The European Physical Journal E

, Volume 17, Issue 3, pp 247–259 | Cite as

Chain orientation in natural rubber, Part I: The inverse yielding effect

Original Article


Inhomogeneous deformations are observed in stretched natural rubber of different crosslink density; the conditions of observation, nucleation and propagation are given in the first part of the paper. In samples of low crosslink density these inhomogeneities recall necking observed in others materials and in glassy polymers when the materials are drawn above a critical draw ratio. The difference is that in natural rubbers, NR, they nucleate and propagate at constant stress during unloading. This phenomenon, called inverse yielding appears during recovery only if the samples have been drawn previously in the hardening domain. During necking propagation the stress is constant. The mechanical and crystallinity properties of samples with and without inverse yielding are studied as a function of draw ratio, crosslink density and temperature. In the second part of the paper this transition zone (neck) of thickness 2 mm is studied by WAXS at the synchrotron source. From the orientation of NR crystallites and from the orientation of the stearic acid (2%, present in this type of rubber) we conclude that the deformation in the neck follows the flow lines. From the local crystallinity of the NR crystallites one deduces the local draw ratio across this transition zone. We suggest that in all these rubbers, which present a plateau of the recovery stress strain curve, micronecking exists. This effect is discussed in the framework of the Flory theory.-1


62.20.Fe Deformation and plasticity (including yield, ductility, and superplasticity) 61.41.+e Polymers, elastomers, and plastics 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    P.J. Flory, Principle of Polymer Chemistry (Cornell University Press, 1953).Google Scholar
  2. 2.
    L.R.G. Treloar, The Physics of Rubber Elasticity (Oxford University Press, Oxford, 1975).Google Scholar
  3. 3.
    J.E. Mark, B. Erman, F.R. Eirich, Science and Technology of Rubber, second edition (Academic Press, San Diego, 1994).Google Scholar
  4. 4.
    A.N. Gent, S. Kawahara, J. Zhao, Rubber Chem. Technol. 71, 668 (1998).Google Scholar
  5. 5.
    S. Toki, I. Sics, S. Ran, L. Liu, B.S. Hsiao, S. Murakami, K. Senoo, S. Kohjiya, Macromolecules 35, 6573 (2002).CrossRefGoogle Scholar
  6. 6.
    S. Trabelsi, P.A. Albouy, J. Rault, Macromolecules 36, 7624 (2003),CrossRefGoogle Scholar
  7. 7.
    Y. Miyamoto, H. Yamao, K. Sekimoto, Macromolecules 36, 6462 (2003).CrossRefGoogle Scholar
  8. 8.
    S. Trabelsi, P.A. Albouy, J. Rault, Macromolecules 35, 10054 (2002).CrossRefGoogle Scholar
  9. 9.
    S. Trabelsi, Thesis, Orsay (2002).Google Scholar
  10. 10.
    H.P. Klug, L.E. Alexander, in X-ray Diffraction Procedures (Wiley, New York, 1954).Google Scholar
  11. 11.
    H. Lavebratt, B. Stenberg, P.E. Werner, Polymer 34, 1109 (1993).CrossRefGoogle Scholar
  12. 12.
    G.R. Mitchell, Polymer 25, 1562 (1984).CrossRefGoogle Scholar
  13. 13.
    S. Trabelsi, P.A. Albouy, J. Rault, Rubber Chem. Technol. 77, 303 (2004).Google Scholar
  14. 14.
    A.N. Gent, Trans. Faraday Soc. 50, 521 (1954)CrossRefGoogle Scholar
  15. 15.
    H.G. Kim, L. Mandelkern, J. Polym. Sci. A2 6, 181 (1968).CrossRefGoogle Scholar
  16. 16.
    A.N. Gent, L.Q. Zhang, J. Polym. Sci., Polym. Phys. Ed. 39, 811 (2001). CrossRefGoogle Scholar
  17. 17.
    W.R. Krigbaum, R.J. Roe, J. Polym. Sci. A2 439, 1 (1964),Google Scholar
  18. 18.
    R. Kitamaru, H. Dong, W. Tsuji, Macromol. Chem. 8, 98 (1966).Google Scholar
  19. 19.
    R.J. Gaylord, J. Polym. Sci., Polym. Lett. Ed. 13, 337 (1975)CrossRefGoogle Scholar
  20. 20.
    R.J. Gaylord, D. Lohse, J. Polym. Eng. Sci. 16, 163 (1976).CrossRefGoogle Scholar
  21. 21.
    P.J. Flory, J. Chem. Phys. 15, 397 (1947).CrossRefGoogle Scholar
  22. 22.
    K. Smith, J. Polym. Eng. Sci. 16, 168 (1976).CrossRefGoogle Scholar
  23. 23.
    A. Postuma de Boer, A.J. Pennings, Faraday Discuss. Chem. Soc. 68, 345 (1979).CrossRefGoogle Scholar
  24. 24.
    J. Brandrup, E.T. Immergut (Editors), Polymer Handbook (Inter Science Publ., New York, 1965).Google Scholar
  25. 25.
    J. Rault, E. Souffache, J. Polym. Sci. Polym. Phys. Ed. 27, 1349 (1989).CrossRefGoogle Scholar
  26. 26.
    E. Souffache, J. Rault, Macromolecules 22, 3581 (1989).CrossRefGoogle Scholar
  27. 27.
    D. Goritz, Angew. Makromol. Chem. 202/203, 309 (1992).Google Scholar
  28. 28.
    D. Luch, G.S.Y. Yeh, J. Macromol. Sci., Part B Phys. 7, 121 (1973).Google Scholar
  29. 29.
    I.R. Hardin, G.S.Y. Yeh, J. Macromol. Sci., Part B Phys. 7, 393 (1973).Google Scholar
  30. 30.
    Faraday Discuss. Chem. Soc., Vol. 68 (1979).Google Scholar
  31. 31.
    J.D. Ferry, Viscoelastic Properties of Polymers (Wiley, New York, 1961).Google Scholar
  32. 32.
    P. Thirion, R. Chassenet, Rev. Gen. Caoutch. 41, 271 (1964).Google Scholar
  33. 33.
    D.J. Plazek, J. Polym. Sci., Polym. Phys. Ed. 74, 5 (1966).Google Scholar
  34. 34.
    L.C. Struik, Physical Aging in Amorphous Polymers and Others Materials (Elsevier, Amsterdam, 1978).Google Scholar
  35. 35.
    J.M. Drake, J. Klafter, R. Kopelman (Editors), Dynamics in Small Confining Systems (Materials Research Society, Pittsburg, 1990).Google Scholar
  36. 36.
    J.L. Keddie, R.A.L. Jones, R.A. Cory, Europhys. Lett. 27, 59 (1994).Google Scholar
  37. 37.
    J.A. Forrest, K. Dalnoki-Veress, J.R. Dutcher, Phys. Rev. E 56, 5705 (1997).CrossRefGoogle Scholar
  38. 38.
    J. Rault, J. Macromol. Sci., Part B Phys. 42, 1235 (2003).Google Scholar
  39. 39.
    M. Botev, P. Judeinstein, J. Rault, Polymer 40, 5227 (1999).CrossRefGoogle Scholar

Copyright information

© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2005

Authors and Affiliations

  1. 1.Laboratoire de Physique des Solides, UMR 8502Université de Paris-SudOrsayFrance

Personalised recommendations