Hostname: page-component-7b7567c8c-2n9c9 Total loading time: 0 Render date: 2026-11-15T01:48:23.061Z Has data issue: false hasContentIssue false
  • English
  • Français

Fast Dynamics in Glass-Forming Polymers Revisited

Published online by Cambridge University Press:  10 February 2011

J. Colmenero,
A. Arbe,
C. Mijangos and
H. Reinecke
J. Colmenero
Affiliation:
Departamento de Física de Materiales, Facultad de Química, Apdo. 1072, 20080 San Sebastián, Spain, wapcolej@sq.ehu.es
A. Arbe
Affiliation:
Departamento de Física de Materiales, Facultad de Química, Apdo. 1072, 20080 San Sebastián, Spain, wapcolej@sq.ehu.es
C. Mijangos
Affiliation:
CSIC, Instituto de Ciencia y Tecnología de Polímeros, Juan de la Cierva 3, 28006 Madrid, Spain
H. Reinecke
Affiliation:
CSIC, Instituto de Ciencia y Tecnología de Polímeros, Juan de la Cierva 3, 28006 Madrid, Spain
Get access

Abstract

The so called “fast-dynamics” of glass-forming systems as observed by time of flight (TOF) neutron scattering techniques is revisited. TOF-results corresponding to several glass-forming polymers with different chemical microstructure and glass-transition temperature are presented together with the theoretical framework proposed by us to interpret these results. The main conclusion is that the TOF-data can be explained in terms of quasiharmonic vibrations and the particular short time behavior of the segmental dynamics. The segmental dynamics display in the very short time range (t ≈ 2 ps) a crossover from a simple exponential behavior towards a non-exponential regime. The first exponential decay, which is controlled by C-C rotational barriers, can be understood as a trace of the behavior of the system in absence of the effects (correlations, cooperativity, memory effects…) which characterize the dense supercooled liquid like state against the normal liquid state. The non-exponential regime at t > 2 ps corresponds to what is usually understood as α and β relaxations. Some implications of these results are also discussed.

Information

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 455: Symposium T – Glasses and Glass Formers–Current Issues , 1996, 17
Copyright
Copyright © Materials Research Society 1997

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

REFERENCES

1. See for example Götze, W. in Liquids, Freezing and the Glass Transition, edited by Hansen, J. P., Levesque, D., and Zinn-Justin, J. (North-Holland, Amsterdam 1991), p. 287.Google Scholar
2. Johari, G. P. and Goldstein, M., J. Chem. Phys. 53, 2372 (1970).Google Scholar
3. See, as an example, McCrum, N. G., Read, B. E. and Williams, G. in Anelastic and Dielectric Effects in Plymer Solids, (Wiley, London, 1967).Google Scholar
4. Arbe, A., Buchenau, U., Willner, L., Richter, D., Farago, B. and Colmenero, J., Phys. Rev. Lett. 76, 1872(1996).Google Scholar
5. Mezei, F., Knaak, W. and Farago, B., Phys. Rev. Lett. 58, 571 (1987).Google Scholar
6. Richter, D., Frick, B. and Farago, B., Phys. Rev. Lett. 61, 2465 (1988).Google Scholar
7. Fujara, F. and Petry, W., Europhys. Lett. 4, 921 (1987).Google Scholar
8. Buchenau, U., Schönfeld, C., Richter, D., Kanaya, T., Kaji, K. and Wehrman, R., Phys. Rev. Lett. 73, 17(1994).Google Scholar
9. Sokolov, A. P., Kisliuk, A., Quitmann, D., Kudlik, A. and Rössler, E., J. Non-Cryst. Solids 172–174, 138(1994).Google Scholar
10. Ngai, K. L., Roland, C. M. and Greaves, G. N., J. Non-Cryst. Solids 182, 172 (1995).Google Scholar
11. Colmenero, J., Arbe, A. and Alegria, A., Phys. Rev. Lett. 71, 2603 (1993).Google Scholar
12. Zorn, R., Arbe, A., Colmenero, J., Frick, B., Richter, D. and Buchenau, U., Phys. Rev. E 52, 781 (1995).Google Scholar
13. Colmenero, J., Arbe, A., Coddens, G., Frick, B., Mijangos, C. and Reinecke, H., Phys. Rev. Lett. 78, 1928(1997)Google Scholar
14. Colmenero, J. and Arbe, A., Macromol. Symp. (accepted for publication).Google Scholar
15. The fragility D is defined by Angeli [see for example, Angeli, C. A., J. Non-Cryst. Solids 131–133, 13 (1991)] as an exponent in the Vogel-Fulcher expression for the viscosity η = ηo exp [DTo / (T-To) To, where To represents the Vogel temperature. A glass former is called fragile if the viscosity diverges rapidly as T varies from T0 in contrast to strong systems, which show simple activation behavior.Google Scholar
16. Glauber, R. J., J. Math. Phys. 4, 294 (1963).Google Scholar
17. See, e. g., Jäkle, J. in Disordered Effects in Relaxation Processes, edited by Richert, R. and Blumen, A. (Springer-Verlag, Berlin 1994), p. 233, and references therein.Google Scholar
18. Shore, J. E. and Zwanzig, R., J. Chem. Phys. 63, 5445 (1975).Google Scholar
19. See as an updated review, Bahar, Y., Erman, B. and Monnerie, L. in Advances in Polymer Science 116, edited by Monnerie, L. and Suter, U. W. (Springer-Verlag, Berlin 1994), p. 143.Google Scholar
20. Lemke, N. and Campbell, Y. A., Physica A 230, 554 (1996).Google Scholar
21. Javier Brey, J. and Prados, A., Phys. Rev. E 53, 458 (1996).Google Scholar
22. Ngai, K. L., Comments Solid State Phys. 9, 128 (1979); for a recent application of this model see, e. g.,Google Scholar
Ngai, K. L. and Rizos, A. K., Phys. Rev. Lett. 76, 1296 (1996).Google Scholar
23. Tsang, Kwork Yeung and Ngai, K. L., Phys. Rev. E 54, R3067 (1996).Google Scholar
24. See as a recent review: Pusey, P. N. in Liquids, Freezing and the Glass Transition, edited by Hansen, J. P., Levesque, D. and Zinn-Justin, J. (North-Holland, Amsterdam 1991), p. 762.Google Scholar
25. See for example: Springer, T. in Quasielastic Neutron Scattering for the Investigation of Diffusive Motions in Solids and Liquids (Springer-Verlag, Berlin 1972).Google Scholar
26. Hendricks, J. et al., to be published.Google Scholar
27. deGennes, P. G., Physica 25, 128 (1959).Google Scholar
28. Arbe, A., Richter, D., Colmenero, J. and Farago, B., Phys. Rev. E 54, 3853 (1996).Google Scholar
29. Meyer, A., Wuttke, J., Petry, W., Peker, A., Bormann, R., Coddens, G., Kranich, L., Randi, O. G. and Schober, H., Phys. Rev. B 53, 12107 (1996).Google Scholar