Hydrodynamic studies of dilute pitch solutions: The shape and size of pitch molecules

✍ Scribed by Mototsugu Sakai; Kiyomi Sasaki; Michio Inagaki

• Publisher: Elsevier Science
• Year: 1983
• Tongue: English
• Weight: 413 KB
• Volume: 21
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(83)90244-0

✦ Synopsis

The shape and size of pitch molecules were discussed through the measurements of the intrinsic viscosity [q] and the diffusion coefficient D of molecular weight fractionated petroleum pitches in dilute chloroform solutions, where [r~] was measured by an Ubbelohde viscometer, and D by NorthrupMcBain diaphragm cells. Hydrodynamical considerations on the [r~] vs D relationship lead to a conclusion that pitch molecules examined are of 3-dimensional structure, the axial ratio being l-3 under the oblate ellipsoid assumption, and their sizes being about IO _ 20 A in equatorial diameter.