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Neutron Reflectivity Measurements of Molecular Weight Effects on Polymer Mobility near the Polymer/Solid Interface

Published online by Cambridge University Press:  01 February 2011

Eric K. Lin ,
Darrin J. Pochan ,
Wen-li Wu  and
Sushil K. Satija
Eric K. Lin
Affiliation:
Polymers Division, Materials Science and Engineering Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Stop 8541, Gaithersburg, MD 20899–8541 USA
Darrin J. Pochan*
Affiliation:
Polymers Division, Materials Science and Engineering Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Stop 8541, Gaithersburg, MD 20899–8541 USA
Wen-li Wu
Affiliation:
Polymers Division, Materials Science and Engineering Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Stop 8541, Gaithersburg, MD 20899–8541 USA
Sushil K. Satija
Affiliation:
Center for Neutron Research, Materials Science and Engineering Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Stop 8541, Gaithersburg, MD 20899–8541 USA
*
* Department of Materials Science and Engineering, University of Delaware Newark, DE 19716
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Abstract

Neutron reflectometry is used to measure the rate of interdiffusion between bilayer samples of deuterated and hydrogenated poly(methyl methacrylate) (PMMA) films with the polymerpolymer interface near the native oxide surface of a silicon wafer. In this work, the effects of a favorable substrate interaction and the molecular weight of each polymer layer are determined. Both the film thickness and the molecular weight of the lower d-PMMA layer are kept constant with a thickness of approximately one radii of gyration (Rg) of the polymer and the molecular weight of the upper hydrogenated layer is varied. Earlier experiments show that the mobility of the polymer chains within Rg of the substrate is much lower than that of the bulk, suggesting that the mobility of surface-pinned polymers controls the interdiffusion rate. In this study, we find that the rate of interdiffusion is strongly dependent upon the molecular weight of the top layer.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 629: Symposium FF – Interfaces, Adhesion and Processing in Polymer Systems , 2000 , FF2.1
Copyright
Copyright © Materials Research Society 2000

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References

REFERENCES

1. Orts, W. J., van Zanten, J. H., Wu, W. L., and Satija, S. K., Phys. Rev. Lett., 71, 867 (1993).Google Scholar
2. Wallace, W. E., van Zanten, J. H., and Wu, W. L., Phys. Rev. E., 52, R3329 (1996).Google Scholar
3. Forrest, J. A., Dalnoki-Veress, K., and Dutcher, J. R., Phys. Rev. E, 56, 5705 (1997).Google Scholar
4. Keddie, J. L., Jones, R. A. L., and R. A., Cory, Faraday Discuss., 98, 219 (1994).Google Scholar
5. van Alsten, J. G., Sauer, B. B., and Walsh, D. J., Macromolecules, 25, 4046 (1992).Google Scholar
6. Hall, D. B. and Torkelson, J. M., Macromolecules, 31, 8817 (1998).Google Scholar
7. Zheng, X., Sauer, B. B., van Alsten, J. G., Schwartz, S. A., Rafailovich, M. H., Sokolov, J., and Rubinstein, M., Phys. Rev. Lett., 74, 407 (1995).Google Scholar
8. Zheng, X., Rafailovich, M. H., Sokolov, J., Strzhemechny, Y., Schwatz, S. A., Sauer, B. B., and Rubinstein, M., Phys. Rev. Lett., 79, 241 (1997).Google Scholar
9. Lin, E. K., Wu., W. L., and Satija, S. K., Macromolecules, 30, 7224 (1997).Google Scholar
10. Lin, E. K., Kolb, R., Wu, W. L., and Satija, S. K., Macromolecules, 32, 3753 (1999).Google Scholar
11. Ankner, J. F. and Majkrzak, C. J. in Neutron Optical Devices (SPIE Proceedings 1738; Bellingham, WA, 1992) p. 260.Google Scholar
12. According to ISO 31–8, the term “molecular weight” has been replaced by “relative molecular mass,” symbol Mr. Thus, if this nomenclature and notation were to be followed in this publication, one would write Mr,n instead of the historically conventional Mn for the number average molecular weight, with similar changes for Mw, Mz, and Mv, and it would be called the “number average relative molecular mass.” The conventional notation, rather than the ISO notation, has been employed for this publication.Google Scholar
13. The data throughout the manuscript and in the figures are presented along with the standard uncertainty (±) involved in the measurement.Google Scholar