Abstract
An elongational rheometer is used to measure the relaxation times λ and the steady terminal elongational viscosities ηE,t of aqueous solutions of ionic and nonionic polymers at various concentrations in Θ and in good solvents. In the corresponding ηE,t/λ nomogram the results yield two typical limiting curves—one for solutions of nonionic polymers and another for solutions of ionic polymers. The curves characterize the elongational behavior of the polymer solutions. The elongational flow results in data that are intermediate to the two limiting curves for polymers in aqueous salt solutions and for aqueous solutions of mixtures of ionic and nonionic polymers. By means of an empirical correlation, the relaxation time and the steady terminal elongational viscosity are normalized such that the nomogram can be applied to polymers in various solvents. Thus a simple and reliable method for determining the behavior of polymer solutions in elongational flows is achieved.
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