Acetylene carbon black

Acetylene carbon black is derived from the pyrolysis (thermal decomposition) of acetylene gas. The production volumes of acetylene black are extremely low compared to the billions of pounds of furnace blacks produced annually. Acetylene blacks are basically used where special compounding applications are needed, such as improved thermal conductivity. One of the larger areas of use is in the production of tire-curing bladders (because of the need for better thermal conductivity). 

No standard method has been developed. However, some of the tests used in ASTM D1765 are used to characterize acetylene black. 

Acetylene blacks are occasionally used when greater thermal conductivity is needed for a rubber application. This greater thermal conductivity is probably due to a higher graphite content. Thermal blacks may also impart greater electrical conductivity to a rubber compound as well. 

There are other compounding techniques available to improve the thermal and electrical conductivity of a given rubber formulation. 

Tight Supply Situations in the Past and Future Supply Outlook 

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Fig. 8. Flow curves of dispersion of 5 % acetylene carbon black (highly active) in poly(isobutylene) for different temperatures (indicated near curves)...

Fig. 12. Flow curves of poly(isobutylene), containing different concentrations of active filler (acetylene carbon black). Concentration (in volume percent) is indicated near the curves. A is the region of flow for stresses exceeding the yield stress B is the region directly adjacent to the yield stress...

Fig. 14. Amplitude dependences (y0 is the amplitude of cyclic deformations) of the elastic modulus for frequency a) = 63 s 1 13% dispersion of acetylene carbon black in low- (/) and high-molecular (2) poly(isobutylene)s...

Acetylene/carbon black is also quite effective but has an initial irreversible capacity that cannot be ignored. The amount of irreversible loss for acetylene black component ranges up to 20%. The particle size of conductive additives is recommended to be less than 5 microns. The addition is very effective to improve to improve 1) cycle life, 2) high power capability, and 3) the initial charge efficiency (reduce the initial irreversible... 

The structure of the porous GDL is governed by the type of carbon and by the hydrophobic polymer which is used in its preparation. These, in turn, greatly influence the performance of the PEMFC. The most widely used carbons have been an oil furnace carbon (Vulcan XC-72R) and acetylene carbon black. 

Acetylene/carbon black provides a conductive diluent in the Mn02 cathode and... 

Cathode may also contain acetylene/carbon black to absorb electrolyte... 

Acetylene, carbon black formation role, 280 Activation energy carbonization, 228... 

High-rate electrode characteristics of V2O5 sol/carbon composites were studied. The V2O5 sol was prepared by a reaction between metallic vanadium and a hydrogen peroxide solution. The acetylene carbon black powder was added to the sol together with acetone in the form of a homogeneous suspension. A composite of amorphous V2O5 and carbon black was introduced into a macroporous nickel... 

High temperature Plasma (1380°F-1650°F) 900-1100 (1650°F-2010°F) >1650 Secondary reactions additional hydrogen Acetylene carbon black... 

The reduction of O " concentration under action of CCI4, CI2, C (C is acetylene carbon black)-i-Cl2 and COCI2 may be explained by the occurrence of the following reactions ... 

Alternatively, other additives (for example, graphite, other earbons, or titanium oxide powders) may be employed to reduee the porosity of either layer, thereby impeding the flow of water through the anode. It may be advantageous to employ a porosity-redueing additive mixture of polytetrafluoroethylene and aeetylene earbon blaek, in whieh the anode catalyst layer comprises between about 12% and 32% by weight of polytetrafluoroethylene and between about 0.03 and 0.2 mg cm of acetylene carbon black. 

Acrylonitrile butadiene rubber is a semi-conducting rubber which can be made fiiUy conductive by the addition of (fast extrusion furnace) blacks and acetylene carbon blacks. 

Carbon blacks are the most used among all pigments. They have a high pigmentation power and they improve many of the physical properties of polymers, such as light stability, processibility, and mechanical properties. Channel black has been banned in the United States since 1976 only all gas-fired channel black is still permissible in food contact applications. Other carbon blacks, mainly thermal and lamp carbon blacks, are used in rubber reinforcement acetylene carbon black is interesting for its electrical conductivity and is used as an antistatic agent. Activated carbon is also used in some cases. 

FIGURE 2.3 Resistivity of carbon blacks (carbon black N134 and acetylene carbon black) in lead sulfate and at 2% dry loading in dry, unformed active material. (From D. P. Boden et al., J. Power Sources, 195(14), 4470-4493, 2010.)... 

Creating EVM with optimum hot-air resistance requires either carbon black or light-colored, non-active fillers. The best resistance is obtained using acetylene carbon black. Powdery talc, chalk, or kaolin grades are appropriate for light-colored mixtures [697]. 

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