Carbon Black Particles Research Articles

Molecular dynamics simulation of the impact of the surface topology of carbon black on the mechanical properties of elastomer nanocomposites.

Carbon black has always played a pivotal role in reinforcing elastomers because it remarkably improves the mechanical properties. The reinforcing effect of carbon black is influenced by its grades, which mainly depend on the difference in the structure of the carbon black particles. Despite many traditional experiments on the performance of carbon black composites, there has been less emphasis on reinforcement mechanisms due to the challenges associated with unraveling the intermolecular interactions. In this paper, a coarse grained molecular dynamics simulation was employed to examine the relationship between the morphology of the carbon black particles and the mechanical properties of the elastomer nanocomposites. Specifically, three different morphological carbon black nanoparticle models, including the smooth particle model, rough particle model, and the rough ellipsoid model, were constructed first. We then focused on investigating the changes of the mechanical properties by systematically varying the filling fraction of the carbon black particles, and the strength of the interfacial interaction between the filler and the rubber. The results indicated that the surface roughness and the filler's shape had a significant impact on the mechanical properties of the filled rubber models. The mechanical enhancement effect of the rough ellipsoidal carbon black is around 50-400% higher than that of the smooth carbon black, and the stronger the interfacial interactions, the more pronounced the enhancement. In addition, the rough ellipsoid filled system has low hysteresis, low permanent deformation, and high fatigue resistance. In general, this work explores the strengthening mechanism of carbon black on the elastomer at the molecular level and generates new insight into the design and fabrication of novel reinforcing fillers.

Improvement in electrochemical properties using SiO-C stacking layer composite for the negative electrode of Li-ion batteries

The stacking layer electrode with a carbon black layer adds on a silicon monoxide (SiO) film is developed for lithium-ion batteries. The electrode is composed of a dense amorphous SiO film with a thickness of 70 nm on a stainless substrate, and an aggregate layer of carbon black particles with a diameter of 40 nm. The electrochemical properties show reversible charge–discharge curves, except the 1st charge process. In the reversible reactions, the maximum charge capacity is 2188.8 mAh/g at the current density of 0.1C. The capacity retention rate and Coulomb efficiency are 94 and 99.7 % for 500 cycles, respectively. After the examination, the SiO surface shows cracks and divided into 1 μm scale domains, though the peeling area is less than a few percent. The charge–discharge reactions bring about large volume changes, however the related degradation is suppressed. The electrochemical properties of the as-deposited SiO film electrode shows the maximum charge capacity of 976 mAh/g and the capacity retention rate of 71 % after 50 cycles. The capacity is nearly half of that of the stacking layer electrode, and the cycle performance is slightly degraded.

Bioactive core–shell structure of TiC/TiO2/SrCO3 coating on carbon black particles for bone tissue formation: Fabrication, characterization, and biological functions

AbstractAlthough carbon‐based nanomaterials, such as carbon nanotubes, graphene, and carbon dots, have attracted much attention for bone tissue regeneration and engineering due to the advantages of being lightweight, mechanical stability, and remarkable ability for bone repair, their toxicity and dispersity are the most concern and greatly limiting their clinical uses. In this article, the surface modification of carbon black particles based on core–shell structure design as a promising candidate material for bone tissue engineering applications is presented. TiC/TiO2/SrCO3‐coated carbon black particles were prepared via molten salt synthesis and hydrothermal process at various temperatures to study the effects of temperature on crystal structure, morphologies, surface wettability, and biological functions. Phase composition, morphologies, and elemental distributions were studied by X‐ray diffraction, field‐emission scanning electron microscope, and energy‐dispersive X‐ray spectroscopy, respectively. Cell proliferation, cell viability, alkaline phosphatase (ALP) activity, and calcium deposition were also investigated. The investigation showed that the reaction temperature played an important role in the crystallinity, phase formation, nanotopography, and biological functions of the particles. The particles treated at 250°C offered favored surface properties of roughness, composition, crystallite size, and wettability for cell adhesion, proliferation, ALP activity, and calcium deposition. As a result, these bioactive core–shell particles would be a promising filler material for bone tissue engineering applications.

A Study on Aqueous Dispersing of Carbon Black Nanoparticles Surface-Coated with Styrene Maleic Acid (SMA) Copolymer.

Carbon black (CB) particles tend to aggregate in aqueous solutions, and finding an optimum dispersing condition (e.g., selection of the type of dispersant) is one of the important tasks in related industries. In the present study, three types of styrene maleic acid (SMA) copolymer dispersants were synthesized, labeled respectively 'SMA-1000', 'SMA-2000', and 'SMA-3000', which have 1, 2, and 3 styrene groups in their repeating units. Then, asymmetrical flow field-flow fractionation (AsFlFFF) was employed to measure the particle size distributions of the aqueous CB dispersions. For the particle size analysis of the CB dispersions, dynamic light scattering (DLS) showed relatively lower reproducibility than AsFlFFF. AsFlFFF showed that the use of SMA-3000 yielded a CB dispersion with the most uniform particle size distribution. When the SMA-3000 dispersant was used, the particle size tended to increase after 1 h of milling as the milling time increased, probably due to the re-agglomeration of the particles by excessive milling. The particle size distributions from AsFlFFF were consistent with the colorimetric observations. With the SMA-3000 dispersant, the lowest L∗ value was observed after 1 h of milling. The AsFlFFF and colorimetric analyses suggest that a stable CB dispersion can be obtained by either 3-h of milling with the SMA-2000 or 1-h of milling with the SMA-3000.

Oriented arrangement of carbon black particles achieved via in situ polymerization and microfibrillation process

Effective dispersion and oriented arrangement of filler particles are crucial to improve the efficiency of filler for improving the mechanical and functional performance of fiber materials. However, how to control the alignment of isotropic (spherical) particles in the melt spinning process is still a challenge. In this work, the distribution of carbon black (CB) particles in Polymethyl methacrylate/polyacrylate@modified carbon black (PMMA/PAcr@MCB) composite were investigated. The results show that the effective dispersion and oriented arrangement of CB particles were achieved when CB particles were encapsulated in PAcr microspheres firstly and then blended with PMMA via in situ microfibrillation. This is ascribed to the distribution of CB particles was confined in the PAcr microfibril phase and rearranged into oriented arrangement after stretching process. Compared to neat PMMA, the elongation at break and fracture energy of PMMA/PAcr@MCB were increased by ~380% and 438%, respectively. Theses increasements are attributable to the high aspect ratio and small diameter of PAcr@MCB microfibrils. The findings in this work provide new enlighten to control the alignment of isotropic particles to improve filler efficiency and avoid big aggregation for preparing materials like fine fibers or thin films.

Multicomponent Comminution within a Stirred Media Mill and Its Application for Processing a Lithium-Ion Battery Slurry

This study presents an approach for targeted comminution of component mixtures within a wet-operated stirred media mill. In the first step, a general understanding of the interactions between individual components on the grinding result with mixtures could be gained with basic experiments and following our former research work. In particular, a protective effect of the coarser particles on the fines could be elucidated. These findings were used to develop a process for the production of a battery slurry containing fine ground silicon particles as well as dispersed carbon black and graphite particles. By a tailored sample preparation applying a combination of particle dissolution and separation, the particle size distributions of carbon black and graphite particles were analyzed separately within the produced battery slurries. Based on the selective particle size analysis, the slurry preparation could be transferred from a complex multistage batch process using a dissolver to a stirred media mill, which was finally operated in a continuous one-passage mode. The prepared slurries were subsequently further processed to silicon-rich anodes using a pilot scale coating and drying plant. Afterward, the produced anodes were electrochemically characterized in full cells. The cell results prove a comparable electrochemical behavior of anode coatings derived from a dissolver- or mill-based slurry production process. Therefore, we could demonstrate that it is possible to integrate the mixing process for the production of multicomponent slurries into the comminution process for the preparation of individual materials upstream. Even with nearly identical starting sizes of their feed materials, the targeted particle size distributions of the single components can be reached, taking into account the different material-dependent particle strengths and sequential addition of single components to the multicomponent comminution process.

Modifying the Network Structures of High Energy Anodes for Lithium‐Ion Batteries through Intensive Dry Mixing

With the ongoing demand for lithium‐ion batteries in the automotive industry, the longevity of the cells is more important than ever. Previous studies on high intensive dry mixing of cathode materials have shown significant changes in product properties across the process chain. Despite a decrease in electrical conductivity, due to the fixation of carbon black particles on the active materials’ surface, electrochemical results have shown more stable long‐term cycling performance of the lithium‐ion battery cells. Despite that, no research studies investigating this process for anode materials have been published yet. Therefore, the effect of an intensive dry mixing process, using a ring shear device and state‐of‐the‐art anode materials, on the slurry, electrode, and cell properties is investigated. The tangential velocity and, therefore, the mechanical stress have been varied, as well as the amount of carbon black in the dry mixing process. The results reveal new insights into material interactions between the binder, carbon black, and the active material that can be purposefully modified. Based on the results, an optimum parameter set is suggested, which not only improves the product characteristics across the process chain, but also increases the long‐term cycling performance of the battery cells significantly.

On-Site Monitoring of Composite Bolted Joints Looseness Using CB/PVP Nanocomposite Piezoresistive Sensor

Bolted joints play important roles in ensuring the integrity of composite structures. Information obtained through structural health monitoring (SHM) can be used to determine the health condition of composite bolted joints. However, integrating monitoring sensors with the composite bolted joints is an extremely challenging problem. In this study, a nanocomposite piezoresistive sensor made of carbon black (CB) and polyvinyl pyrrolidone (PVP) is applied to the composite bolted joints looseness monitoring. The change in the mass fraction of CB particles leads to different resistance values, which are measured to analyze the conductive property of the sensor. The mechanical properties of the sensor are demonstrated under pressure loading with different mass fractions of CB particles. The nanocomposite piezoresistive sensor is integrated with the carbon fiber reinforced plastics (CFRP) single-lap bolted joints, and the optimized electrode layout is presented by comparing the change of resistance and the sensitivity. The state of CFRP bolted joints looseness is represented by the change of relative resistance with different torques. The experimental results show that the CB/PVP nanocomposite piezoresistive sensor has great potential in SHM to realize the integration of the sensor and life-cycle monitoring of composite bolted joints.

On the Application of Carbon Nanomaterials as Modifying Additives in Cement-Based Composites

This article presents the results of a study on the effect of carbon nanosized additives on the structure and properties of cement-based materials. The use of a carbon black dispersion as an alternative to an expensive dispersion of carbon nanotubes is proposed. Based on the experimental data, it is proven that the introduction of carbon black particles into the composition of the cement matrix in an amount of 0.2% by the weight of cement leads to an increase in strength of the cement stone, in both compression and bending, by 21% and 8%, respectively. This increase is compatible with the results obtained when cement matrix was modified with a dispersion of carbon nanotubes.IR spectral and thermal analysis of the modified cement matrix, as well as the study of its microstructure, confirm the formation of a dense net of cement hydration products, including low-basic calcium silicate hydrates and secondary nanosized globular thaumasite formations that contribute to the compaction of the material structure and the following increase in strength.

Effect of Shea butter as plasticizer on natural rubber-carbon black reinforced composites

This paper presents the effect of eco-friendly plasticizer, Shea butter oil (SBO) in rubber compounding involving Carbon black (CB)-filled Natural rubber (NR). The SBO based compounds (SBC) was systematically investigated and the results were compared with compositions prepared with Petroleum-based oil (PO). Although, some of the measured properties were comparable between SBC and POC, however, the SBC generally exhibited better properties compared to the POC. For example, the SBC coded NS5: (NR-50 parts per hundred parts of rubber (phr) CB-5phr SBO) and NS40 (NR-50 phr CB-40 phr SBO) obtained 7 and 17% greater than NT5 (NR-50 phr CB-5phr PO) and NT40 (NR-50 phr CB-40 phr PO), respectively, based on 300 and 100% modulus ratio (M300/M100). In terms of reinforcement measured by bound rubber content, BR (%), NS5 and NS40 recorded higher BR (%) of 9 and 48% than NT5 and NT40, respectively. The NS5 > NT5 by 12 and 7% in terms of crosslinking density and rebound resilience, respectively. Also, the NS5 > NT5 and NS40 > NT40 by 40 and 75%, respectively, in terms of fatigue life behavior. Such enhancement has been linked to successful distribution of the CB particles assisted by SBO within the matrix of NR. While the SBO is economical and has high potential to substitute the PO which is already suspected to be carcinogenic and environmentally unfriendly, SBO has exhibited good plasticizing effect for rubber compounding, especially as curing activators for recipe intended for manufacturing rubber articles.

Toxicokinetic study following intratracheal instillation or oral gavage of two [7Be]-tagged carbon black samples

BackgroundThe toxicokinetic behaviour of nanostructured particles following pulmonary or oral deposition is of great scientific interest. In this toxicokinetic study, following the general principles of OECD TG 417, the systemic availability of carbon black, a nanostructured material consisting of agglomerated aggregates was characterised.MethodsEach of two grades of beryllium-7 labelled carbon black (Monarch® 1000, oxidized and Printex® 90; untreated) was administered either intratracheally or orally to adult rats. Independent of route, rats received a single dose of approximately 0.3 mg radiolabelled carbon black. A total of 12 rats were treated per grade and per exposure route: 4 females each for feces/urine/organs and serial blood kinetics; 4 males for organs. At necropsy, the complete suite of organs was analysed for females, but only the lungs, liver, kidney, reproductive organs for males.ResultsIn the pulmonarily exposed animals, 7Be-Monarch® 1000 and 7Be-Printex® 90 was detected in feces in the first 3 days after treatment at significant levels, i.e. 17.6% and 8.2%, respectively. In urine, small percentages of 6.7% and 0.4% were observed, respectively. In blood, radioactivity, representative of carbon black was within the background noise of the measurement method. At necropsy, 20 days post-instillation, both test items were practically exclusively found in lungs (75.1% and 91.0%, respectively) and in very small amounts (approximately 0.5%) in the lung-associated lymph nodes (LALN). In the other organs/tissues the test item was not detectable. BAL analyses indicated that carbon black particles were completely engulfed by alveolar macrophages.In orally exposed animals, 98% (7Be-Monarch® 1000) and 99% (7Be-Printex® 90) of the measured radioactivity was detected in feces. Excretion was complete within the first 3 days following treatment. 1.3% and 0.5% of measured activity was attributable to urine in animals that received 7Be-Monarch® 1000 and 7Be-Printex® 90, respectively. Radioactivity was absent in blood and other organs and tissues.ConclusionRadioactivity, representative of carbon black, was not detected beyond the experimentally defined limit of quantitation systemically after deposition in lungs or stomach in rats. Under these experimental conditions, the two CB samples were not shown to translocate beyond the lung or the GI tract into the blood compartment.

Enhanced ammonia-rich solution production and electrode separation using magnetic nickel-loaded carbon black in flow-electrode electrochemical deionization (FEED)

Carbon materials with abundant micropores and large specific capacitance (e.g., activated carbon, AC) are usually considered to be ideal candidates for flow-electrode capacitive deionization and are now widely employed to the ammonia recovery from wastewater. However, the microporous structure endows AC with a strong adsorption capacity toward ammonia nitrogen, which greatly reduces the recovery efficiency (the storage of ammonia nitrogen in the electrolyte). In this study, magnetic nickel-loaded carbon black (Ni0-CB) particles were simply synthesized by impregnating Ni onto the surface of the carbon black (CB) particles, endowing no <50 % of electrical energy savings and increasing ammonia recovery efficiency by ~20 % in comparison to AC. When charging, Na+ and NH4+ were migrated to the cathode, with the conversion of NH4+ into NH3 was accelerated due to the higher pH of Ni-CB systems. The excellent electrical conductivity of the CB body and compensation of the conductivity of Ni greatly decreased the electrical energy consumption. Followed by reverse discharge, Na+ and less NH4+ would be turned back into the spacer chamber; the adsorption toward NH3 was effectively reduced due to the abundant mesopores of CB. Thus, NH3 was more likely to be retained in the electrolyte. In addition, the superior magnetic features of Ni-CBs realized the rapid separation of the CB and ammonia-rich solution. The introduction of magnetic Ni-CB in flow-electrode electrochemical deionization technology realized the improved ammonia-rich solution production from wastewater and the recycling of carbon particles without additional solid–liquid separation (i.e., filtration, settlement).

Feasibility of desalination by solar stills for small community scale freshwater demand

Solar stills are conventional desalination systems based on direct solar heating. While their productivity is limited, their simple construction and low maintenance requirements makes them an attractive and feasible option for community-scale desalination. This study shows that low-cost solar stills are capable of producing sufficient freshwater for small disadvantaged communities at costs lower than competing technologies. A variety of solar still materials are investigated showing that the cost of freshwater produced is sensitive to the solar still cost. Inexpensive carbon black particles dispersed in the water are used to increase solar still performance, and a set of low-cost solar still materials are identified from a pool of candidate materials to minimize water production cost by means of optical and energy analyses. In addition, communities with fewer than 10000 residents are identified in the reference region of California to perform an energy analysis to determine freshwater productivity yield and the cost of freshwater production. It is determined that a 10000 m2 solar still could produce freshwater meeting the requirements of small rural communities costing less than $ 7.71 /m3. Attractive investment options are available that could reduce the cost of water produced to less than $ 1.75 /m3. Solar stills were found to be feasible when comparing the cost of freshwater produced with a comparable photovoltaic reverse osmosis system. The proposed methodology can be extrapolated to determine the feasibility of solar still-based desalination systems in other geographical locations. From the results of the analysis, solar stills are proposed for effectively producing low-cost freshwater to increase the accessibility of freshwater in small rural communities.

Electrochemical Metal Recycling: Recovery of Palladium from Solution and In Situ Fabrication of Palladium-Carbon Catalysts via Impact Electrochemistry.

Recycling of critical materials, regeneration of waste, and responsible catalyst manufacture have been repeatedly documented as essential for a sustainable future with respect to the environment and energy production. Electrochemical methods have become increasingly recognized as capable of achieving these goals, and “impact” electrochemistry, with the advantages associated with dynamic nanoelectrodes, has recently emerged as a prime candidate for the recovery of metals from solution. In this report, the nanoimpact technique is used to generate carbon-supported palladium catalysts from low-concentration palladium(II) chloride solutions (i.e., a waste stream mimic) as a proof of concept. Subsequently, the catalytic properties of this material in both synthesis (Suzuki coupling reaction) and electrocatalysis (hydrogen evolution) are demonstrated. Transient reductive impact signals are shown and analyzed at potentials negative of +0.4 V (vs SCE) corresponding to the onset of palladium deposition in traditional voltammetry. Direct evidence of Pd modification was obtained through characterization by environmental scanning electron microscopy/energy-dispersive X-ray spectroscopy, inductively coupled plasma mass spectrometry, X-ray photoelectron spectroscopy, transmission electron microscopy, and thermogravimetric analysis of impacted particles. This showed the formation of deposits of Pd0 partially covering the 50 nm carbon black particles with approximately 14% Pd (wt %) under the conditions used. This material was then used to demonstrate the conversion of iodobenzene into its biphenyl product (confirmed through nuclear magnetic resonance) and the successful production of hydrogen as an electrocatalyst under acidic conditions (under cyclic voltammetry).

Synergetic Effect of Hybrid Conductive Additives for High-Capacity and Excellent Cyclability in Si Anodes.

Silicon is a promising anode material that can increase the theoretical capacity of lithium-ion batteries (LIBs). However, the volume expansion of silicon remains a challenge. In this study, we employed a novel combination of conductive additives to effectively suppress the volume expansion of Si during charging/discharging cycles. Rather than carbon black (CB), which is commonly used in SiO anodes, we introduced single-walled carbon nanotubes (SWCNTs) as a conductive additive. Owing to their high aspect ratio, CNTs enable effective connection of SiO particles, leading to stable electrochemical operation to prevent volume expansion. In addition, we explored a combination of CB and SWCNTs, with results showing a synergetic effect compared to a single-component of SWCNTs, as small-sized CB particles can enhance the interface contact between the conductive additive and SiO particles, whereas SWCNTs have limited contact points. With this hybrid conductive additive, we achieved a stable operation of full-cell LIBs for more than 200 cycles, with a retention rate of 91.1%, whereas conventional CB showed a 74.0% specific capacity retention rate.

Targeting Metal Impurities for the Detection and Quantification of Carbon Black Particles in Water via spICP-MS

Carbon black (CB) is a nanomaterial with numerous industrial applications and high potential for integration into nano-enabled water treatment devices. However, few analytical techniques are capable of measuring CB in water at environmentally relevant concentrations. Therefore, we intended to establish a quantification method for CB with lower detection limits through utilization of trace metal impurities as analytical tracers. Various metal impurities were investigated in six commercial CB materials, and the Monarch 1000 CB was chosen as a model for further testing. The La impurity was chosen as a tracer for spICP-MS analysis based on measured concentration, low detection limits, and lack of polyatomic interferences. CB stability in water and adhesion to the spICP-MS introduction system presented a challenge that was mitigated by the addition of a nonionic surfactant to the matrix. Following optimization, the limit of detection (64 μg/L) and quantification (122 μg/L) for Monarch 1000 CB demonstrated the applicability of this approach to samples expected to contain trace amounts of CB. When compared against gravimetric analysis and UV-visible absorption spectroscopy, spICP-MS quantification exhibited similar sensitivity but with the ability to detect concentrations an order of magnitude lower. Method detection and sensitivity was unaffected when dissolved La was spiked into CB samples at environmentally relevant concentrations. Additionally, a more complex synthetic matrix representative of drinking water caused no appreciable impact to CB quantification. In comparison to existing quantification techniques, this method has achieved competitive sensitivity, a wide working range for quantification, and high selectivity for tracing possible release of CB materials with known metal contents.

Chemical synthesis of metallic silver-based nanopowder catalysts on the conductive carbon black particles as the active materials applied in a Zn-Ag/Zn-air hybrid energy storage system

BackgroundLarge-scale application of renewable energy with energy storage system is important for the decrease in the influence on the environmental problem without any decrease in industrial energy activity. To develop a energy storage system is thus a promising way for further industrial applications. MethodsMetallic based silver catalysts were grown onto the carbon powders in the ethanol bath at the reaction temperature of 70 °C in10 min using a simple chemical synthesis method. Then Ag/carbon powders as the active materials on the nickel (Ni)-foam were applied in the zinc-based energy storage system. Significant findingsX-ray diffraction patterns of samples showed that the catalyst was the metallic silver with the prefer orientation of (1 1 1) crystal plane and the linear sweep voltammograms for samples in 6 M KOH electrolyte showed that the oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) and Ag+↔Ag(s) reaction couples were taking place at sample surface.Our cell with the structure of Zn foil/6 M KOH/Ag@C (weight ratio of 3:1) on the Ni foam showed the charge and discharge voltage of 2.03 and 1.07 V at the charge/discharge current density of 10 mA/cm2, respectively and could be applied in the Zn-based energy storage system.

Sensing mechanism of a flexible strain sensor developed directly using electrospun composite nanofiber yarn with ternary carbon nanomaterials

SummaryRecently, various strain-sensing yarns have been developed without ideal stitchability. Herein, we used spherical carbon black particles (CBs), linear carbon nanotubes (CNTs), and lamellar graphene flakes (GRs) as conductive nanofillers to construct multi-element conductive networks inside a thermoplastic polyurethane (TPU) matrix. First, a highly stretchable and conductive multidimensional carbon-based nanomaterial/TPU composite nanofiber yarn was fabricated using electrospinning, which could be used as a flexible strain sensor without post-processing. Accordingly, the effects of nanomaterials’ dimensionality and synergy on yarns’ conductivity, mechanical properties, and strain sensing performances were explored. The yarn containing multiple networks formed by CB/CNT/GR ternary hybrid networks, CNT and GR auxiliary networks exhibited the best performances. Subsequently, the structural evolution of the ternary conductive network under stretching was revealed to further analyze the sensing mechanism. Finally, the yarn endowed a medicated plaster with an intelligent function to detect motions in the rehabilitation of joint pain by simple sewing.

Development of silver plated electrically conductive elastomers embedded with carbon black particles obtained from Kevlar waste source

The stretchable conductive polymers were fabricated by adding conductive activated carbon fillers to the silicon elastomers and subsequently silver electroplating was performed. To solve the ecological and economical footprint issues the waste of Kevlar fibers were converted into activated carbon particles. The microstructure and porous activated carbon particles were prepared by chemical and physical activation process. The conductive elastomers were prepared into two steps. At first prepared carbon particles were mixed in polymeric silicon elastomer to make it conductive. Hence, the absorbance/adherence of carbon particles was confirmed into elastomer to develop the continuous network to facilitate the electrical conduction. Secondly, further electroplating of silver was performed to make the compact layer on carbon filled polymer. The surface morphology, element analysis and size of activated particles, carbon filled silicon elastomer and electroplated silicon elastomer was observed by SEM, EDX and Zeta size analysis. The FIR analysis was done to analyse the functional groups after the activation of Kevlar web before and after carbonization. Furthermore, the existence of carbon and silver was confirmed by XRD. The electrical resistivity and EMI shielding of elastomer samples was evaluated at different stages (after carbon filling, after silver plating, at stretching state and multiple stretching cycles). The minimum resistivity (12 Ω mm) and maximum EMI shielding (74 dB) was recorded at 0% stretch. While resistivity was increased up to 156 Ω mm at 60% stretch. Furthermore, the thermal stability of develop elastomeric sensors was checked through TGA and Ohmic heating process. At the end, the durability against moisture regain and mechanical action (tensile and hardness) was checked. The prepared elastomers can be used in number of applications including sensors (thermal, humidity control, insulation and electrical conduction). They can also be used as a flexible electrode adjusted with medical devices EMG, ECG and TENs machine.

Optimisation method for carbon black distribution of polypropylene‐based semi‐conductive screen materials and its effect on charge emission behaviour at screen/insulation interface

AbstractThe semi‐conductive (SC) screen materials used in polypropylene (PP)‐based cables are usually multi‐component composites. Polypropylene shows poor compatibility with carbon black (CB), and CB particles tend to disperse in the elastomer phase, which results in CB non‐uniform dispersion in screen materials. The non‐uniform distribution of CB will cause abnormal electric fields at the screen/insulation interface and affect insulation performance. This paper prepared modified PP grafted by molecule maleic anhydride, and four PP‐based SC shielding materials were blended in combination with PP, PP‐g‐MAH, and thermoplastic elastomer (POE) as matrix resin. The CB distribution, electrical conductivity, and basic physical properties of the shielding material were characterised. Different screen materials were served as electrodes to test their effects on the space charge and conductivity characteristics of insulation. The relationship between the macroscopic properties and the distribution characteristics of CB was discussed. Results show that the selective dispersion of CB in screen material was improved by PP‐g‐MAH and the surface electric potential distribution was homogenised. Charge emission at the screen/insulation interface and conductivity can be reduced by homogenising the CB distribution. CB/PP‐g‐MAH/POE prepared in this paper exhibits relatively uniform CB distribution, which can reduce the charge emission from the screen/insulation interface.