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Molecular simulation of the swelling of polyelectrolyte gels by monovalent and divalent counterions

J. Chem. Phys. 129, 154902 (2008); doi:10.1063/1.2991179

Published 16 October 2008

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De-Wei Yin,1 Ferenc Horkay,2 Jack F. Douglas,3 and Juan J. de Pablo1
1Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706-1691, USA
2Section on Tissue Biophysics and Biomimetics, Laboratory of Integrative and Medical Biophysics, NICHD National Institutes of Health, Bethesda, Maryland 20892-5772, USA
3Polymers Division, U.S. National Institute of Standards and Technology, Gaithersburg, Maryland 20899-0001, USA
Permanently crosslinked polyelectrolyte gels are known to undergo discontinuous first-order volume phase transitions, the onset of which may be caused by a number of factors. In this study we examine the volumetric properties of such polyelectrolyte gels in relation to the progressive substitution of monovalent counterions by divalent counterions as the gels are equilibrated in solvents of different dielectric qualities. We compare the results of coarse-grained molecular dynamics simulations of polyelectrolyte gels with previous experimental measurements by others on polyacrylate gels. The simulations show that under equilibrium conditions there is an approximate cancellation between the electrostatic contribution and the counterion excluded-volume contribution to the osmotic pressure in the gel-solvent system; these two contributions to the osmotic pressure have, respectively, energetic and entropic origins. The finding of such a cancellation between the two contributions to the osmotic pressure of the gel-solvent system is consistent with experimental observations that the swelling behavior of polyelectrolyte gels can be described by equations of state for neutral gels. Based on these results, we show and explain that a modified form of the Flory–Huggins model for nonionic polymer solutions, which accounts for neither electrostatic effects nor counterion excluded-volume effects, fits both experimental and simulated data for polyelectrolyte gels. The Flory–Huggins interaction parameters obtained from regression to the simulation data are characteristic of ideal polymer solutions, whereas the experimentally obtained interaction parameters, particularly that associated with the third virial coefficient, exhibit a significant departure from ideality, leading us to conclude that further enhancements to the simulation model, such as the inclusion of excess salt, the allowance for size asymmetric electrolytes, or the use of a distance-dependent solvent dielectricity model, may be required. Molecular simulations also reveal that the condensation of divalent counterions onto the polyelectrolyte network backbone occurs preferentially over that of monovalent counterions. ©2008 American Institute of Physics
History: Received 1 May 2008; accepted 5 September 2008; published 16 October 2008
Permalink: http://link.aip.org/link/?JCPSA6/129/154902/1
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KEYWORDS and PACS

Keywords
PACS
  • 61.25.hp
    Polymer swelling, cross-linking
  • 82.39.Wj
    Ion exchange, dialysis, osmosis, electro-osmosis, membrane processes in biological systems
  • 83.80.Rs
    Polymer solutions (rheology)
  • 82.70.Gg
    Gels and sols
  • 82.35.Rs
    Polyelectrolytes (chemistry)
  • YEAR: 2008

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PUBLICATION DATA

ISSN:
0021-9606 (print)   1089-7690 (online)
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REFERENCES (57)
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For access to fully linked references, you need to log in. For access to fully linked references, you need to Log in.
  1. I. Tasaki and P. M. Byrne, Biopolymers 32, 1019 (1992).
  2. Y. Zhang, J. F. Douglas, B. D. Ermi, and E. J. Amis, J. Chem. Phys. 114, 3299 (2001).
  3. T. L. Hill, J. Chem. Phys. 20, 1259 (1952).
  4. Y. Yamasaki and K. Yoshikawa, J. Am. Chem. Soc. 119, 10573 (1997).
  5. M. A. V. Axelos, M. M. Mestdagh, and J. François, Macromolecules 27, 6594 (1994).
  6. P. J. Flory, Principles of Polymer Chemistry (Cornell University Press, Ithaca, NY, 1953).
  7. T. Tanaka, Phys. Rev. Lett. 40, 820 (1978).
  8. T. Tanaka, in Polyelectrolyte Gels, ACS Symposium Series Vol. 480, edited by R. S. Harland and R. K. Prud'homme (American Chemical Society, Washington, DC, 1992), Chap. 1, pp. 1–21.
  9. F. Horkay, I. Tasaki, and P. J. Basser, Biomacromolecules 1, 84 (2000).
  10. C. W. Wolgemuth, A. Mogilner, and G. Oster, Eur. Biophys. J. 33, 146 (2004).
  11. A. Katchalsky and I. Michaeli, J. Polym. Sci. 15, 69 (1955).
  12. K. Dušek and D. Patterson, J. Polym. Sci., Part A-2 6, 1209 (1968).
  13. P. J. Flory, J. Chem. Phys. 21, 162 (1953).
  14. P. J. Flory and J. E. Osterheld, J. Phys. Chem. 58, 653 (1954).
  15. M. Muthukumar, Macromolecules 35, 9142 (2002).
  16. K. Huber, J. Phys. Chem. 97, 9825 (1993).
  17. A. Ikegami and N. Imai, J. Polym. Sci. 56, 133 (1962).
  18. F. Horkay, A. M. Hecht, C. Rochas, P. J. Basser, and E. Geissler, J. Chem. Phys. 125, 234904 (2006).
  19. R. Moerkerke, R. Koningsveld, H. Berghmans, K. Dušek, and K. Šolc, Macromolecules 28, 1103 (1995).
  20. K. Šolc, K. Dušek, R. Koningsveld, and H. Berghmans, Collect. Czech. Chem. Commun. 60, 1661 (1995).
  21. F. Horkay, I. Tasaki, and P. J. Basser, Biomacromolecules 2, 195 (2001).
  22. F. Horkay and P. J. Basser, Biomacromolecules 5, 232 (2004).
  23. D. -W. Yin, Q. Yan, and J. J. de Pablo, J. Chem. Phys. 123, 174909 (2005).
  24. C. N. Patra and A. Yethiraj, J. Phys. Chem. B 103, 6080 (1999).
  25. M. Zrínyi and F. Horkay, J. Polym. Sci., Polym. Phys. Ed. 20, 815 (1982).
  26. H. Vink, Eur. Polym. J. 7, 1411 (1971).
  27. F. Horkay, P. J. Basser, A. -M. Hecht, and E. Geissler, Macromolecules 33, 8329 (2000).
  28. Q. Yan and J. J. de Pablo, Phys. Rev. Lett. 91, 018301 (2003).
  29. S. Schneider and P. Linse, Eur. Phys. J. E 8, 457 (2002).
  30. S. Schneider and P. Linse, J. Phys. Chem. B 107, 8030 (2003).
  31. S. Schneider and P. Linse, Macromolecules 37, 3850 (2004).
  32. S. Edgecombe, S. Schneider, and P. Linse, Macromolecules 37, 10089 (2004).
  33. B. A. Mann, R. Everaers, C. Holm, and K. Kremer, Europhys. Lett. 67, 786 (2004).
  34. B. A. Mann, C. Holm, and K. Kremer, J. Chem. Phys. 122, 154903 (2005).
  35. D. Chandler and J. D. Weeks, Phys. Rev. Lett. 25, 149 (1970).
  36. J. D. Weeks, D. Chandler, and H. C. Andersen, J. Chem. Phys. 54, 5237 (1971).
  37. H. C. Andersen, J. D. Weeks, and D. Chandler, Phys. Rev. A 4, 1597 (1971).
  38. M. J. Stevens and K. Kremer, J. Chem. Phys. 103, 1669 (1995).
  39. U. Micka, C. Holm, and K. Kremer, Langmuir 15, 4033 (1999).
  40. R. B. Bird, C. F. Curtiss, R. C. Armstrong, and O. Hassager, Dynamics of Polymeric Liquids: Kinetic Theory, 2nd ed. (Wiley, New York, 1987), Vol. 2.
  41. H. R. Warner, Jr., Ind. Eng. Chem. Fundam. 11, 379 (1972).
  42. U. Essmann, L. Perera, M. L. Berkowitz, T. A. Darden, H. Lee, and L. G. Pedersen, J. Chem. Phys. 103, 8577 (1995).
  43. G. J. Martyna, M. L. Klein, and M. E. Tuckerman, J. Chem. Phys. 97, 2635 (1992).
  44. A. Sehgal and T. A. P. Seery, Macromolecules 31, 7340 (1998).
  45. A. Sehgal and T. A. P. Seery, Macromolecules 36, 10056 (2003).
  46. D. Reith, H. Meyer, and F. Müller-Plathe, Macromolecules 34, 2335 (2001).
  47. K. Nörtemann, J. Hilland, and U. Kaatze, J. Phys. Chem. A 101, 6864 (1997).
  48. B. Jayaram, S. Swaminathan, D. L. Beveridge, K. Sharp, and B. Honig, Macromolecules 23, 3156 (1990).
  49. R. G. Winkler, M. Gold, and P. Reineker, Phys. Rev. Lett. 80, 3731 (1998).
  50. J. C. Chu and C. H. Mak, J. Chem. Phys. 110, 2669 (1999).
  51. P. J. Lenart, A. Jusufi, and A. Z. Panagiotopoulos, J. Chem. Phys. 126, 044509 (2007).
  52. Q. Yan and J. J. de Pablo, J. Chem. Phys. 114, 1727 (2001).
  53. Q. Yan and J. J. de Pablo, Phys. Rev. Lett. 86, 2054 (2001).
  54. Q. Yan and J. J. de Pablo, J. Chem. Phys. 116, 2967 (2002).
  55. Q. Yan and J. J. de Pablo, Phys. Rev. Lett. 88, 095504 (2002).
  56. A. Z. Panagiotopoulos and M. E. Fisher, Phys. Rev. Lett. 88, 045701 (2002).
  57. M. Rubinstein and R. H. Colby, Polymer Physics, 1st ed. (Oxford University Press, Oxford, UK, 2003).

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