Petroleum pitch

Examples of polymers which form anisotropic polymer melts iaclude petroleum pitches, polyesters, polyethers, polyphosphaziaes, a-poly- -xyljlene, and polysdoxanes. Synthesis goals iaclude the iacorporation of a Hquid crystal-like entity iato the maia chaia of the polymer to iacrease the strength and thermal stabiHty of the materials that are formed from the Hquid crystal precursor, the locking ia of Hquid crystalline properties of the fluid iato the soHd phase, and the production of extended chain polymers that are soluble ia organic solvents rather than sulfuric acid. 

The principal binder material, coal-tar pitch, is produced by the distillation of coal tar. Coal tar is obtained primarily as a by-product of the destmctive distillation of bituminous coal in coke ovens during the production of metallurgical coke. Petroleum pitch is used to a much lesser extent as a binder in carbon and graphite manufacture. Because of its low sohds content, petroleum pitch is used as an impregnant to strengthen carbon artifacts prior to graphitization. 

Certain compounds found in some coal-tar and petroleum pitches are carcinogenic. Individuals working with pitches or exposed to fumes or dust should wear protective clothing to avoid skin contact. Respirators should be worn when pitch dust or fume concentrations in the air are above estabHshed limits. 

Romine, H. E., Petroleum pitch. Presentation at Clemson University, Clemson, SC, 3 December, 1987. 

Fig. 3. Second cycle voltage profiles of carbons representative of regions (I), (2), and (3). a) JMI synthetic graphite, b) Crowley petroleum pitch heated to 550°C, and c) a resole resin heated to 1000°C.

Petroleum pitch was obtained from Kureha Company, Japan (designated here as KS pitch). A second petroleum pitch was obtained from the Crowley Tar Company, U.S.A. (designated here as CRO pitch). Polyvinyl chloride (PVC) was obtained from the Aldrich Chemical Company (U.S.A.). These samples are all soft carbon precursors. 

Petroleum-handel, m. petroleum trade, -hei zung, /. heating with petroleum, -pech, n. petroleum pitch, -prober, -priifer, m. petroleum tester, -quelle, /. oil well, -seifen-briihe,/. Agric.) kerosene emulsion. 

Petrol-koks, m. petroleum coke, oil coke, -pech, n. petroleum pitch, -saure, /. petrolic acid. 

The commercial fibers are produced from rayon, polyacrylonitrile, and petroleum pitch. When acrylonitrile is heated in air at moderate temperatures (= 220°C ), HCN is lost, and a ladder polymer is thought to be the intermediate ... 

Coke materials are generally made by heat-treatment of petroleum pitch or coal-tar pitch in an N2 atmosphere. Coke made from petroleum is called "petroleum coke" and that from coal is called "pitch coke". These materials have the closest-packed hexagonal structures. The crystallinity of coke materials is not so high as that of graphite. The crystallite size of coke along the c-axis (Lc) is small (about 10-20 A) and the interlayer distance (d value about 3.38-3.80 A) is large. 

Yasuda and Kakiyama34 used this method to determine sulphone residues in petroleum pitches and related materials. 

Petroleum petroleum pitch delayed coke, calcined coke needle coke, carbon fibers, binder and matrix carbon1... 

Grint, A. Swietlik, U. Marsh, H. Carbonization and Liquid-crystal (Mesophase) Development-9. The Co-carbonization of Vitralns with Ashland A200 Petroleum Pitch. Fuel, 1979, M,... 

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