Amount Of Carbon Black Research Articles

Structurally Coloured Secondary Particles Composed of Black and White Colloidal Particles

This study investigated the colourful secondary particles formed by controlling the aggregation states of colloidal silica particles and the enhancement of the structural colouration of the secondary particles caused by adding black particles. We obtained glossy, partially structurally coloured secondary particles in the absence of NaCl, but matte, whitish secondary particles were obtained in the presence of NaCl. When a small amount of carbon black was incorporated into both types of secondary particles, the incoherent multiple scattering of light from the amorphous region was considerably reduced. However, the peak intensities in the reflection spectra, caused by Bragg reflection and by coherent single wavelength scattering, were only slightly decreased. Consequently, a brighter structural colour of these secondary particles was observed with the naked eye. Furthermore, when magnetite was added as a black particle, the coloured secondary particles could be moved and collected by applying an external magnetic field.

Processability and Mechanical Properties of CB/PVC Composite

In our study, a new kind of material was prepared by melt blending with PVC as the matrix and carbon black (CB) as the filler. With the amount of CB increasing, the notched impact strength of composite increased greatly, however the tensile strength declined. When the amount of CB was 30%, the notched impact strength of composite was 9.66 KJ/m2, the tensile strength dropped from 48.3MPa to 33.2MPa. The distribution of CB in the PVC matrix is relatively uniform and no large agglomeration in the PVC matrix.

Hydrophobic and ice-retarding properties of doped silicone rubber coatings

In this study, room-temperature vulcanized silicone rubber coatings were prepared by spin-coating hexane-diluted suspensions onto aluminum substrates. Various amounts of carbon-black, titania or ceria nanopowders were incorporated to the coatings as dopants in order to modify their surface roughness, hydrophobic and electrical properties. By changing deposition parameters, superhydrophobic surfaces could be prepared. The freezing behavior of small water droplets was investigated on nanostructured composite surfaces exhibiting different values of wetting hysteresis and was compared with that on uncoated polished aluminum. At approximately −15°C, the water droplets were found to freeze on polished aluminum after approximately 5s, while their freezing was delayed to as long as ∼12–13min on superhydrophobic nanocomposite surfaces doped with ceria or titania powders. Correlations between the wetting hysteresis (and surface roughness) of the samples and freezing time of water droplets on their surfaces were also observed. Icing tests demonstrated delayed ice formation and lower adhesion strength on superhydrophobic samples with small wetting hysteresis.

STRAIN-INDUCED CRYSTALLIZATION AND MECHANICAL PROPERTIES OF NBR COMPOSITES WITH CARBON NANOTUBE AND CARBON BLACK

Abstract The mechanical properties and strain-induced crystallization (SIC) of elastomeric composites were investigated as functions of the extension ratio (λ), multiwalled carbon nanotube (CNT) content, and carbon black (CB) content. The tensile strength and modulus gradually increase with increasing CNT content when compared with the matrix and the filled rubbers with same amount of CB. Both properties of rubber with CB and CNT show the magnitude of each CNT and CB component following the Pythagorean Theorem. The ratio of tensile modulus is much higher than that of tensile strength because of the CNT shape/orientation and an imperfect adhesion between CNT and rubber. The tensile strength and modulus of the composite with a CNT content of 9 phr increases up to 31% and 91%, respectively, compared with the matrix. Differential scanning calorimetry (DSC) analysis reveals that the degree of SIC increases with an increase in CNT content. Mechanical properties have a linear relation with the latent heat of crystallization (LHc), depending on the CNT content. As the extension ratio increases, the glass-transition temperature (Tg) of the composite increases for CB- and CNT-reinforced cases. However, the LHc has a maximum of λ = 1.5 for the CNT-reinforced case, which relates to a CNT shape and an imperfect adhesion with rubber. Based on these results, the reinforcing mechanisms of CNT and CB are discussed.

Adsorption Kinetics and Isotherms of Cu (II) and Cd (II) onto Oxidized Nano Carbon Black

A new kind of sorbent, Oxidized Nano Carbon Black (OCB), was prepared with the acid potassium permanganate. The adsorption kinetics,isotherms of Cu (II) and Cd (II) onto Nano Carbon Black(CB) and Oxidized Nano Carbon Black(OCB) were investigated. The experimental data were analyzed by Langmuir, Freundlich isotherm, Pseudo first order equation and Pseudo second order equation. The results demonstrated that the Langmuir isotherm provided a better fit to the experimental data of CB and the OBC fitted well into Freundlich adsorption isotherm. The adsorption capacity of Cu2+ and Cd2+onto oxidized Carbon black was significantly enhanced after modification. The maximum amount of CB was 16.129mg/g for Cu2+, 5.747mg/g for Cd2+, the maximum amount of OCB was 83.333mg/g for Cu2+, 10.3097mg/g for Cd2+, respectively. The Freundlich parameters of OCB were KF, Cu = 0.360, nCu = 1.16, KF, Cd = 1.777 and nCd = 3.086. The values of n > 1 indicated a favorable adsorption process. The study of adsorption kinetic showed that the adsorption stage of Cu and Cd onto sorbents could be divided into two stages: fast reaction and slow reaction. The adsorption kinetic model of metal on OCB followed pseudo second order model well (RCu2=0.985, RCd2=0.987) and the data of CB fitted pseudo first order model well (RCu2=0.983, RCd2=0.998).

Influence of Carbon Black on Crosslink Density of Natural Rubber

Vulcanization and reinforcement are two important factors contributing to the properties of vulcanized rubber. In order to investigate the influence of carbon black (CB) on chemical crosslinking, three groups of samples with different crosslink densities were prepared. In each group with the same crosslink density, different amounts of CB were introduced. Data fitting showed that delta torque (ΔM = M H–M L, the difference between the highest and lowest torques during curing) in the cure curves of each group had a good linear relationship with CB load and extrapolation of the fitting lines almost intercepted the x coordinate at the same value, which indicated that CB had no influence on the chemical crosslinking of the rubber. To verify the above result, a series of nonfilled natural rubber (NR) vulcanizates with different crosslink densities were studied using equilibrium swelling and the swelling ratios were compared with those of corresponding CB filled rubbers with the same sulfur and accelerator amount. The results of both the equilibrium swelling and NMR relaxation parameter measurements showed that CB filled vulcanizates had higher apparent crosslink densities than those of unfilled ones due to the strong interaction between rubber molecules and the surface of the CB particles. The swelling ratios of filled rubbers had a parallel relationship with those of the unfilled ones which indicated that CB had little influence on chemical crosslink density introduced by chemical vulcanization.

Carbon Black‐Modified Screen‐Printed Electrodes as Electroanalytical Tools

AbstractIn this paper screen‐printed electrodes (SPEs) bulk modified with carbon black (CB) or with CB dispersion in DMF:water were developed and characterized. We have demonstrated by cyclic voltammetry, SEM and electrochemical impedance spectroscopy that an increase of CB amount on the working electrode surface increases the electrochemical performances of CB‐SPE. The CB‐SPE was tested with ferricyanide, epinephrine, benzoquinone and H2O2 demonstrating in any case an enhancement of electrochemical activity. For H2O2 amperometric detection, a sensitivity of 241.4±5.7 mA M−1 cm−2 and 1.46±0.06 mA M−1 cm−2 was obtained, respectively, for CB‐SPE and bare SPE.

Rechargeable Direct Carbon Fuel Cells using Directly Supplied Carbon Black Fuel

Rechargeable Direct Carbon Fuel Cells (RDCFCs) using directly supplied carbon black (CB) fuels were successfully demonstrated. Three different supplying methods of CB fuel were investigated focusing on direct contact or non-contact between the CB fuel and the anode. A small amount of CB in contact with the anode effectively enhanced the performance, particularly during initial power generation. When the maximum power density was 33 mW/cm2 and 17.5 mW/cm2, the fuel utilization was 66% and 74%, respectively. High power density with high fuel utilization was achieved by RDCFCs at the current density where the CO supply rate equaled the electrochemical reaction rate. Increasing the amount of CB led to an improved maximum power density. As fuel, amorphous carbon with a large specific surface area was more suitable than graphite.

Influence of carbon black on slurry compositions for tape cast porous piezoelectric ceramics

Functionally graded porous piezoceramics are of interest for ultrasonic applications as the gradual decrease of acoustical impedance improves the transfer of acoustic energy to water or biological tissues, assuring at the same time an high piezoelectric response. This ceramic architecture can be easily produced by tape casting as long as each step of the production process (slurry formulation, lamination and thermal treatments) is fully optimized. A thorough discussion on the process of slurry optimization is here reported. The Carbon Black (CB) was chosen as pore former agent and slurry formulations with CB concentration ranging between 3 and 43 vol% referred to the ceramic powder were optimized. Linear relationships between CB and solvent, binder and plasticizers amounts were found. The additional polymer (AP) required to optimize the slurry formulations was found to proportionally increase with CB amount. The abovementioned linear relationships were shown to allow an easy planning of the slurry composition to obtain defects-free green tapes for any CB concentration in the range considered.

Influences of Black Carbon Addition on Mechanical Performance of Low-Carbon MgO-C Composite

Abstract Carbon black-phenolic resin composite binders with various amounts of nanoscale carbon black were prepared through adding KH-550 coupling agent and high-speed mixer. The effects of nanoscale carbon black amount added on viscosity of the composite binders were studied. Low-carbon MgO-C specimens were fabricated with these composite binders. Effects of nanoscale carbon black contents (0, 2. 5%, 5%, 10%, and 15% of phenolic resin in mass percent) on mechanical properties of low-carbon MgO-C specimens were investigated. The results revealed that the viscosity of the composite binder increased rapidly with increase of nanoscale carbon black content, and that CMOR, HMOR (high modulus of rupture) and CCS (cold crushing strength) of the specimens increased gradually with increase of nanoscale carbon black content as well.

Sorption study of toluene and xylene in aqueous solutions by recycled tires crumb rubber

Sorption of toluene and xylene by tire crumb rubber (TCR) and its main components: carbon black (CB) and styrene-butadiene polymer (SBP) were evaluated. The 12 starting concentrations of adsorbates in aqueous solutions ranged from 0.05 mg/L to 100.0 mg/L. The amounts of CB and SBP used in the sorption tests were determined considering their typical contents in tire crumb rubber (30% and 60% w/w, respectively). Freundlich's isotherms and Scatchard plot parameters suggested a two-step sorption process when TCR was used as the sorbent; whereas a single-step route was apparent when the sorption experiments were carried out with CB or SBP. Freundlich's n parameter was estimated at 0.65 for CB and 1.0 for both TCR and SBP. A removal of 60% of toluene and 81% of xylene from starting 50 ppm solutions was attained in the first 30 minutes of contact using 5 g/L of TCR.

대기압 화염 플라즈마 처리한 다중벽 탄소나노튜브 및 카본블랙 강화 고무복합재료의 기계적 특성 연구

다중벽 탄소나노튜브(MWCNT) 및 카본블랙(CB) 함유량, 대기압 화염 플라즈마(APFP) 처리 그리고 산처리를 함수로 한 고무복합재료의 기계적 특성에 대해 연구하였다. 고무복합재료의 인장강도 및 탄성률은 MWCNT의 함유량 증가에 따라 순수상태 그리고 동일량의 CB가 보강된 상태에 비해 증가하였다. APFP 처리한 MWCNT를 보강한 복합재료는 처리하지 않은 경우에 비해 강화효과(높은 강도, 높 은 탄성률 그리고 높은 연성)를 보였다. 반면에 APFP 처리한 CB를 함유한 복합재료는 처리하지 않은 경우에 비해 연화효과(높은 강도, 낮은 탄성률 그리고 높은 연성)를 보였다. 산처리 시간이 1시간에서 2시간으로 증가할수록, 그리고 황산의 농도가 60%에서 90%로 증가할수록 복합재료의 인장강도와 탄성률은 감소하였다. 전체적으로 MWCNT 함유량, CB 함유량, 대기압 화염 플라즈마 처리, 황산 농도 그리고 산처리 시간 등이 고무복합재료의 기계적 특성에 영향을 미치는 중요한 변수임을 확인하였다.

In situ self-organization of carbon black–polyaniline composites from nanospheres to nanorods: Synthesis, morphology, structure and electrical conductivity

Nanostructured composites of polyaniline (PANI) with carbon black (CB) were synthesized by an in situ self-organization process. The synthesis is based on the polymerization of aniline in a micellar solution of p-toluenesulfonic acid (TSA) with different weight percentages of CB using ammonium peroxydisulfate (APS) as the oxidizing agent. Field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), UV–vis spectroscopy, and the four-probe meter were used to study the morphological, structural, thermal, and electrical properties of CB–PANI nanocomposites. The results demonstrate that the morphology, thermal stability, and electrical conductivity of the nanocomposites were significantly influenced by the content of CB. SEM results reveal that there was a transition in morphology from composite nanospheres to one-dimensional (1D) composite long nanorods with an increase of CB content. XRD and UV–vis spectra results revealed that there was an increase in the crystallinity and a shift of quinoid transition bands towards lower wavelengths as the amount of CB in the composite increased. The mechanism for the formation of nanostructured composites was explained on the basis of the self-organization of micelles. CB–PANI nanocomposites with a maximum electrical conductivity of 1.38 S/cm were obtained; this is at least three orders of magnitude higher than that of pristine PANI.

Dispersion and stability of carbon black nanoparticles, studied by ultraviolet–visible spectroscopy

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 50 wt% 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.

The Effect of Nanosized Carbon Black on the Physical and Thermomechanical Properties of Al2O3–SiC–SiO2–C Composite

The effects of using nanosized carbon black in the range of 0–10 weight percentages on the physical and thermomechanical properties of Al2O3–SiC–SiO2–graphite refractory composites were investigated. Nanosized carbon black addition improved the relative heat resistance and oxidation resistance of composites. The bulk density of the composites is reduced with increasing carbon black (CB) content. Increase in CB content first causes an increase in the apparent porosity, but at more than 3 wt% amount of CB, a decrease of apparent porosity was observed. The cold crushing strength (CCS) increased with increasing CB content in samples fired at 800∘C and in samples fired at 1500∘C when the content is increased to 3 wt%, but the CCS decreased with increasing CB content in samples fired at 1500∘C when the CB content was less than 3 wt%. The composite without CB exhibits the highest value of CCS at firing temperature of 1500∘C.

Catalytic oxidation for carbon-black simulating diesel particulate matter over promoted Pt/Al 2O 3 catalysts

Catalytic oxidation activity of carbon-black (CB) simulating the soot of diesel particulate matters to CO 2 over 3Pt/Al 2O 3, 3Pt5Mn/Al 2O 3 and 3Pt/30Ba–Al 2O 3 catalysts is investigated with model gases of diesel emission. In case of the large amount of CB compared to the amount of catalyst (3/1, w/w) in the mixture sample, insufficient oxygen at the point of sudden increase in the amount of CO 2 is leaded to the partial oxidation using the lattice oxygen of the catalyst. And the peaks of CO 2 after the first peak were attributed to the regional combustion of the CB, which was not in contact with catalyst particles. The fresh 3Pt5Mn was estimated to the oxidation states on the catalyst surface by XPS. For used sample at 700 °C, the BEs of Pt 4d5 was revealed to metallic state Pt(0) (314.4 eV) in a predominant levels compared with Pt(II) (317.3 eV). While BEs of Mn 2p were similar to that obtained from the fresh 3Pt5Mn. It is suggested that Pt is in charge of the roles in CB-oxidation, using the lattice oxygen of the catalyst. Two-stage catalytic system with the strategies of promoting the soot oxidation and NO x reduction, simultaneously, were composed of the CB oxidation catalyst and the diesel oxidation catalyst. The catalytic oxidation of CB was accelerated by activated oxidants and exothermic reaction resulted from the diesel oxidation catalyst, which lies in upstream of two-stage. But the system with the CB oxidation catalyst sited in the upstream showed the initiation of CB oxidation at a lower temperature than the other case. Two-stage catalytic system composed of 3Pt5Mn with CB in the upstream and DOC in the downstream showed high oxidation activity with 95% consumption rate of CB to the total loaded CB in the range of 100–500 °C during the TPR process.

Electrical conductivity and rheological behavior of multiphase polymer composites containing conducting carbon black

AbstractMultiphase polymer composites of carbon black (CB), polypropylene (PP) and low density polyethylene (LDPE) were prepared by melt‐mixing method to reduce the amount of CB in the conductive composites. SEM images showed that CB preferably located in LDPE phase and formed electrically conductive path. The measurement of conductive properties showed that the ternary materials possessed lower percolation than binary composites of CB/PP or CB/LDPE, the former was ∼6 wt% and the latter was 9–10 wt%. Positive temperature coefficient (PTC) effects of the binary and ternary composites were investigated, indicating that the latter exhibited a relatively high PTC intensity. A rheological percolation estimated by a power law function is 2.66 wt% of CB loading, suggesting an onset of solid‐like behavior at low frequencies. This difference between the electrical and rheological percolation thresholds may be understood in terms of the smaller CB–CB distance required for electrical conductivity as compared with that required to impede polymer mobility. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers

Investigate of Electrical Conductivity of Shape-Memory Polymer Filled with Carbon Black

A new system of thermoset styrene-based shape-memory polymer (SMP) filled with carbon black (CB) is investigated. To realize the electroactive stimuli of SMP, the electrical conductivity of SMP filled with various amounts of CB is characterized. The percolation threshold of electrically conductive SMP filled with CB is about 3% (volume fraction of CB), which is much lower than many other electrically conductive polymers. When applying a voltage of 30V, the shape recovery process of SMP/CB(10 vol%) can be realized in about 100s. In addition, the thermomechanical properties are also characterized by differential scanning calorimetery (DSC).

Electrical and Mechanical Properties of Carbon Black -Filled Poly (Styrene-Co-Butyl Acrylate) Latex Reinforced Polyester Nonwoven Composites

The main goal of the present research work was to fabricate lightweight nonwoven fabric impregnated composites for antistatic applications. Composites were fabricated by impregnating polyester nonwoven fabric with aqueous carbon black (CB) filled poly (styrene-co-butyl acrylate) latex. The effect of the amount of CB on the mechanical and electrical properties has been studied. Tensile strength, stitch tear strength and surface hardness were reduced by an increase in the wt.% of CB. The percentage elongation of the composites increased drastically because of the presence of diethylene glycol plasticiser in the CB dispersion. The dielectric constant, dissipation factor and loss factor of the composites increased with increasing wt.% of CB and decreased with increasing frequency. The reduction in dielectric properties with increasing frequency could be due to the delocalisation of charge carriers.

Characterization of Carbon Filler Distribution Ratio in Polyisoprene/Polybutadiene Rubber Blends by High-Resolution Solid-State 13C NMR

The distribution ratio of carbon black (CB) in a blend of polyisoprene rubber (IR) and polybutadiene rubber (BR) is characterized using high-resolution solid-state 13C NMR. The relationships between the line width of the polymer's resonance lines and CB contents are estimated for both the IR/CB and BR/CB composites from the dipolar decoupling/magic angle spinning (DD/MAS) 13C NMR spectra. For the IR/CB composite, the IR line width increases with the increasing CB content. A similar relationship is obtained between the BR line width and CB contents for the BR/CB composite. These relationships are used as calibration curves. On the basis of these calibration curves, the distribution ratio of CB in the IR/BR rubber blend is determined. It is found for the IR/BR/CB composite that the amount of CB in the BR phase is approximately twice as high as that of CB in the IR phase, irrespective of the CB content. The sum of the amounts of CB in both the IR and BR phases, determined from the above 13C NMR experiments, mostly agree with the amount of CB originally added to the compound. This verifies the validity of the CB distribution determination method by 13C NMR, as proposed in this study. A comparison with a CB-gel method, which can only be used for unvulcanized rubber blends, further confirms the results obtained from the 13C NMR.