Accession Number : ADA113805

Title :   Pitch Fractionation.

Descriptive Note : Technical rept.,

Corporate Author : AEROSPACE CORP EL SEGUNDO CA MATERIALS SCIENCES LAB

Personal Author(s) : Weinberg,V L ; White,J L

PDF Url : ADA113805

Report Date : 15 Dec 1981

Pagination or Media Count : 49

Abstract : Petroleum pitch (Ashland A240) has been subjected to thermal treatment and solvent fractionation to produce refined pitches to be evaluated as impregnants for carbon-carbon composites. The solvent fractions were obtained by sequential Soxhlet extraction with solvents such as hexane, cyclohexane, toluene, and pyridine. The most severe thermal treatment produced a mesophase pitch (approximately 50% mesophase); an appreciable portion of the mesophase was soluble in strong solvents. There were substantial differences in chemical composition and in pyrolysis behavior of the fractions. As the depth of fraction increased, the pyrolysis yield and bloating increased, and the microstructure of the coke became finer until glassy microconstituents were formed in the deepest fractions.

Descriptors :   *Fractionation, *Pitch(Material), Petroleum products, Heat treatment, Thermal properties, Carbon carbon composites, Coal, Refining, Solvent extraction, Impregnation, Pyrolysis, Polymerization, Mesopause, Cyclohexanes, Hexanes, Pyrimidines, toluenes, Microstructure

Subject Categories : Physical Chemistry
      Miscellaneous Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE