Ligand Confined Synthesis of Carbon Supported Dimeric Fe Sites with High‐Performance Oxygen Reduction Reaction Activity for Quasi‐Solid‐State Rechargeable Zn‐Air Batteries

AbstractDimeric metal sites (DiMSs) in carbon‐based single atom catalysts (SACs) offer distinct advantages in optimizing the adsorption energies of the catalytic intermediates and reaction pathways over single atom sites, which inspires the investigations on the rational design of DiMSs‐based SACs and the accurate discernment of catalytic mechanisms. Here, dimeric Fe sites on carbon blacks (DiFe‐N/CBs) are prepared using the precursor of metal‐organic complex with a controlled structure, and the rigid ligand confinement secures the preservation of dimeric Fe sites during the thermal treatment. DiFe‐N/CBs shows excellent electrocatalytic performance for oxygen reduction reaction (ORR) with a high half‐wave potential of 0.917 V, and excellent durability with negligible activity decay. Theoretical studies reveal that the dimeric Fe sites have an optimal adsorption of OOH* with the Yeager‐type binding, illustrating the advantages of DiMSs over SAs in catalyzing ORR. The rechargeable aqueous and quasi‐solid‐state Zn‐air batteries assembled using DiFe‐N/CBs‐based air cathodes achieve small voltage gaps after long term charge/discharge test, showing great promises for practical applications. This synthetic strategy serves a novel platform to produce a scope of catalysts incorporating multimeric metal sites, and studies on the catalytic mechanism lay the foundation for establishing cooperative effect for multidentate adsorption reactions.

ELECTRICAL CONDUCTIVITY OF RUBBER COMPOUNDS: REVISITING THE INFLUENCE OF FUNDAMENTAL CARBON BLACK PROPERTIES

ABSTRACT Carbon blacks are electrically conductive; however, when carbon black is used as particulate reinforcement in a rubber compound, the compound electrical conductivity can vary from insulative to fully conductive depending on the loading level and properties of the carbon black. An investigation of the influence of three fundamental properties of carbon black—particle size, structure, and porosity—on rubber compound electrical conductivity was conducted. The deconvolution of these three parameters within the study allows for conclusive results to be drawn on what drives compound electrical conductivity and the underlying principles. The work is split into two parts: (1) a determination of the influence of particle size and structure and (2) the influence of porosity. Particle size traces its influence back to numerous particles are in a given volume of rubber compound. Structure’s influence on electrical conductivity varies with the particle size of the carbon black and is for the first time traced back to the aspect ratio of the aggregates. Porosity is separated as a variable in this work by introducing discrete levels of porosity to nascent carbon blacks via gasification. The results show that the impact of carbon black porosity on electrical conductivity in rubber compounds arises from a change in its envelope density and is not due to any change in the inherent aggregate conductivity.

Strain Sensing Enhancement of 3D-printed Polyurethane through Surface Deposition of Carbon Black

Strain sensors for wearable electronics function by identifying mechanical deformations and translating into electrical signals. For optimal performance, electrical conductivity, electrical sensitivity, and flexibility are major properties of strain sensors. Polyurethane (PU) shows promise for custom strain sensors due to its high flexibility. Additionally, using digital light processing (DLP) 3D printing to shape PU is suitable for detecting body movements. Therefore, the aim of this study is developing 3D-printed PU to strain sensing devices, utilizing the surface coating method on 3D-printed PU with carbon black (CB) and polydimethylsiloxane (PDMS) to fabricate the (PDMS+CB)/CB/PU strain sensor. The conductive network of CB enhances sensitivity, while PDMS is incorporated to act as an adhesive for the durability of CB on the PU surface. The results of the experiment reveal a gauge factor of 6.04 with range from 1 to 10% elongation. The strain sensor of this study has high potential to use for strain sensing technology and is capable of detecting small body movements.

Application of micro and nano modifying additives in road construction materials

The need for stronger and more sustainable road infrastructure has stimulated research into innovative materials, including micro- and nano-additives, to improve the performance of asphalt and bitumen. This paper aims to summarize the advances in the application of these additives with a focus on improving mechanical, thermal, and environmental properties. The study provides a detailed review of traditional micro-additives such as elastomers and resins, as well as advanced nanomaterials including nano silica, nano clay, and carbon nanoparticles. Methods include analyzing experimental data from recent studies on bitumen modification with biopolymeric materials such as polylactic acid (PLA), which show an increase in molecular weight, softening point, and ductility. The main results show that the use of nano additives improves the durability of the road surface, increases its resistance to cracking, and increases the service life of the material under different climatic conditions. For example, roads modified with nano silica showed a 20-30% improvement in tensile strength and a 15% reduction in deformation. In addition, PLA bitumen modification increased the softening point by 10°C and improved the overall elasticity by 25%. These results emphasize the potential of micro- and nano-additives to create more durable, environmentally friendly, high-performance road materials.

Targeted Delivery of Celastrol by GA-Modified Liposomal Calcium Carbonate Nanoparticles to Enhance Antitumor Efficacy Against Breast Cancer

Background/Objectives: Breast cancer, a leading health threat affecting millions worldwide, requires effective therapeutic interventions. Celastrol (CEL), despite its antitumor potential, is limited by poor solubility and stability. This study aimed to enhance CEL’s efficacy by encapsulating it within glycyrrhizic acid (GA)-modified lipid calcium carbonate (LCC) nanoparticles for targeted breast cancer therapy. Methods: The 4T1 mouse breast cancer cells were used for the study. GA-LCC-CEL nanoparticles were prepared using a gas diffusion method and a thin-film dispersion method. GA-LCC-CEL were characterized using the zeta-potential, dynamic light scattering and transmission electron microscope (TEM). The in vitro release behavior of nanoparticles was assessed using the in vitro dialysis diffusion method. Cellular uptake was examined using flow cytometry and confocal microscopy. Intracellular ROS and Rhodamine 123 levels were observed under fluorescence microscopy. MTT and colony formation assays assessed cytotoxicity and proliferation, and apoptosis was analyzed by Annexin V-FITC/PI staining. Wound healing and transwell assays evaluated migration, and Western blotting confirmed protein expression changes related to apoptosis and migration. Results: GA-LCC-CEL nanoparticles displayed a well-defined core-shell structure with a uniform size distribution. They showed enhanced anti-proliferative and pro-apoptotic effects against 4T1 cells and significantly reduced breast cancer cell invasion and migration. Additionally, GA-LCC-CEL modulated epithelial-mesenchymal transition (EMT) protein expression, downregulating Snail and ZEB1, and upregulating E-cadherin. Conclusions: GA-LCC-CEL nanoparticles represent a promising targeted drug delivery approach for breast cancer, enhancing CEL’s antitumor efficacy and potentially inhibiting cancer progression by modulating EMT-related proteins.

Enhanced performance of Sr2Fe1.5Mo0.5O6-δ electrode by infiltrating dual functional barium carbonate nanoparticles in symmetrical SOFCs

Enhanced performance of Sr2Fe1.5Mo0.5O6-δ electrode by infiltrating dual functional barium carbonate nanoparticles in symmetrical SOFCs

Features of the Synthesis of Few-Layer Phosphorene Structures During Plasma Electrochemical Cleavage of Black Phosphorus

A comparative study of the emission spectra of cathode electrolysis plasma during plasma electrochemical cleavage of black phosphorus and graphite under maximally identical experimental conditions has been carried out. A significantly lower concentration of active intermediates (OH radicals and O atoms) in the electrolysis plasma during the cleavafe of black phosphorus was found compared with a graphite electrode. It is assumed that this effect is due to a significantly higher rate of interaction of these intermediates with synthesized phosphorene structures than with graphene-like particles. This is confirmed by the detection of a much higher oxygen content in the products of black phosphorus cleavage than in synthesized carbon nanoparticles.

Carbon Nanoparticle Oxidation by NO2 and O2: Chemical Kinetics and Reaction Pathways

Carbon nanoparticle interactions with gases are central to many environmental and technical processes, but the underlying reaction kinetics and mechanisms are not well understood. Here, we investigate the oxidation and gasification of carbon nanoparticles by NO2 and O2 under combustion exhaust conditions. We build on a comprehensive experimental data set and use a kinetic multilayer model (KM‐GAP‐CARBON) to trace the uptake and release of gas molecules alongside the temporal evolution of particle size and surface composition. The experimental results are captured by a model mechanism that involves different types of carbon atoms (edge/plane‐like) and the formation of a reactive oxygen intermediate (activated CO complex) as the rate‐limiting step. A transition between distinct chemical regimes driven by NO2 at lower temperatures and O2 at higher temperatures is reflected by an increase in the observable activation energy from ~60 kJ/mol to ~130 kJ/mol. We derive energy profiles for three alternative reaction pathways that involve uni‐ or bimolecular decomposition of reactive oxygen intermediates.

Carbon Nanoparticle Oxidation by NO2and O2: Chemical Kinetics andReaction Pathways.

Carbon nanoparticle interactions with gases are central to many environmental and technical processes, but the underlying reaction kinetics and mechanisms are not well understood. Here, we investigate the oxidation and gasification of carbon nanoparticles by NO2and O2under combustion exhaust conditions. We build on a comprehensive experimental data set and use a kinetic multilayer model (KM-GAP-CARBON) to trace the uptake and release of gas molecules alongside the temporal evolution of particle size and surface composition. The experimental results are captured by a model mechanism that involves different types of carbon atoms (edge/plane-like) and the formation of a reactive oxygen intermediate (activated CO complex) as the rate-limiting step. A transition between distinct chemical regimes driven by NO2at lower temperatures and O2at higher temperatures is reflected by an increase in the observable activation energy from ~60 kJ/mol to ~130 kJ/mol. We derive energy profiles for three alternative reaction pathways that involve uni- or bimolecular decomposition of reactive oxygen intermediates.

Environmentally Benign Synthesis of Magnetic Fe3O4 Nanoparticle/Carbon Black/Copper‐Quercetin Rods for Sensitive, Disposable Electrochemical Sensor for Mitoxantrone

AbstractPhenolic compounds have a variety of activities but are most famous for their antioxidant and metal‐chelating properties. We explore the green synthesis and application of Fe3O4 nanoparticles, carbon black (CB), and copper‐quercetin (Cu−Q) composite for a disposable electrochemical sensor for mitoxantrone. Fe3O4 was synthesised using Camellia sinensis leaf extract. The copper‐quercetin was synthesised by titrating copper acetate solution with quercetin monohydrate solution at room temperature. Equal amounts of Fe3O4, CB, and Cu−Q were mixed to form Fe3O4‐CB/Cu−Q. The Fe3O4‐CB/Cu−Q/SPE has the lowest detection limit (55.47 pM) compared to previous mitoxantrone sensors. The average recovery was 102.2 %, with an RSD of 4.67 % in serum. The sensor maintained an average accuracy of 98.99 % in the presence of the interfering agent. The detection limit of the new sensor is about five times lower than that of the previous Fe3O4 and carbon black electrode. Therefore, it can be suggested that the Copper‐quercetin complex contributed significantly to the electrode's sensitivity. This research is the first to report the three oxidation potentials for mitoxantrone consistent with mitoxantrone's complex oxidation mechanism. Also, this is the first report on using copper‐quercetin as an electrode material for electrode chemical detection. Furthermore, this is the first green‐derived sensor for mitoxantrone.

Optical Characterization of Fluorescent Chitosan-Based Carbon Dots Embedded in Aqueous Natural Dye

(1) Background: This work evaluated the optical characterization of aqueous fluorescent chitosan-based carbon dots (or carbon nanoparticles CNPs) embedded in natural dye for potential functional packaging applications. Chitosan-based materials are nontoxic, biodegradable, biocompatible, bactericidal, and produced from renewable polymer sources. Anthocyanins are pigments of different colors with a large range of potential applications, such as in bioindicators and biomonitoring; (2) Methods: The CNPs were synthetized in aqueous solutions using chitosan as a carbon source. The natural dye was extracted from the leaves of Tradescantia pallida Purpurea in aqueous solutions. The fluorescence quantum efficiency (η) and fluorescence lifetime (τ) were determined using the mode-mismatched pump–probe thermal lens (TL) technique and time-resolved fluorescence lifetimes (TRFL) measurements, respectively; (3) Results: The η and τ were measured for CNPs embedded in natural dye solution at different concentrations (5.2, 12.09, and 21.57 mass percentage composition). The η and τ photophysical parameters obtained for CNPs embedded in natural dye were compared with those of other CNPs synthesized using different carbon sources, such as leaves, seeds, and protein; (4) Conclusions: Fluorescence spectra and time-resolved fluorescence measurements corroborate the TL results, and relatively high values of η were obtained for the CNP synthesized and embedded in natural dye.

PTFE-based antistatic coatings by incorporating modified carbon black

A kind of antistatic coatings which were applied to nonconductive surfaces were prepared with Polytetrafluoroethylene (PTFE) as matrix, modified carbon black (CB) as conductive filler. Compared to sodium dodecyl sulfate, poly(vinyl pyrrolidone), the TMN-10 modified CB has better wettability, dispersion, stability and re-disperse. When CBTMN-10content is 5 wt.%, the surface resistivity of coating reach to 106Ω*cm, which denotes the coating performance good antistatic behavior. The antistatic coating of 5 wt.% CBTMN-10content is found to exhibit excellent hydrophobicity and high HV hardness. Meanwhile, the low average friction coefficients and wear rate were achieved in antistatic coating of 5 wt.% CBTMN-10content. Furthermore, compared to MXene, reduced graphene oxide, carbon nanotube, the modified CB as conductive material in PTFE antistatic materials could be an useful way not only excellent properties but also large-scale production as well as a reduction in unit cost in antistatic materials.

Inhibitory effects of chlorhexidine-loaded calcium carbonate nanoparticles against dental implant infections

This study aimed to design sustained released biodegradable calcium carbonate nanoparticles loaded with chlorhexidine (CHX-loaded NPs) and to investigate the early osteogenic differentiation and antimicrobial effects on the important bacteria involved in infections of dental implants. The microemulsion method was used to prepare the calcium carbonate nanoparticles loaded with chlorhexidine. The prepared nanoparticles were characterized using conventional methods. The release pattern determination and the biodegradation test were performed for the prepared nanoparticles. For the early osteogenic differentiation test of the prepared nanoparticles, alkaline phosphatase (ALP) activity was detected in human dental pulp stem cells (HDPSCs). The antimicrobial effects of the nanoparticles were evaluated against Escherichia coli, Streptococcus mutans, Enterococcus faecalis, Staphylococcus aureus, and Pseudomonas aeruginosa. The sizes of free calcium carbonate nanoparticles and CHX-loaded NPs were 105 ± 1.63 and 118 ± 1.47 nm and their zeta potentials were − 27 and − 36, respectively. A 50% degradation of nanoparticles was achieved after 100 days. These nanoparticles showed a two-stage sustained release pattern in vitro. Microscopic images revealed that the morphology of free calcium carbonate nanoparticles primarily took on a spherical calcite form, while CHX-loaded NPs predominantly exhibited a cauliflower-like vaterite polymorph. The nanoparticles increased the activity of ALP in cells in two weeks significantly (p < 0.05). Antimicrobial and antibiofilm results showed an efficient effect of the prepared nanoparticle against the studied bacteria. Calcium carbonate nanoparticles are an efficient multifunctional vector for chlorhexidine and can be used as a bioactive antibacterial agent against various oral microorganisms to prevent implant infections.

A piezoresistive dielectric elastomer switch consisting of inkjet-printed carbon black

The piezoresistive effect is a key physical property utilized in soft and stretchable electronics, functioning as intrinsic electromechanical sensors. However, most conventional piezoresistive sensors can only passively measure and quantify external stimuli. To address these limitations, this work integrates an inkjet-printed piezoresistive pattern and a dielectric elastomer actuator (DEA) into a single monolithic dielectric elastomer film, creating a dielectric elastomer switch (DES). This DES can realize dramatic resistance changes along with DEA actuation, leveraging DEA-driven piezoresistivity for active and effective circuit control and signal processing. Theoretically, the DES operates by exhibiting resistance change through the periodic compression induced by DEA actuation. Experimentally, the piezoresistive pattern and the DEA electrodes were fabricated on an acrylic dielectric elastomer (VHB) using inkjet-printed piezoresistive carbon black (CB) and manually brushed conductive grease, respectively. The optimized DES demonstrated approximately 3.77 (±0.11) orders of magnitude in resistance change at a DEA frequency of 0.1 Hz. Compared to previously reported methods (smearing and stamping), inkjet-printed CB patterns showed significant improvements. These included negligible Joule heating impact, precise digital fabrication control, larger resistance change (up to 3.77 orders of magnitude), faster response speeds to DEA actuation (∼0.25 s for 3 orders of magnitude in resistance change), and greater durability (operating at 0.5 Hz for 112 min). Scanning electron microscopy (SEM) characterization revealed that these improvements were attributed to a more uniform distribution of conductive “CB islands” and appropriate non-conductive gap size among them. For demonstrating the applications of DES, it was employed for LED control, DEA-based soft gripper control, and as a multiplexer for signal processing.

Percolation network study of highly sensitive buckled elastomeric piezoresistive sensors

Abstract Flexible pressure sensors are needed for future artificial electronic skin applications. Carbon black (CB)-enhanced elastomers are known for their unique conductivity, allowing for special uses in sensor technology. This research analyzes the sensitivity of elastomeric sensors reinforced with CB, under a pre-strained buckle, using a modified percolation network model to enhance performance in sensing applications. The finite element method is employed to analyze the piezoresistive characteristics of the sensors across various thicknesses. The research involves analyzing the strain patterns of buckled piezoresistive sensors when an indenter applies a load, and how this influences the sensors’ resistivity. The mechanical parameter is directly correlated to the sensor sensitivity through the maximum principal strain. The model shows a good agreement with the experimental data. The pressure sensitivity resulting from indenter compressive contact is 0.03 and 0.0061 kPa−1 in the pressure range of 0–1 and 0–5 kPa for wavy and straight 1000 μm buckled sensors, respectively. The results show that the film with 50% taller waves has a 40%–60% narrower pressure sensing ranges. Moreover, results indicate that adding waves to the geometry of the sensor improves the piezoresistive behavior by increasing the relative displacements of edges. Results also reveal more stable performance from fewer waves and a higher working range by thicker sensors.

Targeted axillary dissection using carbon marking for patients with node-positive breast cancer following neoadjuvant therapy (TADCOM): study protocol for a prospective, multicenter, randomized controlled trial

BackgroundNeoadjuvant chemotherapy (NAC) for breast cancer enables pathological complete response (pCR) in patients initially diagnosed with axillary lymph node metastases, potentially obviating the need for axillary lymph node dissection (ALND). Current targeted axillary dissection (TAD) techniques, guided by traditional tissue markers placed prior to NAC, face challenges such as marker loss and high costs. Carbon nanoparticle suspension injection (CNSI) offers a stable and reliable alternative for marking, which could enhance the TAD procedure. This study aims to evaluate the feasibility and accuracy of different TAD strategies using CNSIs and to explore their clinical utility in locally advanced breast cancer.MethodsThis prospective, multicenter, randomized controlled trial will enroll 126 biopsy-proven breast cancer patients with suspicious axillary lymph node metastases (cN1-2a) who achieve ycN0 status following NAC. Participants will be randomized in a 1:1:1 ratio to undergo TAD guided by: [1] conventional tissue clips (CG-TAD); [2] CNSI lymph node marking (CN-LNM); or [3] peritumoral CNSI mapping (PCN-MAP). Primary endpoints include retrieval rate of marked lymph nodes, number of sentinel and marked lymph nodes, concordance rates, and complication rates. Secondary endpoints encompass regional and distant recurrence rates, survival outcomes, surgical duration, postoperative complications, quality of life scores, and margin status in breast-conserving surgery. Statistical analyses will adhere strictly to the CONSORT guidelines.DiscussionThis study aims to evaluate the feasibility and accuracy of CNSI for targeted axillary dissection in breast cancer patients following neoadjuvant chemotherapy and to explore its clinical significance in reducing surgical complications and costs, as well as improving surgical precision.Trial registrationClinicaltrials.gov, NCT04744506, Registered 27 December 2020, Updated 24 September 2024. Protocol Version Ver 1.2, 17/9/2024.

Characterization of the Anisotropic Electrical Properties of Additively Manufactured Structures Made from Electrically Conductive Composites by Material Extrusion.

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.