Material properties of viscoelastic liquids in uniaxial extension Available to Purchase

Based on a simple analysis using the Larson model, a superposition procedure is proposed for constant stretch rate data from fiber spinning experiments. This procedure appears to be able to account for the shear prehistory undergone by the fluid in the spinneret and yields true extensional stress growth data. The effectiveness of this method is demonstrated with the help of previously published isothermal fiber spinning data on one polymer melt and new data on one polymer solution. For constant stretch rate spinning at constant force, it is further shown that all the data can be represented by a single equation with known coefficients. Comparison with literature data on the transient extensional viscosity suggests that this same equation may also hold for the high stretch‐rate filament stretching of molten polymers at constant stretch rate. This result should lead to a considerable reduction in the amount of experimental work needed to characterize polymeric fluids.