{"term":{"id":"03850","title":"mesophase pitch","longtitle":"IUPAC Gold Book - mesophase pitch","doi":"10.1351\/goldbook.M03850","code":"M03850","status":"current","definitions":[{"id":1,"text":"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.","notes":{"1":"The carbonaceous mesophase particles are formed from the aromatics of high molecular mass in mesogenic pitch, which have not yet been aggregated to particles detectable by optical microscopy within the apparently isotropic pitch matrix. The carbonaceous mesophase is insoluble in quinoline and pyridine, but the amount of mesophase measured from microscopical observation appears somewhat higher because parts of the carbonaceous mesophase can be extracted by the solvents."},"links":[{"term":"bulk mesophase","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/B00754"},{"term":"carbonaceous mesophase","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/C00822"},{"term":"hydrocarbons","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/H02889"},{"term":"isotropic","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/I03353"},{"term":"mesogenic pitch","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/M03841"},{"term":"mesophase","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/M03849"},{"term":"pitch","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/P04677"}],"sources":["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)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/M03850\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/M03850\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/M03850\/plain"},"citation":"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. 10.1351\/goldbook.M03850","license":"The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/) for individual terms.","collection":"If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .","disclaimer":"The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.","accessed":"2026-04-19T01:17:54+00:00"}}