Scitation | Help | Feedback
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 
Journal of Rheology / Volume 46 / Issue 2

J. Rheol. 46, 529 (2002); http://dx.doi.org/10.1122/1.1446883 (26 pages)

Effects of shear flow on a polymeric bicontinuous microemulsion: Equilibrium and steady state behavior

Kasiraman Krishnan, Bryan Chapman, Frank S. Bates, and Timothy P. Lodge

Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455

Kristoffer Almdal

Risø National Laboratory, DK-4000 Roskilde, Denmark

Wesley R. Burghardt

Department of Chemical Engineering, Northwestern University, Evanston, Illinois 60208

Full Text: Read Online (HTML) | Download PDF FREE | View Cart
We have investigated the effects of shear flow on a polymeric bicontinuous microemulsion using neutron scattering, light scattering, optical microscopy, and rheology. The microemulsion consists of a ternary blend of poly(ethyl ethylene) (PEE), poly(dimethyl siloxane) (PDMS), and a PEE–PDMS diblock copolymer. At equilibrium, the microemulsion contains two percolating microphases, one PEE rich and the other PDMS rich, separated by a copolymer-laden interface; the characteristic length scale of this structure is 80 nm. Low strain amplitude oscillatory shear measurements reveal behavior similar to that of block copolymer lamellar phases just above the order–disorder transition. Steady shear experiments expose four distinct regimes of response as a function of the shear rate. At low shear rates (regime I) Newtonian behavior is observed, whereas at intermediate shear rates (regime II) development of anisotropy in the morphology leads to shear thinning. When the shear rate is further increased, there is an abrupt breakdown of the bicontinuous structure, resulting in flow-induced phase separation (regime III). Rheological measurements indicate that the shear stress is almost independent of the shear rate in this regime. Light scattering reveals a streak-like pattern, and correspondingly a string-like morphology with micron dimensions is observed with video microscopy. Upon a further increase of the shear rate (regime IV), the sample resembles an immiscible binary polymer blend with the block copolymer playing no significant role; the stress increases strongly with the shear rate. In some respects these results resemble those from other weakly structured complex fluids (sponge phases, liquid crystals, worm-like micelles, block copolymers, polymer blends, and polymer solutions), yet in important ways this system is unique. © 2002 The Society of Rheology.

© 2002 The Society of Rheology

KEYWORDS and PACS

Keywords

polymer blends, polymer solutions, phase separation, microemulsions, viscosity, light scattering, shear flow, rheology, optical microscopy, neutron diffraction, Microemulsion, Blends, Emulsions

PACS

  • 83.80.Rs

    Polymer solutions

  • 83.80.Iz

    Emulsions and foams

  • 83.60.Fg

    Shear rate dependent viscosity

  • 83.60.Rs

    Shear rate-dependent structure (shear thinning and shear thickening)

PUBLICATION DATA

ISSN

0148-6055 (print)  

Publisher

The Society of Rheology

RELATED DATABASES

Web of Science

View this record in Web of Science

View Web of Science related articles

ARTICLE DATA

History
Received 13 Aug 01
Revised 27 Nov 01
Digital Object Identifier
http://dx.doi.org/10.1122/1.1446883

  1. Almdal, K., J. H. Rosedale, and F. S. Bates, "The order–disorder transition in binary mixtures of nearly symmetric diblock copolymers," Macromolecules 23, 4336–4338 (1990). [ISI]
  2. Anklam, M. R., R. K. Prud'homme, and G. G. Warr, "Shear thinning in ternary bicontinuous and water-in-oil microemulsions," AIChE J. 41, 677–682 (1995). [ISI]
  3. Bates, F. S., W. W. Maurer, P. M. Lipic, M. A. Hillmyer, K. S. Almdal, K. Mortensen, G. H. Fredrickson, and T. P. Lodge, "Polymeric bicontinuous microemulsions," Phys. Rev. Lett. 79, 849–852 (1997). [ISI]
  4. Berret, J.-F., D. C. Roux, and P. Lindner, "Structure and rheology of concentrated wormlike micelles at the shear-induced isotropic-to-nematic transition," Eur. Phys. J. B 5, 67–77 (1998). [Inspec] [ISI]
  5. Berret, J.-F., D. C. Roux, and G. Porte, "Isotropic to nematic transition in wormlike micelles under shear," J. Phys. II 4, 1261–1279 (1994). [Inspec] [ISI]
  6. Cates, M. E., "Reptation of living polymers—Dynamics of entangled polymers in the presence of reversible chain-scission reactions," Macromolecules 20, 2289–2296 (1987). [ISI]
  7. Cates, M. E. and S. T. Milner, "Role of shear in isotropic-to-lamellar transition," Phys. Rev. Lett. 62, 1856–1859 (1989). [MEDLINE]
  8. Chen, C.-M. and G. G. Warr, "Rheology of ternary microemulsions," J. Phys. Chem. 96, 9492–9497 (1992). [Inspec] [ISI]
  9. Chen, Z. J., M. T. Shaw, and R. A. Weiss, "Explanation of `dark-streak' light scattering patterns and shear-induced structure development of phase-separated polymer blends," Macromolecules 28, 648–650 (1995). [ISI]
  10. Chopra, D., D. Vlassopoulos, and S. G. Hatzikiriakos, "Shear-induced mixing and demixing in poly(styrene-co-maleic anhydride)/poly(methyl methacrylate) blends," J. Rheol. 42, 1227–1247 (1998)JORHD2000042000005001227000001. [ISI]
  11. Cox, W. P. and E. H. Merz, "Correlation of dynamic and steady flow viscosities," J. Polym. Sci. 28, 619–621 (1958).
  12. Fernandez, M. L., J. S. Higgins, and M. Richardson, "Flow instabilities in polymer blends under shear," Polymer 36, 931–939 (1995). [Inspec] [ISI]
  13. Fredrickson, G. H., "Steady shear alignment of block copolymers near the isotropic-lamellar transition," J. Rheol. 38, 1045–1067 (1994)JORHD2000038000004001045000001.
  14. Fredrickson, G. H. and F. S. Bates, "Design of bicontinuous polymeric microemulsions," J. Polym. Sci., Part B: Polym. Phys. 35, 2775–2786 (1997). [ISI]
  15. Gerard, H., J. S. Higgins, and N. Clarke, "Shear-induced demixing in poly(styrene)/poly(vinyl methyl ether) blends. 1. Early stages of shear-induced demixing," Macromolecules 32, 5411–5422 (1999). [ISI]
  16. Gompper, G. and M. Schick, Phase Transitions and Critical Phenomena (Academic, London, 1994), Vol. 16.
  17. Gupta, V. K., R. Krishnamoorti, J. A. Kornfield, and S. D. Smith, "Evolution of microstructure during shear alignment in a polystyrene-polyisoprene lamellar diblock copolymer," Macromolecules 28, 4464–4474 (1995). [ISI]
  18. Han, C. D., D. M. Baek, J. K. Kim, T. Ogawa, N. Sakamoto, and T. Hashimoto, "Effect of volume fraction on the order–disorder transition in low molecular weight polysterene-block-polyisoprene copolymers. 1. Order–disorder transition temperature determined by rheological measurements," Macromolecules 28, 5043–5062 (1995). [ISI]
  19. Hashimoto, T., T. Takebe, and S. Suchiro, "Ordered structure and critical phenomena of a semidilute solution of polymer mixtures under shear flow," J. Chem. Phys. 88, 5874–5881 (1988)JCPSA6000088000009005874000001.
  20. Hillmyer, M. A., W. W. Maurer, T. P. Lodge, F. S. Bates, and K. Almdal, "Model bicontinuous microemulsions in ternary homopolymer/block copolymer blends," J. Phys. Chem. B 103, 4814–4824 (1999). [ISI]
  21. Hindawi, I. A., J. S. Higgins, and R. A. Weiss, "Flow-induced mixing and demixing in polymer blends," Polymer 33, 2522–2529 (1992). [ISI]
  22. Hong, Z., M. T. Shaw, and R. A. Weiss, "Effect of shear flow on the morphology and phase behavior of a near-critical SAN/PMMA blend," Macromolecules 31, 6211–6216 (1998). [ISI]
  23. Hong, Z., M. T. Shaw, and R. A. Weiss, "Structure evolution and phase behavior of polymer blends under the influence of shear," Polymer 41, 5895–5902 (2000). [Inspec] [ISI]
  24. Jin, X. and T. P. Lodge, "Fluctuation regime in the viscoelastic properties of block copolymer solutions," Rheol. Acta 36, 229–238 (1997). [ISI]
  25. Kielhorn, L. and M. Muthukumar, "Fluctuation theory of diblock copolymer/homopolymer blends and its effects on the Lifshitz point," J. Chem. Phys. 107, 5588–5608 (1997)JCPSA6000107000014005588000001.
  26. Kielhorn, L., R. H. Colby, and C. C. Han, "Relaxation behavior of polymer blends after the cessation of shear," Macromolecules 33, 2486–2496 (2000). [ISI]
  27. Kim, S., E. K. Hobbie, J.-W. Yu, and C. C. Han, "Droplet breakup and shear-induced mixing in critical polymer blends," Macromolecules 30, 8245–8253 (1997). [ISI]
  28. Koppi, K. A., M. Tirrell, F. S. Bates, K. Almdal, and R. H. Colby, "Lamellae orientation in dynamically sheared diblock copolymer melts," J. Phys. II 2, 1941–1959 (1992).
  29. Koppi, K. A., M. Tirrell, and F. S. Bates, "Shear-induced isotropic-to-lamellar transition," Phys. Rev. Lett. 70, 1449–1452 (1993). [MEDLINE]
  30. Krishnan, K., K. Almdal, T. P. Lodge, F. S. Bates, and W. R. Burghardt, "Shear-induced nano–macrostructural transition in a polymeric bicontinuous microemulsion," Phys. Rev. Lett. 87, 098301/1–098301/4 (2001). [MEDLINE]
  31. Kume, T., T. Hattori, and T. Hashimoto, "Time evolution of shear-induced structures in semidilute polystyrene blends," Macromolecules 30, 427–434 (1997). [ISI]
  32. Mahjoub, H. F., C. Bourgaux, P. Sergot, and M. Kleman, "Evidence of a sponge-to-lamellar phase transition under shear by x-ray scattering experiments in a couette cell," Phys. Rev. Lett. 81, 2076–2079 (1998). [ISI]
  33. Martys, N. S. and J. F. Douglas, "Critical properties and phase separation in lattice Boltzmann fluid mixtures," Phys. Rev. E 63, 031205/1–031205/18 (2001).
  34. Matsen, M. W., "Elastic properties of a diblock copolymer monolayer and their relevance to bicontinuous microemulsion," J. Chem. Phys. 110, 4658–4667 (1999)JCPSA6000110000009004658000001.
  35. Menasveta, M. J. and D. A. Hoagland, "Light scattering from dilute poly(styrene) solutions in uniaxial elongational flow," Macromolecules 24, 3427–3433 (1991). [ISI]
  36. Migler, K., C.-H. Liu, and D. J. Pine, "Structure evolution of a polymer solution at high shear rates," Macromolecules 29, 1422–1432 (1996). [ISI]
  37. Miles, I. S. and A. Zurek, "Preparation, structure, and properties of two-phase co-continuous polymer blends," Polym. Eng. Sci. 28, 796–805 (1988). [ISI]
  38. Morkved, T. L., B. R. Chapman, F. S. Bates, and T. P. Lodge, "Dynamics of ternary polymer blends: Disordered, ordered and bicontinuous microemulsion phases," Faraday Discuss. 112, 335–350 (1999). [ISI]
  39. Morkved, T. L., P. Stepanek, K. Krishnan, F. S. Bates, and T. P. Lodge, "Static and dynamic scattering from ternary polymer blends: Lifshitz lines, disorder lines and bicontinuous microemulsion," J. Chem. Phys. 114, 7247–7259 (2001)JCPSA6000114000016007247000001. [ISI]
  40. Moses, E., T. Kume, and T. Hashimoto, "Shear microscopy of the `butterfly pattern' in polymer mixtures," Phys. Rev. Lett. 72, 2037–2040 (1994). [ISI] [MEDLINE]
  41. Nakatani, A. I., L. Sung, E. K. Hobbie, and C. C. Han, "Shear-induced order in a homopolymer blend with a block copolymer surfactant," Phys. Rev. Lett. 79, 4693–4696 (1997). [ISI]
  42. Nakatani, A. I., H. Kim, Y. Takahashi, Y. Matsushita, A. Takano, B. Bauer, and C. C. Han, "Shear stabilization of critical fluctuations in bulk polymer blends studied by small-angle neutron scattering," J. Chem. Phys. 93, 795–810 (1990)JCPSA6000093000001000795000001.
  43. Olmsted, P. D., "Two-state shear diagrams for complex fluids in shear flow," Europhys. Lett. 48, 339–345 (1999).
  44. Olmsted, P. D. and C.-Y. D. Lu, "Co-existence and phase separation in sheared complex fluids," Phys. Rev. E 56, R55–R58 (1997).
  45. Pätzold, G. and K. Dawson, "Connection of microstructure to rheology in a microemulsion model," Phys. Rev. E 54, 1669–1682 (1996). [MEDLINE]
  46. Rosedale, J. H. and F. S. Bates, "Rheology of ordered and disordered symmetric poly(ethylenepropylene)-poly(ethylethylene) diblock copolymers," Macromolecules 23, 2329–2338 (1990).
  47. Schubert, K. V., R. Strey, S. R. Kline, and E. W. Kaler, "Small angle neutron scattering near Lifshitz lines: Transition from weakly structured mixtures to microemulsions," J. Chem. Phys. 101, 5343–5355 (1994)JCPSA6000101000006005343000001.
  48. Scriven, L. E., "Equilibrium bicontinuous structure," Nature (London) 263, 123–125 (1976).
  49. Spenley, N. A., M. E. Cates, and T. C. B. McLeish, "Nonlinear rheology of wormlike micelles," Phys. Rev. Lett. 71, 939–942 (1993). [MEDLINE]
  50. Tepe, T., D. A. Hajduk, M. A. Hillmyer, P. A. Weimann, M. Tirrell, and F. S. Bates, "Influence of shear on a lamellar triblock copolymer near the order–disorder transition," J. Rheol. 41, 1147–1171 (1997)JORHD2000041000005001147000001. [ISI]
  51. Teubner, M. and R. Strey, "Origin of scattering peak in microemulsions," J. Chem. Phys. 87, 3195–3200 (1987)JCPSA6000087000005003195000001.
  52. Thevenin, M. A. B., J. L. Grossiord, and M. C. Poelman, "Characterization of a sucrose ester microemulsion by freeze fracture electron micrograph and small angle neutron scattering experiments," Langmuir 15, 2307–2315 (1999). [ISI]
  53. Veenstra, H., B. J. J. van Lent, J. van Dam, and A. P. de Boer, "Co-continuous morphologies in polymer blends with SEBS block copolymers," Polymer 40, 6661–6672 (1999). [ISI]
  54. Vigild, M. E., C. Chu, M. Sugiyama, K. A. Chaffin, and F. S. Bates, "Influence of shear on the alignment of a lamellae-forming pentablock copolymer," Macromolecules 34, 951–964 (2001). [ISI]
  55. Warr, G. G., "Shear and elongational rheology of ternary microemulsions," Colloids Surf., A 103, 273–279 (1995). [ISI]
  56. Washburn, N. R., T. P. Lodge, and F. S. Bates, "Ternary polymer blends as model surfactant systems," J. Phys. Chem. B 104, 6987–6997 (2000). [ISI]
  57. Yamamoto, J. and H. Tanaka, "Shear-induced sponge-to-lamellar transition in a hyperswollen lyotropic system," Phys. Rev. Lett. 77, 4390–4393 (1996). [MEDLINE]


Close
   

Your Recent History Recent History Help

Recently Viewed

  1. Effects of shear flow on a polymeric bicontinuous microemulsion: Equilibrium and steady state behavior
  2. Slip at polymer–polymer interfaces: Rheological measurements on coextruded multilayers
  3. Rheology and nuclear magnetic resonance measurements under shear of sodium dodecyl sulfate/decanol/water nematics
  4. Pressure and temperature effects in slit rheometry
  5. Molecular constitutive equations for a class of branched polymers: The pom-pom polymer
©  The Society of Rheology
close