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Fig. 1. (a) Schematic layout of MPR and (b) cross section of slit flow cell. First citation in article

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Fig. 2. Linear rheology of (a) 250k (filled symbols) and 485k PS (open symbols) melts and (b) PB 48 (squares), 156 (triangles), and 210k (circles) melts with comparison to predictions from the tube theory, parameterized by a chemistry- and temperature-dependent entanglement modulus G_e and Rouse relaxation time of an entanglement segment _e, and the material dependent number of entanglements Z. First citation in article

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Fig. 3. Nonlinear shear and extensional (485k PS only) transients (rates from 0.01–3  s^–1) rheology of 250k (a) and 485k PS (b) melts at 170 °C (the extensional data were time-temperature shifted from 160 °C). Comparison curves are predictions from the full tube theory of Eq. 2, parameterized by plateau modulus G, entanglement time _e, and the number of entanglements Z. First citation in article

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Fig. 4. RoliePoly model predictions and comparison to shear transients for (a) PS 262, and (b) PS 485. Strain rates and temperatures are as for Fig. 3. First citation in article

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Fig. 5. PS 262 at a piston speed of 0.5 mm/s (wall shear rate of 29  s^–1). The flow is marginally within Regime (3). Observed stress field is on the left, predicted on the right. First citation in article

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Fig. 6. Experiment and calculation of stress fields for the PS485 monodisperse melt. Piston speeds are (a) 0.05 mm/s, (b) 0.2 mm/s, (c) 5 mm/s, giving wall shear rates of (a) 2.9  s^–1, (b) 12  s^–1, and (c) 290  s^–1. Flows (a) is in Regime (2), flow (b) on the threshold of regime (3) and (c) (calculated only) deeply into Regime (3). First citation in article

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Fig. 7. Experimental and simulated stress field from the PB210 melt in the 11:1 contraction at a wall shear rate of 29  s^–1 at a temperature of 80 °C. The mean dimensionless (by reptation) shear rate is 3.6. First citation in article

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Fig. 8. Simulated (solid curve) and experimental data (crosses) on the pressure drop transient for flow start up in an 11:1 contraction of the PS485 melt at 170 °C. The effect of melt compressibility in the upstream piston is marked. The dashed curve shows the modified simulations of the pressure drop when the upstream boundary velocity condition was modulated with a single exponential growth. First citation in article

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Fig. 9. PS262 K at 200 °C—Evolution of flow birefringence at piston speed of 0.5 mm/s (steady-state wall shear rate of 29  s^–1): (a) t = 0.25  s, (b) t = 0.5  s, (c) t = 0.75  s, (d) t = 1.0  s, (e) t = 1.25  s, and (f) t = 1.5  s (fully developed). First citation in article

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Fig. 10. Observed and simulated steady-state pressure drops as a function of piston speed for the PS485 melt. Above 0.5 mm/s (wall shear rate of 29  s^–1), the observed values fall markedly below the predicted values, but this is also the regime in which the experiment showed flow instabilities, which are suppressed in the simulations. First citation in article