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Entangled polymers

JUN 01, 1983
A theory based on the snake‐like motion by which chains of monomers move in the melt is enhancing our understanding of rheology, diffusion, polymer–polymer welding, chemical kinetics and biotechnology.

DOI: 10.1063/1.2915700

Pierre‐Gilles de Gennes

Most of us have played with lumps of “silly putty,” the strange substance shown in the photographs on page 34. Given a bit of time, this material flows like a viscous liquid. Forced to respond quickly, it bounces like rubber. We can trace this “viscoelastic” behavior, which shows up in all polymer melts, to the knotting of the chains of “monomers” that make up the polymers. Shearing forces tend to undo certain knots, but this takes a finite time τ. In a time greater than τ the original knots fade out, and the melt flows. Over shorter times the original knots are all present, and the melt behaves like an elastic network.

References

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  2. 2. For a physical approach to the classification of knots, see R. Ball, M. Mehta, Journ. Phys. (Paris) 42, 1193 (1981).https://doi.org/JOPQAG

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  12. 12. F. Brochard, P. G. de Gennes, Physiochemical Hydrodynamics, to be published.

  13. 13. See, for instance, I. Mita, K. Horie, M. Takeda, Macromolecules 14, 1428 (1981); https://doi.org/MAMOBX
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  16. 16. P. G. de Gennes in Microscopic Aspects of Adhesion and Lubrication, J. M. Georges, ed., Elsevier, Amsterdam (1982), page 355;
    Detailed calculations on the interdigitation profile are given by M. Tirrel, S. Prager, J. Chem. Phys. 10, 5194 (1981).https://doi.org/JCPSA6

  17. 17. R. P. Wool, ACS Polymer Preprints 23 (2), 62 (1982).

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  19. 19. P. G. de Gennes, C. R. Acad. Sci. (Paris) 294 II, 827 (1982).

  20. 20. S. Alexander, J. Bernasconi, W. Schneider, R. Orbach, in Physics in One Dimension, Springer‐Verlag, New York, solid state series 23 (1981), page 277.

  21. 21. F. Brochard, J. Jouffroy, P. Levinson, Macromolecules, to be published.

More about the Authors

Pierre‐Gilles de Gennes. College de France.

This Content Appeared In
pt-cover_1983_06.jpeg

Volume 36, Number 6

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