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Prolonged Chaotic Oscillations During the Gel/Xerogel Transition in Silicon Tetramethoxide Polymerization as Detected by Pyrene Excimerization.

Published online by Cambridge University Press:  28 February 2011

Vered R. Kaufman  and
David Avnir
Vered R. Kaufman
Affiliation:
Department of Organic Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
David Avnir
Affiliation:
Department of Organic Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
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Abstract

When the polymerization of Si(OCH3)4 is carried out in the presence of surface active agents, prolonged oscillations (over 1000 hrs) at the gel/xerogel transition are observed. The oscillations are of large amplitude, they are slow (several hrs/period), and they exhibit a chaotic behaviour. The probe by which these oscillations are observed is emission from excited state monomeric and excimeric pyrene. It is suggested tentatively that the driving forces for this oscillation are the structural relaxation of the secondary polymeric gel structure and the dispersion of adsorbed pyrene to thermodynamically favored adsorption sites. Relevant models could be those of oscillatory sol/gel phase transitions and of oscillatory polymerization reactions. We are unaware of previous observations of oscillations in sol/gel systems.

Type
Articles
Information
MRS Online Proceedings Library (OPL) , Volume 73: Symposium H – Better Ceramics Through Chemistry II , 1986 , 145
Copyright
Copyright © Materials Research Society 1986

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References

REFERENCES

1. Kai, S. and Müller, S.C., Sci. Form, 1, 9 (1985).Google Scholar
2. Noyes, R.M. and Field, R.J., Ann. Rev. Phys. Chem., 25, 95 (1974).CrossRefGoogle Scholar
3. Noyes, R.M., Ber. Bunesges. Phys. Chem. 84, 295 (1980), and articles in that issue.Google Scholar
4. Pismen, L.M., Chem. Eng. Sci., 35, 1950 (1980).Google Scholar
5. Epstein, I.R., Kustin, K., Kepper, P. De and Orban, M., Sci. Am. 248, 96 (March 1983).CrossRefGoogle Scholar
6. Nicolis, G. and Portnow, J., Chem. Rev. 73, 365 (1973).Google Scholar
7. Haken, H., “Synergetics, an Introduction”, 3rd ed., Springer Verlag, Berlin, 1983.Google Scholar
8. Nicolis, G. and Prigogine, I., “Self Organization in Non-Equilibrium Systems”, Wiley, N.Y. (1977).Google Scholar
9. Hlavacek, V. and Rompay, P. Van, Chem. Eng. Sci., 36, 1587 (1981).Google Scholar
10. E.g., Hudson, J.L., Hart, M. and Marinko, D., J. Chem. Phys. 71, 1601 (1979); C. Vidal, J.C. Roux, S. Bachelart and A. Rossi, Ann. N.Y. Acad. Sci., 357, 377 (1980).Google Scholar
11. “Chaos and Order in Nature”, Haken, H., Ed., Springer Verlag, Berlin, 1984.Google Scholar
12. “Evolution of Order and Chaos”, Haken, H., Ed., Springer Verlag, Berlin, 1982.Google Scholar
13. Kaufman, V.R., Levy, D. and Avnir, D., J. Non Cryst. Solids, 1986, in press.Google Scholar
14. Kaufman, V.R. and Avnir, D., Proc. Int. Conf. Unconventional Solids, Scher, H., Ed., Plenum Press, 1986.Google Scholar
15. Kaufman, V.R. and Avnir, D., Langmuir, submitted, 1986.Google Scholar
16. E.g., Mayo, P. de, Natarajan, L.V. and Ware, W.R., Chem. Phys. Lett., 107, 187 (1984); P. Levitz, H. Van Damme and P. Keravis, J. Phys. Chem., 88, 2228 (1984); D. Oelkrug and M. Radjaipur, Z. Phys. Chem., 123, 163 (1980); K. Chandrasekaran and J.K. Thomas, J. Colloid Interface Sci., 100, 116 (1984).Google Scholar
17. Avnir, D., Busse, R., Ottolenghi, M., Wellner, E. and Zachariasse, K., J. Phys. Chem., 89, 3521 (1985).CrossRefGoogle Scholar
18. Wellner, E., Ottolenghi, M., Avnir, D. and Huppert, D., Langmuir, submitted, 1986.Google Scholar
19. Brinker, C.J. and Scherer, G.W., J. Non-Cryst. Solids, 70, 301 (1985) and references cited therein.CrossRefGoogle Scholar
20. Levy, D. and Avnir, D. in ref. 14; D. Avnir, V.R. Kaufman and R. Reisfeld, J. Non Cryst. Solids, 74, 395 (1985); D. Avnir, D. Levy and R. Reisfeld, J. Phys. Chem., 88, 5956 (1984); D. Levy, R. Reisfeld and D. Avnir, Chem. Phys. Lett., 109, 593 (1984)Google Scholar
21. Farin, D., Volpert, A. and Avnir, D., J. Am. Chem. Soc., 107, 3368, 5319 (1985) and previous publications.Google Scholar
22. Avnir, D., this volume.Google Scholar
23. To be published.Google Scholar
24. Lissent, J.K., “Emulsions and Emulsion Technology”, Dekker, N.Y., 1974.Google Scholar
25. Klonowski, W., J. Mat. Res., submitted, 1985.Google Scholar
26. Brinker, C.J., Roth, E.P., Scherer, G.W. and Tallant, D.R., J. Non-Cryst. Solids, 71, 171 (1985).Google Scholar
27. Hu, C.K., Ann. Rep. Inst. Phys. Acad. Sinica, 14, 7 (1984).Google Scholar
28. Coniglio, A., Stanley, H.E. and Klein, W., Phys.Rev. Lett., 42, 578 (1979).CrossRefGoogle Scholar
29. Klonowski, W., J. Appl. Phys., 58, 2883 (1985).CrossRefGoogle Scholar
30. Pismen, L.M. and Kuchanov, S.I., Vysokomol. Soed. (Polymer Sci. USSR), 13, 689, 2035 (1971)Google Scholar
31. Kiparssides, C., MacGregor, J.F. and Hamielec, A.E., J. Appl. Polym. Sci., 23, 401 (1979).Google Scholar
32. Kirilov, V.A. and Ray, W.H., Chem. Eng. Sci., 33, 1499 (1978); J.W. Hammer, T.A. Akramov and W.H. Ray, Chem. Eng. Sci., 367,1897 (1981); R. Jaisinghani and W.H. Ray, Chem. Eng. Sci., 32, 811 (1977).Google Scholar
33. Hyver, C., J. Chem. Phys. 83, 850 (1985).CrossRefGoogle Scholar
34. Gerrens, H. and Kuchner, K., Br. Polym. J., 2, 18 (1970); G. Ley and H. Gerrens, Macromol. Chem. 175, 563 (1974).CrossRefGoogle Scholar
35. Owen, J.J., Steele, C.T., Parker, P.T. and Carrier, E.W., Ind. Eng. Chem., 39, 110 (1947); B. Jacobi, Angew. Chem., 64, 539 (1952).Google Scholar
36. Knorr, R.S. and O'Driscoll, K.F., J. Appl. Polym. Sci., 14, 2683 (1970).Google Scholar
37. Avnir, D. and Kagan, M., Nature, 307, 717 (1984).Google Scholar