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This study investigates the efficiency of already developed surface‐modified carbon black (CB), both independently and in conjunction with nano‐silica, as a hybrid filler, to the properties of natural rubber (NR) compounds. The modification process, followed by coupling agent treatment, enhanced cross‐link density and curing characteristics, though the inclusion of nano‐silica alone negatively affected curing due to its inherent polarity and tendency to agglomerate. The filled compounds with modified CB exhibited significant improvements in mechanical properties, notably tear resistance. Moreover, the combination of nano‐silica with modified CB yielded compounds with superior tear resistance, attributed to synergistic effects. CB surface modification exhibited varying effects on the glass transition temperature, with enhancements observed in tan δ at lower temperatures, indicating improved ice and wet grip potential. Also, it reduced rolling resistance after treatment with a coupling agent. While thermal stability remained consistent across the studied compounds, swelling resistance varies with filler type and ratio. Thermodynamic analysis confirmed the positive impact of CB surface modification on the elasticity and chain mobility of the investigated rubber compounds. It was concluded that the strategic selection of fillers and modification approaches were essential for achieving optimal results in the rubber compound's performance and application. [ABSTRACT FROM AUTHOR]

Methodologies across the dispersion preparation, characterization, and cellular dosimetry of hydrophilic nanoparticles (NPs) have been developed and used extensively in the field of nanotoxicology. However, hydrophobic NPs pose a challenge for dispersion in aqueous culture media using conventional methods that include sonication followed by mixing in the culture medium of interest and cellular dosimetry. In this study, a robust methodology for the preparation of stable dispersions of hydrophobic NPs for cellular studies is developed by introducing continuous energy over time via stirring in the culture medium followed by dispersion characterization and cellular dosimetry. The stirring energy and the presence of proteins in the culture medium result in the formation of a protein corona around the NPs, stabilizing their dispersion, which can be used for in vitro cellular studies. The identification of the optimal stirring time is crucial for achieving dispersion and stability. This is assessed through a comprehensive stability testing protocol employing dynamic light scattering to evaluate the particle size distribution stability and polydispersity. Additionally, the effective density of the NPs is obtained for the stable NP dispersions using the volumetric centrifugation method, while cellular dosimetry calculations are done using available cellular computational modeling, mirroring approaches used for hydrophilic NPs. The robustness of the proposed dispersion approach is showcased using a highly hydrophobic NP model (black carbon NPs) and two culture media, RPMI medium and SABM, that are widely used in cellular studies. The proposed approach for the dispersion of hydrophobic NPs results in stable dispersions in both culture media used here. The NP effective density of 1.03–1.07 g/cm3 measured here for black carbon NPs is close to the culture media density, resulting in slow deposition on the cells over time. So, the present methodology for dispersion and dosimetry of hydrophobic NPs is essential for the design of dose–response studies and overcoming the challenges imposed by slow particle deposition. [ABSTRACT FROM AUTHOR]

This study aims to improve the dispersion of Carbon Black (CB) filled Hydroxyl‐Terminated Polybutadiene (HTPB)‐Isophorone Diisocyanate (IPDI) based polyurethane liner by both adding a dispersant and developing a production process to obtain improved mechanical, rheological, thermal, and adhesion properties. Printex‐U (CB1) and Thermax N‐991 (CB2) carbon blacks were used as fillers. Three different dispersants, which are BYK 9076 (D1), BYK 9077 (D2), and BYK Silclean 3700 (D3) were added to the liner formulation at various amounts. BYK 9076 (D1) was found as the most effective dispersant due to its bifunctional chemical structure. By adding 2 wt.% of BYK 9076 (D1) dispersant to the polyurethane liner comprising 10 wt.% CB1, viscosity was reduced by 45 %, and tensile strength and elongation at break were improved from 1.77 MPa to 1.88 MPa and from 375 % to 385 % respectively. The dispersion of the CB in the polyurethane liner was further improved by the ultrasonication process and tensile strength and elongation at break were increased to 2.03 MPa and 425 %, respectively. This process also contributed to an improved Limiting oxygen index (LOI), elevating it from 20 % to 22 % initially and further by 25 % through ultrasonication. Scanning Electron Microscopy (SEM) verified that the addition of D1 dispersant and ultrasonication effectively reduced CB particle agglomeration. The migration of plasticizer was also assessed over 12 months through bonding testing, TGA, and FTIR analysis. It was noticed that the effective dispersion of CB particles made the liner more resistant to the plasticizer migration. [ABSTRACT FROM AUTHOR]

Copyright of China Rubber Industry is the property of Editorial Office of China Rubber Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays, waste tires have emerged as one of the most significant sources of environmental pollution. To address this issue, pyrolysis has become a widely adopted method. The continuous rotary kiln reactor has particularly gained popularity in industrial production for pyrolysis due to its suitability. In order to guide the development of new industrial continuous rotary kiln reactors and achieve high-performance pyrolytic carbon black (CBp), this study was conducted to investigate the relationship between the physical and chemical characteristics of CBp and pyrolysis temperature. The elevated-temperature procedure led to a reduction in DBP values from 90 to 70 mL/100 mg, accompanied by a rise in the specific surface area from 63 to 77 m2/g. The augmentation of pyrolysis temperature was noted to induce the agglomeration of CBp particles, thereby negatively impacting their dispersion within polymer matrices. CBp particles at 550 °C exhibited greater structural order, as determined by Raman spectroscopy, which can be attributed to the elevated temperature proximate to the cylinder wall surface. Furthermore, the potential of CBp for reinforcement in natural rubber (NR) was taken into consideration. The pronounced propensity of high-temperature CBps to agglomerate led to uneven dispersion within the polymer, consequently causing heightened heat accumulation and the emergence of the Payne effect. Based on a thorough analysis of the outcomes, the optimal pyrolysis temperature for CBp synthesis within the continuous reactor was ascertained. [ABSTRACT FROM AUTHOR]

This study examines hilly terrain's effect on black carbon (BC) dispersion. The apportionment of distinct sources obtained by a two-component mixing model (Aethalometer: AE-33) using improved radiative transfer equations showed the dominance of traffic-derived black carbon (BCFF) emissions in the study region. The AERMOD was used to model BC emissions from moving traffic as a line source and parking lot as area source using observational and WRF-processed meteorology for the winter (January to March 2020). The model results showed that the BC levels substantially vary with local meteorological conditions, traffic volume, and composition. The hilly terrain obstructs the winds and develops a negative pressure loading to a vacuum on the other side of the hills, which promotes the accumulation of emissions, causing high BC concentrations. The pockets of higher concentration were seen at the locations where steep slopes were associated with low winds (<1 m s−1) and hill fogs. The AERMOD model, after statistical evaluation against the observational datasets, has been applied to study the reduction in BCFF concentrations due to the implementation of Indian emission norms as mitigation measures, i.e., BS-IV (equivalent to Euro 4) and BS-VI (equivalent to Euro 6). It was found that the BCFF concentrations for BS-IV and BS-VI reduced by 35% and 75%, respectively. The model was also used to study the contribution of the different vehicular categories to BC concentration. [ABSTRACT FROM AUTHOR]

The targeted adjustment of carbon black (CB) particle size in electrode slurries is a key step in battery production. Based on the energy input and dispersion device, the resulting particle structure of CB differs significantly. Most frequently, especially in more recent publications, the median particle size was used to describe changes during dispersion. However, this value does not contain enough information to describe the dispersion progress of bimodally distributed particles sufficiently. In this short communication, a novel approach describing the dispersion progress of CB containing slurries is introduced. This method was developed utilizing the hierarchical structure and fragmentation behavior of CB. The Carbon Black Dispersion Index DICB allows quick and easy assessment of the dispersion progress by isolating the CB aggregates of the bimodal distribution. This value offers major benefits with regards to quality control and production monitoring. [ABSTRACT FROM AUTHOR]

Copyright of China Rubber Industry is the property of Editorial Office of China Rubber Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We investigated the influence of two fillers—CB (carbon black) and silica—on the H2 permeation of EPDM polymers crosslinked with sulfur in the pressure ranges 1.2–90 MPa. H2 uptake in the CB-blended EPDM revealed dual sorption (Henry's law and Langmuir model) when exposed to pressure. This phenomenon indicates that H2 uptake is determined by the polymer chain and filler-surface absorption characteristics. Moreover, single sorption characteristics for neat and silica-blended EPDM specimens obey Henry's law, indicating that H2 uptake is dominated by polymer chain absorption. The pressure-dependent diffusivity for the CB-filled EPDM is explained by Knudsen and bulk diffusion, divided at the critical pressure region. The neat and silica-blended EPDM specimens revealed that bulk diffusion behaviors decrease with decreasing pressure. The H2 diffusivities in CB-filled EPDM composites decrease because the impermeable filler increases the tortuosity in the polymer and causes filler–polymer interactions; the linear decrease in diffusivity in silica-blended EPDM was attributed to an increase in the tortuosity. Good correlations of permeability with density and tensile strength were observed. From the investigated relationships, it is possible to select EPDM candidates with the lowest H2-permeation properties as seal materials to prevent gas leakage under high pressure in H2-refueling stations. [ABSTRACT FROM AUTHOR]

The effect of carbon black structure on dispersion and barrier properties in BIIR/ENR 50 blends is studied extensively in this paper. Carbon blacks with different dibutyl phthalate values are used for the study and it is found that the structure of carbon black strongly affects both the mode of dispersion as well as barrier properties of the end product. The morphology of various carbon blacks in their raw state and in the matrix was studied using scanning electron microscopy and transmission electron microscopy techniques. The influence of carbon black structure on the reinforcing was studied by analyzing the physical properties. The rubber–filler interaction was measured using bound rubber content and filler–filler interaction was studied using rubber processing analyzer. For the same loading of carbon black, the high structure carbon black is more difficult to disperse in BIIR/ENR 50 blends compared to the low structure carbon black, leading to changes in permeability properties. [ABSTRACT FROM AUTHOR]

Carbon black has been replaced with silica as a reinforcing filler in tire tread compounds. This change has led to lower rolling resistance and improved hysteretic losses of so-called "green tires." However, the dispersion of silica in the rubber matrix is an important issue due to the poor compatibility of hydrophilic silica with a hydrophobic rubber matrix. Recently, some rubbers with polar functional groups that can interact with silica have been studied to improve the interaction in silica-filled rubber composites. In this work, we fabricated the silica-filled rubber composites with solution styrene butadiene rubber (SSBR) and epoxidized natural rubber (ENR) and evaluated their properties in a silica-containing rubber formulation compared to conventional SBR and NR. The silica-embedded polar rubber matrix exhibits remarkable enhancement in the modulus, tensile strength, and abrasion properties due to an efficient dispersion of the silica and improvement of interfacial interactions with the rubber matrix. The polar rubber composite exhibits an enhanced dry and wet braking and improved rolling resistance due to the improved dispersion of the silica in the rubber matrix. These results show that rubber composites prepared with polar rubbers have great potential for tire engineering applications. [ABSTRACT FROM AUTHOR]

We reported the use of an inverse vulcanised polysulfide (SP) as an intelligent interfacial modifier in the NR/CB composites to remarkably decrease the hysteresis loss by enhancing the interfacial adhesion and improving CB dispersion. Specifically, SP synthesized by the bulk copolymerization of sulfur and styrene was grafted onto CB surface by trapping the sulfur radicals generated from SP, and the grafted polysulfides can participate in the crosslinking reaction with NR, which greatly improves CB dispersion and strengthens interfacial adhesion in the composites. As a consequence, the rolling resistance and heat build-up of the modified composites are remarkably decreased, showing great advantages in tire application in term of reducing fuel consumption and extending service life. [Display omitted] • Inverse vulcanised polysulfide (SP) is synthesized and covalently grafted onto CB surface. • A model study demonstrates that the chemical reaction between SP grafted on CB and nature rubber (NR). • The grafted polysulfides onto CB react with NR, leading to improved interfacial adhesion and CB dispersion in the composites. • The rolling resistance and heat build-up of the modified composites is remarkably decreased. [ABSTRACT FROM AUTHOR]

At present, more and more flexible pressure sensors are used in wearable devices. The improvement of the adsorbability of nanomaterials on sponge flexible pressure sensors is an urgent problem to be solved. Here, using conductive carbon black with good dispersibility and small particle size as the conductive filler filled in the middle of the sponge can improve the absorbability of the sponge. A simple method of soaking a sponge with different thicknesses in conductive carbon black dispersion is used to obtain flexible pressure sensors based on conductive carbon black/sponge. We compare and analyze the differences in initial resistance and sensitivity of sponge pressure sensors with different thicknesses and select the sensor with higher sensitivity (0.194 kPa−1) for response time, recovery time, and stability tests. The sensor is used in the neck, wrist, knee, and other body parts for motion recognition. The two conductive carbon black/sponge sensors are placed orthogonally on the back to identify nod, tilt head, and placed on the elbow to test the angle of arm bending. Conductive carbon black/sponge flexible pressure sensor shows good application prospects in the wearable field. [ABSTRACT FROM AUTHOR]

The present study demonstrates the use of "pre‐mastication" technique for getting higher dispersion of organoclay, Cloisite 15A, in an inner liner compound based on 70:30 bromobutyl and natural rubber blend, in presence of higher concentration of carbon black (60 phr) for the improvement of functional properties like fatigue cut growth and air permeability resistance. Studies have showed that the organoclay was almost equally distributed within the blend both in absence as well as in presence of carbon black. The vulcanization curve showed a marked increase in cure acceleration as well as a significant rise in the maximum torque value because of higher crosslinking aided by the participation of the quaternary amine present in Cloisite 15A; however, in the carbon black loaded compound, the cure acceleration was not so pronounced because of engaging interaction between amine and functional groups of carbon black. The microscopic study revealed a good dispersion of Cloisite 15A within the elastomer blend‐ in presence of carbon black. The anisotropic platelets of Cloisite 15A and carbon black particles jointly formed "nano units", which occluded a portion of elastomer segments vis‐a‐vis partial intercalation within the clay gallery. Such a reinforcing model was instrumental in improving the physicomechanical and functional properties under static and dynamic conditions. The organoclay displayed a much‐improved properties at 2 and 4 phr doses in presence of 60 phr carbon black because of formation of enough "nano units" while deterioration was observed at 6 phr dose due to clay aggregation. Based on the results obtained on functional properties it was concluded that the 4 phr of organoclay compounded in "pre‐mastication" mode delivered the best improvement and thus it was recommended for future up‐scaling study. [ABSTRACT FROM AUTHOR]

Purpose. Development of the basics of technology for obtaining electrically conductive coatings using ultrasonic dispersion of carbon materials. Methods. The following methods were used in the work: ultrasonic dispersion of materials, optical microscopy, four-electrode method of measuring the electrical conductivity of coatings. The shielding effectiveness of materials was performed following ASTM D4935. The research results were processed using computer programs Microsoft office Excel and ImageJ. Results. The ultrasound treatment of carbon materials with a high specific surface area was performed. The influence of ultrasonic treatment on the efficiency of dispersion of carbon black in ethanol was established. The parameters of the process of destruction of natural graphite particles under the action of ultrasonic treatment are determined. The mechanism of structure formation into the composite material after ultrasonic treatment was proposed. The process of forming a spatial electrically conductive grid in a suspension by dispersed carbon black was established. It was shown that the use of ultrasonic treatment in the production of electromagnetic shielding materials allows to obtain oriented particles of the carbon component in the polymer matrix of the carrier and to get samples with high surface conductivity and shielding efficiency. Scientific novelty. The influence of ultrasonic treatment of carbon materials on the fabrication process, structure, and properties of shielding materials was established. Practical significance. The basics of the technology of the manufacturing process of shielding materials based on carbon materials pre-dispersed using ultrasonic treatment were developed. The optimal parameters of ultrasonic treatment of carbon materials for manufacturing shielding materials were substantiated. [ABSTRACT FROM AUTHOR]

Various processing parameters affect the dispersion of carbon black (CB) in a rubber matrix, of which mixing time plays a major role. The physical properties of a green compound namely bound rubber and Mooney viscosity along with mechanical and fatigue crack growth (FCG) are affected by the dispersion of filler particles. To determine the effect of mastication on dispersion, the mixing time was varied from 120 s to 600 s where it was gauged that an optimum range of mixing times display better dispersion. The difference in dispersion between the green and the cured compounds was also stark due to the flocculation mechanism. Longer mixing times do not show much decrease in agglomerate size on curing, that is, approximately 2%, whereas shorter time has led to a decrease of 20%. The FCG properties were studied using a tear and fatigue analyser, where the FCG rate displays a similar trend with the dispersion of CB. [ABSTRACT FROM AUTHOR]

In order to explore the space charge behavior of liquid silicone rubber (LSR) the pulsed electroacoustic (PEA) method has been applied. Due to the elastic nature of LSR, the PEA setup was optimized to ensure a constant contact pressure and thus a constant thickness of the LSR samples. For each sample, the temperature of the ground and the high-voltage electrode was permanently measured. The space charge behavior was investigated for neat LSR and for LSR samples with two different amounts of nanoscaled carbon black (CB). The results show in general a formation of homocharges at both electrodes. At 20 °C, the negative charge from the cathode moves towards the anode in the case of neat LSR. With increasing amount of CB, the negative charge is trapped near the cathode and the charge migration is suppressed. At higher temperature, an increasing amount of positive homocharges at the anode is observed, which is suppressed for LSR with CB nanofillers. The mean charge density between the electrodes is evaluated during polarization and depolarization measurement. The results show that the mean charge density increases with temperature and electric field strength, which is explained by the Schottky and Poole-Frenkel effect. In addition, it is observed that the mean attenuation rate during the depolarization time increases with increasing amount of CB nanofillers. [ABSTRACT FROM AUTHOR]

Carbon material (carbon black (CB) and carbon nanotube (CNT)-reinforced composites are being studied widely. The content of the reinforcing materials is known as the main influencing factor. However, the dispersion of the reinforcing materials is often neglected or, where it is investigated, not thoroughly evaluated. In this article, the dispersion states of carbon materials in the composite materials were quantitatively analyzed using an image processing method. Meanwhile, the reliability of the image analysis was verified through the testing results of the mechanical and rheological properties of the composites. Both CB and CNTs improved the mechanical properties of maleic anhydride-grafted polypropylene (PP)/ethylene propylene diene monomer composites, wherein their dispersion was the dominant factor instead of their content. The dispersion of the easily agglomerated CNT was significantly poorer than that of CB. Therefore, CB was better in inducing the crystallization of PP. [ABSTRACT FROM AUTHOR]

Gas emission is a major security risk in coal mining. Seal coating is an effective method for preventing gas from escaping, but the stability of inorganic particles in the coating has great influence on the sealing performance. This research was designed to study the effect of SHMP on the stability of a gas-sealing coating filler based on UFA. The effect of SHMP on powder dispersion behaviors was systematically investigated using a zeta potential tester, particle size analyzer, FT-IR, and SEM- EDS. To explore the dispersion mechanism of SHMP on typical powder materials (such as fly ash, carbon black, and graphite), the interaction energy among particles was calculated according to the classical and extended DLVO theory. The results indicate that the surface hydrophobic effects of graphite and carbon black were the main contributing factors to agglomeration. Further, the dispersant SHMP increases the interparticle electrostatic repulsions and steric hindrance, preventing particle agglomeration and ensuring the stability of fly ash-based filler in gas-sealing coatings. The results of pilot spraying test in a coal mine show that the added dispersant improved the gas-sealing efficiency of the coating and helped in its application in a coal mine. Image 1 • SHMP increases the inter particle electrostatic repulsions and steric hindrance. • Fly ash can be used as a kind of good filler in coating products. • The repulsive energy among particles agreed with extended DLVO theory. • The pilot test verified the gas sealing efficiency of the coating with SHMP. [ABSTRACT FROM AUTHOR]

The dithiothreitol (DTT) assay is the most commonly used method to quantify the oxidative potential of fine particles. However, the reported DTT decay rates of carbon black (CB) materials vary greatly among different researchers. This might have resulted from either the intrinsic toxicity of CB or the unsuitability of the DTT assay protocol for CB particles. In the current study, the protocol of the DTT assay for CB materials has been carefully evaluated. It was found that the dispersion degree of CB particles in water has a great influence on the DTT decay rate of CB materials. For CB particles (special black 4A (SB4A) and Printex U) and single-walled carbon nanotube tube (SWCNT), the DTT decay rate after sonication for 10 min became 4.2, 4.6 and 1.7 times higher than that without sonication. The rate continued to grow as a function of ultrasound time up to 30 min of sonication. Although the concentration of soluble transition metals and surface oxygen-containing species such as carbonyls increased slightly with sonication, they had no significant effects on the measured DTT activity, while the increase in the dispersion degree of aggregates was found to play a vital role in the observed enhancement of the DTT decay rates for different CB materials. Based on our results, 30 min of sonication is recommended for sample dispersion when measuring the DTT decay rate of CB materials. Unlabelled Image [ABSTRACT FROM AUTHOR]

In this study, carbon-black (CB) conductive electrodes were successfully printed using the high-resolution electrohydrodynamic (EHD) jet printing technique. The wrapping of CB bundles with a polymeric surfactant, Triton X-100 (TX-100), enabled the CB/TX-100 composites to well disperse in ethanol/deionized water for use in the preparation of conductive inks for EHD jet printing. By adjusting the voltage and operation distance, the applied electrostatic and gravity forces to the loaded CB/TX-100 inks overcame the fluid forces (viscosity and surface tension) to elongate the droplet and provide continuous jet lines, where the ink widths were smaller than the diameter of the nozzle. The EHD-printed CB/TX-100 in the stable cone-jet mode formed conductive lines and various pattern shapes. These conductive lines were utilized as source and drain electrodes of organic field-effect transistors (OFETs) with solution-processed organic semiconductors. The OFET with printed CB/TX-100 electrodes exhibited better electrical performances, including a higher saturation mobility and smaller hysteresis, than those of the reference OFET with Au electrodes. Image 1 • Carbon black/Triton X-100 surfactant composite solutions are prepared for EHD printing. • CB patterns are successfully printed under stable cone-jet and exhibit good conductivity. • OFETs with EHD-printed CB exhibited better performances with negligible hysteresis. [ABSTRACT FROM AUTHOR]

This study focuses on modifying the surface of carbon black (CB) with hydrogen peroxide to raise light absorbance of dispersed CB in water without capping agent. Four kinds of commercial CB, trademarked as M900, M1000, M1100, and Mogul L, respectively, were used as study materials. The ultrasonic bath was utilized to disperse the treated CB in de‐ionic (DI) water in the absence of capping agent. The surface properties of treated CB were characterized by thermal gravimetric analysis, X‐ray photoelectron spectroscope, and Fourier transform infrared spectroscopy, as well as the light absorbance, stability, and morphology of treated CB particles dispersed in DI water were analyzed by ultraviolet‐visible light absorption spectroscopy, dynamic light scattering, and transmission electron microscopy. As shown in the results, in particular, it was found that the oxygen on the surface of CB could be increased by the treatment of peroxide hydrogen, resulting in stable dispersion without capping agent to sharply increase light absorption value of Mogul L CB in DI water from 38 to 545 g−1 dm2. [ABSTRACT FROM AUTHOR]

Manganese‐zinc ferrite as magnetic filler is compounded with NBR or NR based elastomer matrices in two steps. Manganese‐zinc ferrite is the most important part of elastomer compounds because of its magnetic properties, but it is inactive filler and thus carbon black is added into the rubber formulations as well. The rubber compound filled only with ferrite exhibits high viscosity and it is not able to be processed by extrusion. For this reason, rheological properties of all compounds with different ratio of processing additives and fillers are studied. It has been found out in our previous research that rubber compounds filled with 200 phr of ferrite showed the best electromagnetic shielding performance. Dispersion Z and dispersion D of cured and uncured elastomer compounds with processing additives Werbablend and Werbalub, which are mixed in laboratory and industrial kneading machine, are determined on an instrument disperGRADERTM αview. [ABSTRACT FROM AUTHOR]

Coupling agents are intended to promote filler dispersion by providing a bridge between the filler and the rubber phase. This study investigated the ability of a novel physical coupling agent, poly(butadiene- graft -pentafluorostyrene) in a mixture with polypentafluorostyrene, to improve rubber-filler interactions and suppress filler-filler networking in carbon-black-reinforced styrene-butadiene rubber (SBR), and thereby decrease hysteresis. The electron-rich aromatic rings of carbon black are involved in arene-perfluoroarene interactions with the electron-poor pentafluorostyrene aromatic rings of the coupling agent. The SBR chains in the rubber compound have an affinity for the polybutadiene backbone of the coupling agent. The interactions between carbon black and the coupling agent were analyzed using Raman spectroscopy, transmission electron microscopy, zeta potential measurements, surface area measurements, and scanning electron microscopy. Filler flocculation analysis showed that the coupling agent improves the dispersion and lowers the energy of dissipation. The hysteresis loss, quantified in terms of loss tangent values at 60 °C, was reduced by up to 12% due to the coupling agent's promotion of better filler-rubber interactions. The influence of the PPFS graft length was also studied. [ABSTRACT FROM AUTHOR]

In this paper the influence of multi-walled carbon nanotubes (MWCNTs) (the average outside diameter of 8 nm) in carbon black mixture (industrial carbon black N330) on the technological, physicomechanical, gasbarrier properties and visco-elastic behaviour of the rubber while incorporating simultaneously two fillers are considered. For the comparative evaluation of the obtained results two check samples: the single-filler carbon black only and MWCNTs were used. As a result combined application of two fillers has improved the technological, mechanical, gasbarrier properties and visco-elastic behaviour of the obtained elastomeric materials compared to the samples using a single-filler material. [ABSTRACT FROM AUTHOR]

The aim of this work was to obtain a suitable dispersion of carbon black (CB) nanoparticles in a polymer matrix using sodium dodecyl sulfate (SDS). The effect of SDS surfactant on dispersion of CB nanoparticles in solvent and epoxy resin and also the corrosion behavior of CB coatings were investigated by means of scanning and transmission electron microscopies, Zeta potential, dynamic light scattering and thermogravimetric analyser. The effect of CB nanoparticles dispersion on corrosion properties of nanocomposites was investigated by electrochemical impedance spectroscopy. The results showed improved corrosion resistance of the modified CB/epoxy coatings. [ABSTRACT FROM AUTHOR]

The conductive network within a lithium-ion battery electrode is mainly influenced by the process parameters chosen for the dry mixing and wet dispersing step during the production of a coatable electrode slurry, consisting of well-defined components. This conductive network, which results from the electrode's microstructure, plays a major role for the resulting battery cell performance, especially for high performance and power applications. Notable differences can be observed in the subsequently manufactured electrodes due to process-related modifications in the carbon black agglomerate size; mechanical, electrical, and, thus, electrochemical properties are significantly changing with the process parameters set. To allow for a direct correlation of these properties with the electrode structure, a characteristic parameter to describe the carbon black structure in electrode coatings is developed. Based on mercury intrusion measurements, the internal porosity of carbon black particles was determined as a characteristic parameter for the conductive microstructure. For a wide variety of lithium-ion battery cathode samples, the carbon black porosity can be well related to important electrode properties. This underscores the relevance of this carbon black-based microstructure parameter for a knowledge-based process and product optimization. [Display omitted] • Carbon black porosity as a structural parameter for LIB is developed and proven. • Wet dispersion and dry mixing can be used to adjust the carbon black porosity. • Carbon black porosity determines C-rate performance in the form of an optimum curve. [ABSTRACT FROM AUTHOR]

Highlights: [•] Pt content of Pt-PEI-CB is higher than that of Pt-CB. [•] Cell performance is related to Pt particle size, dispersion and metallic Pt content. [•] PEI functionalized to CB plays an important role for durability of electrocatalyst. [ABSTRACT FROM AUTHOR]

Abstract: The stabilization mechanism of aqueous carbon black suspensions by Cetyltrimethylammoniumbromide (CTAB) is studied in this paper. The adsorption of the surfactant CTAB on the carbon black particles was investigated on dried samples by thermogravimetric analyses (TGA), nitrogen adsorption and attenuated total reflection Fourier transformation infrared spectroscopy (ATR-FTIR) as well as in suspension by zeta potential measurements and atomic force microscopy. The particles are stabilized by an adsorbed CTAB monolayer as can be concluded from the results of TGA and of AFM investigations using a liquid cell. Extended DLVO calculations including the steric contribution of CTAB reveal that carbon particles with an adsorbed monolayer of CTAB exhibit sufficient colloidal stability. This result is in qualitative agreement with the experimental results. [Copyright &y& Elsevier]

In this paper, a new strategy to encapsulate and disperse carbon black by an in situ controlling free radical polymerization of 1,1-Diphenylenthyene (DPE) method was developed. Firstly, a living amphipathic precursor polymer of P (AA-BA) containing DPE unit was synthesized. This precursor could be grafted or absorbed on the surface of small carbon black particles to prevent further aggregation of carbon black. And the DPE unit in the living amphipathic precursor could initiate following monomer to form polymer shell via in situ polymerization. Carbon black/polymer core-shell composite particles with 69.6 wt.% polymer shell were prepared. The encapsulated carbon black had a small particle size and high performance on dispersibility and stability. Encapsulation mechanism of this method was confirmed by analyses of TEM, UV-vis, H NMR, C NMR, TGA, and other instruments. [ABSTRACT FROM AUTHOR]

Abstract: A processing route to disperse carbon black (CB) nanoparticles in aqueous and various organic solvents was developed by a high-shear-agitated bead milling process in water with various cationic dispersant and further surface modification using anionic surfactant. First, for dispersing CB nanoparticles in an aqueous suspension, polyethyleneimine (PEI) and a new cationic dispersant, which was synthesized by the reaction of PEI with a hydrophobic toluoyl group (T-PEI), were used to stabilize CB nanoparticles in water during the bead milling process, and their results were compared. When PEI was used as a dispersant, the conditions for obtaining CB nanoparticles in water in a dispersed state were few and most additive conditions resulted in a segregated and inhomogeneous CB suspension. However, when T-PEI was used as a dispersant, a highly dispersed CB suspension was obtained under a wide range of T-PEI additive conditions, even when the additive amount was as low as 1.0mg/m2. Next, for dispersing CB nanoparticles in various organic solvents, an anionic surfactant that branched into hydrophilic polyethylene glycol (PEG) and hydrophobic alkyl segments was adsorbed on CB nanoparticles stabilized with PEI or T-PEI. It was found that CB dispersible in various solvents could be obtained successfully only when the anionic surfactant was adsorbed on PEI-stabilized CB nanoparticles. The proposed action mechanism of each surfactant on the CB surface and its effect on the stability of CB in an aqueous/organic solvent are discussed. [Copyright &y& Elsevier]

Composites of polypropylene and carbon black were melt compounded by a vibration-assisted process. For comparison, conventional extrusion was also used for preparation of the same composites. A throughput of the vibration-assisted process was established to be higher than that of conventional extrusion. Microscopic images of the extrudates demonstrated better dispersion of the fillers when the vibration force field was applied. The mechanical properties and viscoelastic behavior of the composites were studied and the results were discussed in the context of the reinforcing action of the fillers and the higher level of polypropylene chain scission accompanying the vibration-assisted process. [ABSTRACT FROM PUBLISHER]

The pH-responsive polyelectrolyte, named poly(methyl vinyl ether-alt-maleic anhydride) (PVM/MA), was grafted onto the surface of carbon black (CB) by ultrasonically degraded method. The effect of pH on the dispersion of PVM/MA grafted CB in water and waterborne polyurethane (WPU) was studied. Particle size of PVM/MA grafted CB and its transmission electron microscope images showed the increasing of pH in the suspension of grafted CB easily causes the aggregates of grafted CB. Furthermore, scanning electron microscope images showed grafted CB had better dispersibility than that of untreated CB in WPU emulsion or corresponding solid composite. When grafted CB was neutralized in aqueous solution, the compatibility between PVM/MA grafted CB and WPU got poor. In addition, the dispersion of grafted CB in solid composite could be controlled through tuning the composite resistance. [ABSTRACT FROM PUBLISHER]

Abstract: The dispersion and stability of carbon black (CB) nanoparticles in water were investigated using ultra-violet–visible (UV–vis) spectroscopy. After studying the effects of five dispersants, the most appropriate ones, Triton X-100 and N220 CB, were selected. UV–vis spectra of samples containing different amounts of Triton X-100 and a constant amount of CB were used to find the optimal circumstances of CB dispersion. Also, the stability of the dispersion was studied and it was found that the optimum conditions could be achieved in colloidal mixture containing CB and Triton X-100 in a weight ratio of 2:1. It was clarified that the mixtures containing Triton X-100 up to 50wt% CB were stable over a period of 20 days. In order to support the UV–vis results additional techniques such as AFM, PSA and FE-SEM were employed. [Copyright &y& Elsevier]

Abstract: Dispersion of carbon black powders in aqueous medium was investigated by using anionic surfactant sodium oleate and a series of nonionic surfactants which were selected systematically to represent varying degrees of ethoxylation. Single and binary mixtures of the nonionic and ionic surfactants were employed in zeta potential and particle size measurements and a high affinity of surfactants on carbon black powders was beheld as they significantly changed the zeta potential and size distribution of the powders. But, noticeable differences between the surfactants were also observed, for example, as the nonionic surfactants reduced the absolute magnitude of zeta potential of powders in a wide pH range of 3.0–11.0, Na oleate made the zeta potential of the powders more negative under similar experimental conditions. The carbon black suspensions were agitated in a vessel having a standard geometry and the particle size measurements were carried out at desired time intervals without disturbance of the suspensions and interruption of agitation. Effect of surfactants on stability and dispersion of the powders were recognized with the reduction in mean particle sizes, as, in the absence of surfactant, the mean particle size could not be reduced below 24.0μm even after 210min of stirring, it could be reduced to 5.35μm after 120min of stirring in the presence of only 30g/L of nonionic surfactant. Generally, it was found that nonionic surfactants could wet and stabilize carbon black powders in aqueous medium better than anionic surfactant. The reason was explained by molecular structure and bulk properties of surfactants. [Copyright &y& Elsevier]

Considering the balance between rapidly growing global tire demand and scarcity of natural resources, recycling and reclaiming techniques of tire rubber have become the state of the art. Herein, we set out to implement a self-designed thermo-oxidative reactor for the exfoliation of carbon black (CB) from ground tire rubber, which is efficiently functioned under a thermo-oxidative reclaiming condition without any additive. The exfoliation of CB from rubber vulcanizate was realized by scission of main chain, and of cross-linked network. The degree of scission was discussed through gel permeation chromatography and using Horikx theory. Sol fraction tremendously increased to 66.0% after thermo-oxidative reclamation at 200 °C for 20 min. Thermo-oxidative scission underwent through the oxidative cleavage of main chain, and of sulfur cross-links, proved by Fourier transform infrared spectroscopy. The ultrafine exfoliation of CB from rubber proved by field emission scanning electron microscopy. The exfoliation was further improved by two roll milling. Exfoliated rubber was incorporated within tire rubber composites as a reinforcing material due to the core-shell structured CB, which was observed with increased effects to the rubber composites. This work presents a potential contribution to the industrial recycling for future applications and to control the pollution of waste tires. [Display omitted] [ABSTRACT FROM AUTHOR]

• Dispersion analysis of different carbon based nanofillers in water. • Morphology of carbon nanofillers determines dispersibility. • Detailed porosity analysis of nanocomposites. • Porosity influenced by surfactant and nanofillers. The dispersion behaviour of different carbon-based nanofillers in deionized (DI) water was investigated in the study at hand by using polycarboxylates as surfactants. Carbon nanotubes (CNTs), carbon black (CB) and expanded graphite (EG) were firstly characterized in respect of their morphology. Subsequently, they were dispersed in DI water using two polycarboxylate (PCE) comb-type copolymers which differed in length of their chemical backbones. Optical microscopy and light transmission analysis during centrifugation disclosed a clear difference in the dispersibility among the nanofillers under investigation. Small CB particles showed excellent dispersion in DI water even with no surfactant. CNT was dispersed significantly better than EG, whereby the PCE with the longer backbone yielded better filler dispersion in both cases. After incorporating the carbon nanofillers into a cementitious matrix, interestingly, the highest compressive and flexural strengths at an early age were measured for the CNT samples with worse filler dispersion. This effect is explained by the role of the PCE and the aspect ratio of the carbon nanofiller, both of which determine the microstructure in the hardened cement-based matrix collaboratively. [ABSTRACT FROM AUTHOR]

Precipitated silica in combination with bifunctional organosilanes almost fully replaces currently the commonly used carbon black fillers in modern passenger car tire tread compounds to improve tire properties such as wet traction (safety) and rolling resistance (fuel consumption). However, it is still challenging to reach a sufficient level of abrasion resistance (service life). An optimum macrodispersion quality of the silica is a fundamental precondition for an optimum abrasion resistance. This goal can be reached by the development of new tailor-made highly dispersible silica grades. In order to achieve this, it is essential to be aware of the analytical silica parameters, which affect the dispersion process. One of these parameters known from carbon black is the structure of the filler. To gain deeper insights into the in-rubber dispersibility of the silica, the structure was investigated by two different methods, the DOA measurement and the void volume measurement. The results were correlated to the in-rubber macrodispersion. In contrast to carbon black filled compounds, no sufficient correlation of the structure with the macrodispersion could be found for the silica-filled compounds. Therefore, it was concluded that the morphology of silica differs from that one that is claimed for carbon black. Additional investigations like TEM, FT-IR and X-ray diffraction measurements were carried out. Carbon black shows a more elastic structure, which can withstand the external forces during the mixing process in a better way. Silica contains a much higher void volume in the structure even after exposed to high forces. These new findings will help to understand the macrodispersion process in rubber in a better way. [ABSTRACT FROM AUTHOR]

Underground coal seam fire is one of the serious problems caused by coal mining activities. Hence, the present study is focused on investigating the potential emission of black carbon (BC) and its dispersion from the fire-affected area located in the Jharia coal field, Dhanbad district of the Jharkhand state of India. The real-time BC concentration measurements in the active fire area and the adjacent neighbouring urban area were studied and reported. Results showed an average concentration of BC was 12.54 μ g m - 3 in the fumes/smokes emitting from the surface cracks and vents at the fire-affected zone. The continuous probability distribution functions, i.e., lognormal, gamma and Weibull, were used to fit the BC data individually, and among these lognormal fits, the best were for the medium-range values. Furthermore, the robustness of the obtained BC concentration was also explained by these models. All fitness was in good agreement, in the studied area, with the coefficient of regression ranging between 0.84 and 0.96. Both the experimental and predicted results clearly indicated the contribution of the BC that discharged from the coal seam fire as a source of particulate pollutant. Spatial modelling was also performed to validate the experimental consistency of BC concentration while the model was in good agreement with the underground coal fire zone as compared to the rest. [ABSTRACT FROM AUTHOR]