Static scattering behavior polyelectrolytes

These results confirm the observation that polyelectrolyte aqueous solutions show two separate decay modes in the autocorrelation function and support our contention that ionic polymer systems generally behave similarly in polar solvents [23], To support this, it may be added that similar dynamic scattering behavior was recently reported for another type of ionomer, polyurethane ionomer, dissolved in a polar solvent, dimethylacetamide (e = 38) [92], Finally, it should be stressed that the explanation given above for light scattering (both static and dynamic) behavior of salt-free polyelectrolytes is based on the major role of intermolecular electrostatic interactions in causing characteristic behavior. No intramolecular interactions are explicitly included to explain the behavior. This is in accord with our contention that much of the polyelectrolyte behavior, especially structure-related aspects, is determined by intermolecular interactions [23]. 

Polyelectrolyte behavior is exhibited by solutions of SPS in DMF, Fig. 12. At low polymer concentrations, the viscosity Increases as a result of repulsion between the unshielded anions, which Increases the hydrodynamic volume of the polymer. The structure of SPS in DMF solutions as determined by static and dynamic light scattering is also discussed in the chapter by Hara and Wu. 

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