mesophase pitch
A pitch with a complex mixture of numerous essentially aromatic hydrocarbons containing anisotropic liquid-crystalline particles (carbonaceous mesophase) detectable by optical microscopy and capable of coalescence into the bulk mesophase.
The @C00822@ particles are formed from the aromatics of high molecular mass in @M03841@, which have not yet been aggregated to particles detectable by optical microscopy within the apparently @I03353@ @P04677@ matrix. The @C00822@ is insoluble in quinoline and pyridine, but the amount of @M03849@ measured from microscopical observation appears somewhat higher because parts of the @C00822@ can be extracted by the solvents.
PAC, 1995, 67, 473. 'Recommended terminology for the description of carbon as a solid (IUPAC Recommendations 1995)' on page 496 (