Rheologica Acta

, Volume 49, Issue 10, pp 985–991 | Cite as

Elastic yielding after step shear and during LAOS in the absence of meniscus failure

Original Contribution

Abstract

This work examines the possibility that the previously observed elastic yielding, i.e., nonquiescent relaxation after a large step shear (Ravindranath and Wang, Macromolecules 40:8031–8039, 2007) is due to an intrinsic experimental difficulty technically known as edge fracture. By redesigning the rheometric apparatus to eliminate edge failure, we show by an example of a well-entangled polymer solution that elastic yielding still occurs in the absence of any edge failure. We are also able to confirm that shear banding during large amplitude oscillatory shear (Ravindranath and Wang, J Rheol 52:341–358, 2008a) is an inherent rheological characteristic related to internal yielding of the entanglement network.

Keywords

Elastic yielding Step strain Nonquiescent relaxation Edge fracture Nonlinear rheology 

References

  1. Adams JM, Olmsted PD (2009a) Nonmonotonic models are not necessary to obtain shear banding phenomena in entangled polymer solutions. Phys Rev Lett 102:067801CrossRefADSGoogle Scholar
  2. Adams JM, Olmsted PD (2009b) Comment on “nonmonotonic models are not necessary to obtain shear banding phenomena in entangled polymer solutions”. Phys Rev Lett 103:219801 (author reply)CrossRefADSGoogle Scholar
  3. Boukany PE, Wang SQ (2009a) Shear banding or not in entangled DNA solutions depending on the level of entanglement. J Rheol 53:73–83CrossRefADSGoogle Scholar
  4. Boukany PE, Wang SQ (2009b) Exploring the transition from wall slip to bulk shearing banding in well-entangled DNA solutions. Soft Matter 5:780–789CrossRefGoogle Scholar
  5. Boukany PE, Hu YT, Wang SQ (2008) Observations of wall slip and shear banding in an entangled DNA solution. Macromolecules 41:2644–2650CrossRefADSGoogle Scholar
  6. De Gennes PG (2007) Melt fracture of entangled polymers. Eur Phys J E 23:3–5CrossRefGoogle Scholar
  7. Doi M, Edwards SF (1988) The theory of polymer dynamics, 2nd edn. Oxford University Press, New YorkGoogle Scholar
  8. Ferry JD (1980) Viscoelastic properties of polymers. Wiley, New YorkGoogle Scholar
  9. Galvin PT, Whorlow RW (1975) Studies of time effects in the flow of polymer melts using a biconical viscometer. J Appl Polym Sci 19:567–583CrossRefGoogle Scholar
  10. Graham RS, Likhtman AE, McLeish TCB (2003) Microscopic theory of linear, entangled polymer chains under rapid deformation including chain stretch and convective constraint release. J Rheol 47:1171–1200CrossRefADSGoogle Scholar
  11. Inn YW, Wissbrun KF, Denn MM (2005) Effect of edge fracture on constant torque rheometry of entangled polymer solutions. Macromolecules 38:9385–9388CrossRefADSGoogle Scholar
  12. Lodge AS (1964) Elastic liquids. An introductory vector treatment of finite-strain polymer rheology. Academic, LondonGoogle Scholar
  13. Marrucci G (1996) Dynamics of entanglements: a nonlinear model consistent with the Cox–Merz rule. J Non-Newton Fluid Mech 62:279–289CrossRefGoogle Scholar
  14. Mead DW, Larson RG, Doi M (1998) A molecular theory for fast flows of entangled polymers. Macromolecules 31:7895–7914CrossRefADSGoogle Scholar
  15. Meissner J, Garbella RW, Hostettler J (1989) Measuring normal stress differences in polymer melt shear flow. J Rheol 33:843–864CrossRefGoogle Scholar
  16. Ravindranath S, Wang SQ (2007) What are the origins of stress relaxation behaviors in step shear entangled polymer solutions. Macromolecules 40:8031–8039CrossRefADSGoogle Scholar
  17. Ravindranath S, Wang SQ (2008a) Particle-tracking velocimetric investigation of large amplitude oscillatory shear behavior of entangled polymer solutions. J Rheol 52:341–358CrossRefADSGoogle Scholar
  18. Ravindranath S, Wang SQ (2008b) Banding in simple steady shear of entangled polymer solutions. Macromolecules 41:2663–2670CrossRefADSGoogle Scholar
  19. Ravindranath S, Wang SQ (2008c) Steady state measurements in stress plateau region of entangled polymer solutions: controlled-rate and controlled-stress modes. J Rheol 52:957–980CrossRefADSGoogle Scholar
  20. Schweizer T (2002) Measurement of the first and second normal stress differences in a polystyrene melt with a cone and partitioned plate tool. Rheol Acta 41:337–344CrossRefGoogle Scholar
  21. Schweizer T (2007) Shear banding during nonlinear creep with a solution of monodisperse polystyrene. Rheol Acta 46:629–637CrossRefGoogle Scholar
  22. Sui C, McKenna GB (2007) Instability of entangled polymers in cone and plate rheometry. Rheol Acta 46:877–888CrossRefGoogle Scholar
  23. Tapadia P, Wang SQ (2006) Direct visualization of continuous simple shear in non-Newtonian polymeric fluids. Phys Rev Lett 96:016001–004ADSGoogle Scholar
  24. Wang SQ (2009) Comment on “nonmonotonic models are not necessary to obtain shear banding phenomena in entangled polymer solutions”. Phys Rev Lett 103:219801–1 (Adams and Olmsted replied to our comment by carrying out a simulation with a “homogeneous” step strain of 3.0 that produces sinusoidal wave-like macroscopic motion after shear cessation in Fig. 2 (Adams and Olmsted 2009b). However, this starting condition is anything but homogeneous shear. Velocity field and therefore the deformation field were not completely a linear function of the gap distance in their Fig. 2)Google Scholar
  25. Wang SQ, Ravindranath S, Boukany PE, Olechnowicz M, Quirk RP, Halasa A, Mays J (2006) Nonquiescent relaxation in entangled polymer liquids after step shear. Phys Rev Lett 97:187801–804ADSGoogle Scholar
  26. Wang YY, Wang SQ (2009) Yielding during startup deformation of entangled linear polymeric liquids. J Rheol 53:1389CrossRefADSGoogle Scholar
  27. Wang YY, Boukany PE, Wang SQ, Wang XR (2007) Elastic breakup in uniaxial extension of entangled polymer melts. Phys Rev Lett 99:237801–804ADSGoogle Scholar

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  1. 1.Department of Polymer ScienceUniversity of AkronAkronUSA

Personalised recommendations