Translational friction and the characteristic visocity of polyamide benzimidazole molecules in solution

• Published in: Polymer science USSR 1985, Vol.27 (8), p.1823-1829
• Main Authors: Pavlov, G.M., Selyunin, S.G., Shil'dyayeva, N.A., Yakopson, S.M., Efros, L.S., Usova, S.V.
• Format: Article
• Language: English
• ISSN: 0032-3950; 1878-268X
• DOI: 10.1016/0032-3950(85)90200-X

The authors have investigated the intrinsic viscosity [η], the coefficient of translational diffusion D and the sedimentation coefficient S of 32 samples and fractions of poly-(2,2′- p-phenylene-(5-benzimidazole)) isophthalamides in DMAA + 3% LiCl in the interval of molecular ular masses 5≤ M × 10 −3 ≤ 190. In the region M > 10 4 they obtained the ratios [ ν] =· × × g 10 t-5 M 0·81, D 0 = 4·3 × 10 −9 M −0·57 and S 0 = 7·1 × 10 −16 M 0. β43 . The vlaue of the hydrodynamic invariant A 0 = (3β2 ± 0β12 × 10 −17 Jβdeg −1β mole − 1 3 , temperature coefficient of viscosity negative d In [ ν]/ dT= −2·3 × 10 −3. The equilibrium rigidity of the chains modelling the molecules of poly(2,2′- p-phenylene-(5-benzimidazole)) isophthalamide is estimated and the length of the Kuhn segment A lies within the limits 64≤ A × 10 10 M≤95 to which corresponds the rotation braking factor 1·1 ⩽ σ⩽1·3.