The effect of CaCl_2 on the solution behavior of aromatic polysulfonamide in dimethylformamide

摘要

The solution behavior of aromatic polysulfonamide (PSA) in dimethylformamide (DMF) with the addition of CaCl_2 was studied by rheology and viscosity measurements. It is shown that no maximum in its intrinsic viscosity as a function of CaC_2 concentration was observed and the relationship between η_(sp) and PSA concentration c is consistent with the predicted scaling of θ solvent for both DMF and DMF/4% CaCl_2. However, the intrinsic viscosity, zero shear-rate viscosity and specific viscosity of PSA/DMF/4% CaCl_2 were found larger than that of PSA/DMF, which could be related to the extending of PSA chain in solution due to the increase of the interaction between the PSA macromolecules and solvent with addition of CaCl_2.