Sizes Monitoring of Polyelectrolyte Flexible Chains over the Entire Range of Ionic Strength through Viscometry of Dilute Solutions

100 years after the birth of polymer science, it can be stated that viscometry of dilute polymer solutions is the most popular method among molecular hydrodynamics methods, the purpose of which is to obtain the molecular characteristics of individual polymer chains. The viscous flow of dilute aqueous solutions of polyelectrolytes–statistical copolymers of N-methyl-N-vinylacetamide and N-methyl-N-vinylamine hydrochloride was investigated in the range of ionic strengths from the minimum (10–6 M) to the maximum possible 6 M NaCl. Intrinsic viscosities were determined as ∂lnηr/∂c at c → 0. The obtained generalized dependence of the intrinsic viscosity on the ionic strength of the solution in a double logarithmic scale is sigmoidal. The intrinsic viscosity values change insignificantly in the range 10–6–10–4 M. The nature of the change in the hydrodynamic volume of charged macromolecules in the entire range of ionic strengths of solutions is discussed in comparison with the theory of single polyelectrolyte macromolecule in the salt solution developed by Vasilevskaya et al., [26].