Term: mesophase pitch
https://doi.org/10.1351/goldbook.M03850

Definition:
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.

Note: 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.

Related Terms:
1) carbonaceous mesophase (http://doi.org/10.1351/goldbook.C00822).
2) isotropic (http://doi.org/10.1351/goldbook.I03353).
3) pitch (http://doi.org/10.1351/goldbook.P04677).
4) mesophase (http://doi.org/10.1351/goldbook.M03849).
5) hydrocarbons (http://doi.org/10.1351/goldbook.H02889).
6) mesogenic pitch (http://doi.org/10.1351/goldbook.M03841).
7) bulk mesophase (http://doi.org/10.1351/goldbook.B00754).

Source: PAC, 1995, 67, 473. 'Recommended terminology for the description of carbon as a solid (IUPAC Recommendations 1995)' on page 496 (https://doi.org/10.1351/pac199567030473)

Citation: 'mesophase pitch' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.M03850

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