Hostname: page-component-7bb8b95d7b-pwrkn Total loading time: 0 Render date: 2024-09-26T05:34:52.151Z Has data issue: false hasContentIssue false
  • English
  • Français

Poly(methyl phenyl siloxane) in Random Nanoporous Glasses: Molecular Dynamics and Structure

Published online by Cambridge University Press:  01 February 2011

Andreas. Schönhals ,
Harald. Goering ,
Christoph Schick ,
Bernhard. Frick  and
Reiner Zorn
Andreas. Schönhals
Affiliation:
Federal Institute of Materials Research and Testing, Unter den Eichen 87, D-12205 Berlin, Germany
Harald. Goering
Affiliation:
Federal Institute of Materials Research and Testing, Unter den Eichen 87, D-12205 Berlin, Germany
Christoph Schick
Affiliation:
University of Rostock, Department of Physics, Universitätsplatz 3, D-18051 Rostock, Germany
Bernhard. Frick
Affiliation:
Institute Max von Laue - Paul Langevin 6, rue Jules Horowitz B.P. 156, F-38042 Grenoble Cedex 9, France
Reiner Zorn
Affiliation:
Institute for Solid State Research, D-52425 Jülich, Germany
Get access

Abstract

The effect of a nanometer confinement on the molecular dynamics of poly(methyl phenyl siloxane) (PMPS) was studied by dielectric spectroscopy (DS), temperature modulated DSC (TMDSC) and neutron scattering (NS). DS and TMDSC experiments show that for PMPS in 7.5 nm pores the molecular dynamics is faster than in the bulk which originates from an inherent length scale of the underlying molecular motions. At a pore size of 5 nm the temperature dependence of the relaxation times changes from a Vogel / Fulcher / Tammann like behavior to an Arrhenius one. At the same pore size Δcp vanishes. These results give strong evidence that the glass transition has to be characterized by an inherent length scale of the relevant molecular motions. Quasielastic neutron scattering experiments reveal a strong change even in the microscopic dynamic.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 790: Symposium P – Dynamics in Small Confining Systems–2003 , 2003 , P9.3
Copyright
Copyright © Materials Research Society 2004

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.)

References

REFERENCES

1. Proceedings of the International Workshop on Dynamics in Confinement ed Frick, B., Zorn, R. and Büttner, H, J Phys IV 10, (2000).Google Scholar
2. Proceedings of the International Workshop on Dynamics in Confinement ed Frick, B., Zorn, R. and Koza, M., Eur. Phys. E 12 (2003).Google Scholar
3. Dynamics in Small Confining Systems IV ed. Drake, J.M., Grest, G.S., Klafter, J. and Kopelman, R. Mat. Res. Soc. Symp. Proc. 543 (1998).Google Scholar
4. Kremer, F., Huwe, A., Schönhals, A. and Różański, A.S. “Molecular Dynamics in Confining Space”, Broadband Dielectric Spectroscopy, ed. Kremer, F. and Schönhals, A. (Springer, 2002) p 171.Google Scholar
5. Anderson, P. W., Science 267, 1615 (1995);Google Scholar
Angel, C. A., Science 267, 1924 (1995);Google Scholar
Debenedetti, P.G., and Stillinger, F.H., Nature 410, 259 (2000).Google Scholar
6. Adam, G. and Gibbs, J. H., J. Chem. Phys. 43, 139 (1965);Google Scholar
Kivelson, D., Kivelson, S. A., Zhao, X., Nussinov, Z. and Tarjus, G., Physica A 219, 27 (1995).Google Scholar
7. Donth, E., The Glass Transition (Springer Verlag Berlin 2001)Google Scholar
8. Sillescu, H. J. Non-Cryst. Solids 243, 81 (1999)Google Scholar
9. Ediger, M. D., Ann. Rev. Phys. Chem. 51, 99 (2000)Google Scholar
10. Arndt, M., Stannarius, R., Groothues, H., Hempel, E., and Kremer, F., Phys Rev Lett 79, 2077 (1997).Google Scholar
11. Huwe, A., Kremer, F., Behrens, P., and Schwieger, W., Phys Rev Lett 82, 2338 (1999).Google Scholar
12. Morineau, D., Xia, Y., and Alba-Simionesco, Ch., J. Chem. Phys. 117, 8966 (2002).Google Scholar
13 Schönhals, A., Goering, H., and Schick, Ch., J. Non-Cryst. Solids 305, 140 (2002)Google Scholar
14 Schönhals, A., Goering, H., and Schick, Ch., Phys. Rev. Lett. (submitted)Google Scholar
15 Schönhals, A., Goering, H., Schick, Ch., Zorn, R. and Frick, B., Eur. Phys. E 12 (2003) in pressGoogle Scholar
16. Kremer, F. and Sch, A.önhals “Broadband Dielectric Measurement Techniques”, Broadband Dielectric Spectroscopy, ed. Kremer, F. and Schönhals, A. (Springer, 2002) p 35.Google Scholar
17. Kremer, F. and Schönhals, A. “Analysis of Dielectric Spectra”, Broadband Dielectric Spectroscopy, ed. Kremer, F. and Schönhals, A. (Springer, 2002) p 59.Google Scholar
18. Schick, Ch., Temperature “Modulated Differential Scanning Calorimetry (TMDSC) -Basics and Applications to Polymers”, Handbook of Thermal Analysis and Calorimetry, Vol. 3 ed. Cheng, S. (Elsevier Amsterdam, 2002) p 713.Google Scholar
19. Vogel, H., Phys. Z. 22, 645 (1921);Google Scholar
Fulcher, G.S., J. Amer. Ceram. Soc. 8, 339 (1925);Google Scholar
Tammann, G., Hesse, W., Z. Anorg. Allg. Chem. 156, 245 (1926).Google Scholar
20. This is not in contradiction with the observed molecular mobility by DS. An Arrhenius-like temperature dependence indicates localized molecular motions which cannot be detected by DCSGoogle Scholar
21. Schönhals A, Zorn R, Frick B in preparationGoogle Scholar