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BY 4.0 license Open Access Published by De Gruyter November 16, 2018

Flow Behavior of a Polypropylene Melt in Capillary Dies

  • E. Mitsoulis , H.-J. Luger , J. Miethlinger and W. Friesenbichler

Abstract

Using capillary dies having different diameters, D, and length-to-diameter L/D ratios, a full rheological characterization has been carried out for a polypropylene melt, and the experimental data have been fitted both with a viscous model (Cross) and a viscoelastic one (the Kaye – Bernstein, Kearsley, Zapas/Papanastasiou, Scriven, Macosko or K-BKZ/PSM model). Particular emphasis has been given on the pressure-dependence of viscosity. It was found that only the viscoelastic simulations were capable of reproducing the experimental data well, while any viscous modeling always underestimates the pressures, especially at the higher apparent shear rates and L/D ratios.


*Correspondence address, Mail address: Evan Mitsoulis, School of Mining Engineering and Metallurgy, National Technical University of Athens, Zografou 157 80, Athens, Greece, E-mail:

References

Ansari, M., Alabbas, A., Mitsoulis, E. and Hatzikiriakos, S. G., “Entry Flows of Polyethylene Melts in Tapered Dies”, Int. Polym. Proc., 25, 287296 (2010) 10.3139/217.2360Search in Google Scholar

Ansari, M., Zisis, Th., Hatzikiriakos, S. G. and Mitsoulis, E., “Capillary Flow of Low-Density Polyethylene”, Polym. Eng. Sci., 52, 649662 (2012a) 10.1002/pen.22130Search in Google Scholar

Ansari, M., Hatzikiriakos, S. G. and Mitsoulis, E., “Slip Effects in HDPE Flows”, J. Non-Newtonian Fluid Mech., 167–168, 1829 (2012b)10.1016/j.jnnfm.2011.09.007Search in Google Scholar

Bagley, E. B., “End Corrections in the Capillary Flow of Polyethylene”, J. Appl. Phys., 28, 624627 (1957) 10.1063/1.1722814Search in Google Scholar

Baird, D. G., Collias, D. I., “Chapter 7. Extrusion Dies”, in Polymer Processing: Principles and Design, Butterworth-Heinemann, Newton, MA, USA, p. 177211 (1995)Search in Google Scholar

Barakos, G., Mitsoulis, E., “Numerical Simulation of Extrusion through Orifice Dies and Prediction of Bagley Correction for an IUPAC-LDPE Melt”, J. Rheol., 39, 193209 (1995) 10.1122/1.550700Search in Google Scholar

Barakos, G., Mitsoulis, E., “Non-Isothermal Viscoelastic Simulations of Extrusion through Dies and Prediction of the Bending Phenomenon”, J. Non-Newtonian Fluid Mech., 62, 5579 (1996) 10.1016/0377-0257(95)01385-7Search in Google Scholar

Binding, D. M., “An Approximate Analysis for Contraction and Converging Flows”, J. Non-Newtonian Fluid Mech., 27, 173189 (1988) 10.1016/0377-0257(88)85012-2Search in Google Scholar

Binding, D. M., “Further Considerations of Axisymmetric Contraction Flows”, J. Non-Newtonian Fluid Mech., 41, 2742 (1991) 10.1016/0377-0257(91)87034-USearch in Google Scholar

Binding, D. M., Couch, M. A. and Walters, K., “The Pressure Dependence of the Shear and Elongational Properties of Polymer Melts”, J. Non-Newtonian Fluid Mech., 79, 137155 (1998) 10.1016/S0377-0257(98)00102-5Search in Google Scholar

Carreras, E. S., El Kissi, N., Piau, J.-M., Toussaint, F. and Nigen, S., “Pressure Effects on Viscosity and Flow Stability of Polyethylene Melts during Extrusion”, Rheol. Acta, 45, 209222 (2006) 10.1007/s00397-005-0010-1Search in Google Scholar

Cogswell, F. N., “Measuring the Extensional Viscosity of Polymer Melts”, Trans. Soc. Rheol., 16, 383403 (1972) 10.1122/1.549257Search in Google Scholar

Cogswell, F. N.: Polymer Melt Rheology – A Guide To Industrial Practice, John Wiley, New York (1981) PMid:7267956;Search in Google Scholar

Dealy, J. M., Wissbrun, K. F.: Melt Rheology and Its Role in Plastics Processing – Theory and Applications, Van Nostrand Reinhold, New York (1990) PMid:11941053; 10.1007/978-1-4615-9738-4Search in Google Scholar

Dealy, J. M., Larson, R. G.: Structure and Rheology of Molten Polymers–From Structure to Flow Behavior and Back Again, Hanser, Munich (2006) PMid:16226436; 10.3139/9783446412811Search in Google Scholar

Friesenbichler, W., Duretek, I., Rajganesh, J. and Ramesh Kumar, S., “Measuring the Pressure Dependent Viscosity at High Shear Rates Using a New Rheological Injection Mould”, Polimery, 56, 5862 (2011)10.14314/polimery.2011.058Search in Google Scholar

Goubert, A., Vermant, J., Moldenaers, P., Göttfert, A. and Ernst, B., “Comparison of Measurement Techniques for Evaluating the Pressure Dependency of Viscosity”, Appl. Rheol., 11, 2637 (2001).10.1515/arh-2001-0003Search in Google Scholar

Hannachi, A., Mitsoulis, E., “Sheet Coextrusion of Polymer Solutions and Melts: Comparison Between Simulation and Experiments”, Adv. Polym. Technol., 12, 217231 (1993) 10.1002/adv.1993.060120301Search in Google Scholar

Hatzikiriakos, S. G., Mitsoulis, E., “Excess Pressure Losses in the Capillary Flow of Molten Polymers”, Rheol. Acta, 35, 545555 (1996) 10.1007/BF00396506Search in Google Scholar

Kajiwara, T., Barakos, G. and Mitsoulis, E., “Rheological Characterization of Polymer Solutions and Melts with an Integral Constitutive Equation”, Int. J. Polymer Anal. Charact., 1, 201215 (1995) 10.1080/10236669508233875Search in Google Scholar

Kazatchkov, I. B., Hatzikiriakos, S. G. and Stewart, C. W., “Extrudate Distortion in the Capillary/Slit Extrusion of a Molten Polypropylene”, Polym. Eng. Sci., 35, 18641871 (1995) 10.1002/pen.760352305Search in Google Scholar

Laun, H. M., “Polymer Melt Rheology with a Slit Die”, Rheol. Acta, 22, 171185 (1983) 10.1007/BF01332370Search in Google Scholar

Laun, H. M., “Pressure Dependent Viscosity and Dissipative Heating in Capillary Rheometry of Polymer Melts”, Rheol. Acta, 42, 295308 (2003) 10.1007/s00397-002-0291-6Search in Google Scholar

Laun, H. M., “Capillary Rheometry for Polymer Melts Revisited”, Rheol. Acta, 43, 509528 (2004) 10.1007/s00397-004-0387-2Search in Google Scholar

Luo, X.-L., Mitsoulis, E., “An Efficient Algorithm for Strain History Tracking in Finite Element Computations of Non-Newtonian Fluids with Integral Constitutive Equations”, Int. J. Num. Meth. Fluids, 11, 10151031 (1990) 10.1002/fld.1650110708Search in Google Scholar

Luo, X. L., Tanner, R. I., “A Streamline Element Scheme for Solving Viscoelastic Flowproblems Part II: Integral Constitutive Models”, J. Non-Newtonian Fluid Mech., 22, 6189 (1986) 10.1016/0377-0257(86)80004-0Search in Google Scholar

Luo, X. L., Tanner, R. I., “A Pseudo-Time Integral Method for Non-Isothermal Viscoelastic Flows and its Application to Extrusion Simulation”, Rheol. Acta, 26, 499507 (1987) 10.1007/BF01333733Search in Google Scholar

Luo, X. L., Tanner, R. I., “Finite Element Simulation of Long and Short Circular Die Extrusion Experiments Using Integral Models”, Int. J. Num. Meth. Eng., 25, 922 (1988) 10.1002/Nme.1620250104Search in Google Scholar

Mitsoulis, E., “Chapter 4. Computational Polymer Processing”, in Modeling and Simulation in Polymers, Gujrati, P. D., Leonov, A.I. (Eds.), Wiley-VCH Verlag, Weinheim, Germany, p. 127195 (2010) 10.1002/9783527630257.ch4Search in Google Scholar

Mitsoulis, E., Hatzikiriakos, S. G., Christodoulou, K. and Vlassopoulos, D., “Sensitivity Analysis of the Bagley Correction to Shear and Extensional Rheology”, Rheol. Acta, 37, 438448 (1998) 10.1007/s003970050131Search in Google Scholar

Mitsoulis, E., Hatzikiriakos, S. G., “Bagley Correction: the Effect of Contraction Angle and its Prediction”, Rheol. Acta42, 309320 (2003) 10.1007/S00397-003-0294-YSearch in Google Scholar

Mitsoulis, E., Hatzikiriakos, S. G., “Steady Flow Simulations of Compressible PTFE Paste Extrusion under Severe Wall Slip”, J. Non-Newtonian Fluid Mech., 157, 2633 (2009) 10.1016/j.jnnfm.2008.09.003Search in Google Scholar

Mitsoulis, E., Kazatchkov, I. B. and Hatzikiriakos, S. G., “The Effect of Slip on the Flow of a Branched PP Melt: Visualisation Experiments and Simulations”, Rheol. Acta, 44, 418426 (2005) 10.1007/s00397-004-0423-2Search in Google Scholar

Mitsoulis, E., Wagner, R. and Heng, F. L., “Numerical Simulation of Wire-Coating Low-Density Polyethylene: Theory and Experiments”, Polym. Eng. Sci., 28, 291310 (1988) 10.1002/pen.760280505Search in Google Scholar

Padmanabhan, M., Macosco, C. W., “Extensional Viscosity from Entrance Pressure Drop Measurements”, Rheol. Acta, 36, 144151 (1997) 10.1007/BF00366820Search in Google Scholar

Papanastasiou, A. C., Scriven, L. E. and Macosko, C. W., “An Integral Constitutive Equation for Mixed Flows: Viscoelastic Characterization”, J. Rheol., 27, 387410 (1983) 10.1122/1.549712Search in Google Scholar

Sedlacek, T., Zatloukal, M., Filip, P., Boltizar, A. and Saha, P., “On the Effect of Pressure on the Shear and Elongational Viscosities of Polymer Melts”, Polym. Eng. Sci., 44, 13281337 (2004) 10.1002/pen.20128Search in Google Scholar

Son, Y., “Measurement of Pressure Dependence on the Shear Viscosity of Polymer Melts”, J. Polym. Res., 16, 667671 (2009)10.1007/s10965-009-9271-1Search in Google Scholar

Tanner, R. I.: Engineering Rheology, 2nd Ed., Oxford University Press, Oxford (2000)Search in Google Scholar

Winter, H. H., “Viscous Dissipation in Shear Flows of Molten Polymers”, Adv. Heat Transfer, 13, 205267 (1977) 10.1016/S0065-2717(08)70224-7Search in Google Scholar

Received: 2017-09-11
Accepted: 2017-12-28
Published Online: 2018-11-16
Published in Print: 2018-11-19

© 2018, Carl Hanser Verlag, Munich

This work is licensed under the Creative Commons Attribution 4.0 International License.

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