Conductive carbon black

Power Gables. The materials mostly used to produce power cables are ethylene copolymers loaded with conductive carbon black for ... 

Antistats such as polyoxyethylenes (151,152) and A/-alkyl polycarbonamide (153) are added to nylon to reduce static charge and improve moisture transport and soil release in fabrics. These additives also alter the luster of fiber spun from bright polymer. Static reduction in carpets is achieved primarily by the use of fibers modified with conductive carbon black (see Antistatic agents Carbon, carbon black). 

Bicomponent technology has been used to introduce functional and novelty effects other than stretch to nylon fibers. For instance, antistatic yams are made by spinning a conductive carbon-black polymer dispersion as a core with a sheath of nylon (188) and as a side-by-side configuration (189). At 0.1—1.0% implants, these conductive filaments give durable static resistance to nylon carpets without interfering with dye coloration. Conductive materials such as carbon black or metals as a sheath around a core of nylon interfere with color, especially light shades. 

Vulcani2ed mbber is an insulator (volume resistivity is 10 Q-cm), and the static generated by mbber tires created serious problems in vehicles until the introduction of electrically conductive carbon black as a reinforcing pigment. An excellent correlation was found between the potential generated and the resistivity of the tires (127,128) (see Rubber natural). 

N. Prost, Conductive Bacbber Compounds—Compounding with Extra-Conductive Carbon Black, Phillips Petroleum Chemicals Bulletin, June 1985. 

Carbon-Zinc Sealant, cathode conductive carbon black matrix... 

Sterling NS is a fairly conductive carbon black and dispersions of... 

Power Cables. The materials mosdy used to produce power cables are ethylene copolymers loaded with conductive carbon black for semiconductive shielding layers, polyethylene or ethylene—propylene mbber-based compounds as insulations, and either thermoplastic materials (eg, polyethylene, PVC) or thermosetting (based on chlorinated polyethylene (CPE), chlorosulfonated polyethylene (CSPE), chloroprene, etc) for jackets. 

Carbon is used in lithium-ion cells for different functions conductive carbon black and/or graphite additives are applied in both the negative and the positive electrode to improve the electronic conductivity of the electrodes. These conductive additives constitute a fraction of up to about 10% of the total carbon consumption. The major fraction is represented by the active carbon materials which are electrochemically reduced and oxidized in the negative electrode during the battery charge and discharge process, respectively. 

Among the 9 million tons of carbon black which are produced globally per year, only a small fraction of very specific, high-purity conductive carbon blacks can be used as conductive additive in lithium-ion batteries. A traditional conductive carbon is acetylene black, a special form of a thermal black produced by the thermal decomposition of hydrocarbon feedstock.74-75 The particularity of acetylene black to other thermal carbon black production is that the starting hydrocarbon, acetylene, exothermally decomposes above 800°C.75-77 Once the reaction is started, the acetylene decomposition autogenously provides the energy required for the cracking of acetylene to carbon followed by the synthesis of the carbon black ... 

Typical OAN Numbers from DBPA, BET Specific Surface Area, Relative Conductivity, Dispersibility, and Purity of Various Conductive Carbon Blacks from Different Manufacturing Processes... 

When applied as conductive additive in the positive electrode, graphite and carbon black show complementary properties which are summarized in Table 7.3. The decision which carbon type should be selected depends on the cell requirements and the type of active electrode materials used in the electrodes. The TEM pictures in Figure 7.7 compare the morphology of a typical conductive carbon black and a graphite powder and illustrate the dimensional differences of the primary particles of a factor of about 10. 

Fig. 30a behaves similarly to that of the NBR/N220-samples shown in Fig. 29, i.e., above a critical frequency it increases according to a power law with an exponent n significantly smaller than one. In particular, just below the percolation threshold for 0=0.15 the slope of the regression line in Fig. 30a equals 0.98, while above the percolation threshold for 0=0.2 it yields n= 0.65. This transition of the scaling behavior of the a.c.-conductivity at the percolation threshold results from the formation of a conducting carbon black network with a self-similar structure on mesoscopic length scales. 

Conductivity in plastic coatings is achieved through the use of a conductive pigment, most often conductive carbon black. Conductivities of the order of 1 Mfl/cm2 are required for effective transfer efficiencies of subsequent topcoat applications. Without the use of a conductive primer, plastics in themselves would not be conductive, and hence would be very unreceptive to topcoat transfer efficiencies of greater than 20 percent. 

Carbon black is far less resistant to the flow of electricity on its surface than the plastic resins in which the black is dispersed. Therefore, carbon black can be used to lower the resistivity of plastics, imparting antistatic, semiconductive, or conductive properties. End uses for conductive carbon blacks range from material handling bins and device carrier tapes in the electronics industry to fuel system components to semiconductive strand shielding for power cable. 

In a typical experimental measurement a Nd YAG laser fires a 5 ns pulse on to the target electrode. It is convenient to use a polymeric material for the electrode, made conductive by the addition of conductive carbon black, to achieve intimate contact with the specimen. Adding a thin layer of a volatile liquid to the electrode surface just prior to firing the laser greatly enhances the magnitude of the signal, by helping to increase the size of the pressure pulse... 

One way which is often used to impart an artificial structure to the dispersion of a carbon black in a composite is to coat the particles of a moulding powder, e.g. 1 mm diameter particles of polyethylene, with a conductive carbon black by mixing them together in a ball-mill. If subsequent moulding does not shear the mixture too much (rotational casting is ideal) the black remains concentrated in a honeycomb-like network, and the overall conductivity is greatly enhanced over that of a uniform dispersion of the same proportion of black. 

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