Abstract
Isothermal melt spinning experiments have been conducted using two polyethylene melts of low density (LDPE) and high density (HDPE) to produce steady state spinline profiles. The data revealed the threadline extensional viscosity exhibiting a contrasting picture : extension thickening behavior for LDPE and extension thinning one for HDPE. A White-Metzner model having a strain rate-dependent relaxation time was then found to be able to simulate this dichotomy in melt spinning fairly well: the fluids whose relaxation times have smaller strain rate-dependence can fit LDPE data with extension thickening extensional viscosity whereas the fluids whose relaxation times have larger strain rate-dependence can fit HDPE data with extension thinning extensional viscosity. This dichotomous nature of viscoelastic fluids is also believed to be able to explain other similar contrasting phenomena exhibited by polymer melts, such as vortex/no vortex in entry flows, cohesive/ductile fracture modes in extension, and more/less stable draw resonance than Newtonian fluids.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Avenas, P., Denn, M. M. and Petrie, C. J. S., “Mechanics of Steady Spinning of a Viscoelastic Liquid”,AIChE J.,22, 791(1975).
Bagley, E. B. and Birks, A. M., “Flow of Polyethylene into a Capillary”,J. Appl. Physics,31, 556 (1960).
Ballenger, T. F. and White, J. L., “The Development of the Velocity Field in Polymer Melts in a Reservoir Approaching a Capillary Die”,J. Appl. Polym., Sci.,15, 1949 (1971).
Binding, D.M., “An Approximate Analysis for Contraction and Converging Flows”,J. Non-Newtonian Fluid Meck.,27, 173 (1988).
Chen, I.-J., Hagler, G. E., Abbott, L. E., Bouge, D. C. and White, J. L., “Interpretation of Tensile and Melt Spinning Experiments on Low Density and High Density Polyethylene”,Trans, of Soc. of Rheol.,16, 473 (1972).
Hyun, J. C. and Ballman, R. L., “Isothermal Melt Spinning-Lagrangian and Eulerian Viewpoints”,J. Rheol,22, 349 (1978).
Ide, Y. and White, J. L., “Investigation of Failure during Elongational Low of Polymer Melts”,J. Non-Newtonian Fluid Mech.,2, 281 (1977).
Ide, Y. and White, J. L. “Experimental Study of Elongational Flow and Failure of Polymer Melts”,J Appl. Polym. SÄ.,22, 1061 (1978).
Kanai, T. and White, J. L., “Kinematics, Dynamics and Stability of the Tubular Film Extrusion of Various Polyethylenes”,Polym. Eng. Sci.,24, 1185 (1984).
Luo, X.-L. and Mitsoulis, “A Numerical Study of the Effect of Elongational Viscosity on Vortex Growth in Contraction Flows of Polyethylene Melts”,J. Rheol.,34, 309 (1990).
Minoshima, W. and White, J. L., “A Comparative Experimental Study of the Isothermal Shear and Uniaxial Elongational Rheological Properties of Low Density, High Density and Linear Low Density Polyethylenes”,J. Non-Newtonian Fluid Mech.,19, 251 (1986).
Minoshima, W. and White, J. L., “Instability Phenomena in Tubular Film, Melt Spinning of Rheologically Characterized High Density, Low Density and Linear Low Density Polyethylenes”,J. Non-Newtonian Fluid Mech.,19, 275 (1986).
White, S. A., Gotsis, A. D. and Baird, D. G., “Review of the Entry Flow Problem: Experimental and Numerical”,J.Non-Newtonian Fluid Mech.,24, 121 (1987).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Lee, S., Kim, B.M. & Hyun, J.C. Dichotomous behavior of polymer melts in isothermal melt spinning. Korean J. Chem. Eng. 12, 345–351 (1995). https://doi.org/10.1007/BF02705767
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02705767