Magnetic orientation studies of synthetic mesophase pitches

✍ Scribed by C.A. Kovac; I.C. Lewis

• Publisher: Elsevier Science
• Year: 1978
• Tongue: English
• Weight: 650 KB
• Volume: 16
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(78)90089-1

✦ Synopsis

Previous studies have shown that mesophase spheres with Brooks-and-Taylor structure are nematic liquid crystals which orient with their molecular c-axes perpendicular to a magnetic field. Mesophase spheres in synthetic pitches made from anthracene and naphthalene with AI& show similar magnetic orientation behavior; however, they have a novel structure, which was elucidated with the use of sensitive tint microscopy and magnetic orientation experiments. In the proposed structure, the aromatic molecules within the bulk of the sphere, are stacked in parallel layers, similar to those in the Brooks-and-Taylor spheres. However, at the interface of the sphere with surroundina isotroDic ohase. the molecular olanes are oriented parallel to the surface, unlike those observed in the Brooks-and-Taylor bphkres.