Optical anisotropy and conformation of polyamidebenzimidazole in an organic solvent and in concentrated sulphuric acid

✍ Scribed by I.N. Shtennikova; T.V. Peker; T.I. Garmonova; N.A. Mikhailova

• Publisher: Elsevier Science
• Year: 1984
• Tongue: English
• Weight: 441 KB
• Volume: 20
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(84)90085-5

✦ Synopsis

Flow birefringence, intrinsic orientation and intrinsic viscosities of polyamidebenzimidazole (PABI) and poly-meta-phenylene-isophthalamide (PPIP) molecules have been studied for a wide range of molecular weights. The optical and conformational properties of PABI molecules in dimethyl acetamide (DMAA) and concentrated sulphuric acid are compared. The conformation of PABI (kinetically rigid coil) is shown to be practically the same in both solvents. This fact indicates the practical absence of a significant role of protonization of molecules during formation of conformation of aromatic polyamides macromolecules in sulphuric acid. There is comparison of the coefficients G = [g/g]RT/M[q]qo for PABI and PPIP molecules in sulphuric acid and DMAA. Values of G of 0.65 + 0.05 for PABI and 0.30 _+ 0.03 for PPIP correspond to those for rigid and flexible Gaussian coils respectively.