Dynamic birefringence and conformation of poly-p-phenylene terephthalamide molecules in solution

✍ Scribed by V.N. Tsvetkov; I.N. Shtennikova; T.V. Peker; G.I. Kudriavtsev; A.V. Volokhina; V.D. Kalmykova

• Publisher: Elsevier Science
• Year: 1977
• Tongue: English
• Weight: 288 KB
• Volume: 13
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(77)90125-2

✦ Synopsis

Flow birefringence (FB) for samples of poly-p-phenylene terephthalamide (PPPhTPhA) dissolved in sulphuric acid has been investigated; intrinsic viscosities [~/] of the solutions have been measured. Characteristic values of FB [n] and orientation angles [X/9] of the solutions were determined. Coefficients of rotatory diffusion Dr and molecular weights M of all the samples of PPPhTPhA were calculated using the values of [2/9] and [t/]. Dependences of [r/] and Dr on M show that the conformation of the PPPhTPhA molecules in solution resembles a slightly bending rod. Quantitative data on the equilibrium rigidity of the PPPhTPhA molecules were obtained from comparison of characteristic values of [n] and [X/9] at different M and from the dependence of [n]/[r/]