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High-Resolution Solid-State 13C NMR Study on Effects of Blending on Chain Dynamics in Polystyrene/Poly (Vinyl Methyl Ether) Blends

  • K. Takegoshi
  • Kunio Hikichi
Conference paper

Abstract

To clarify effects of blending on motions of the individual polymer components in the compatible blend polystyrene/poly (vinvl methyl ether) (PS/PVME), temperature dependence of the 13C NMR linewidth for the CH carbon in PVME was studied under magic-angle spinning and proton dipolar-decoupling. The observed temperature dependence above the glass transition temperature was satisfactorily explained by assuming that the tempereature dependence is brought about by the effects of molecular motions as follows: (1) the averaging of the dispersion of the isotropic chemical shifts in the glass state, and (2) the interference of the local anisotropic motion and high-power proton decoupling.

The activation parameters for the motion of PVME in each blend could be described by a single Arrhenius equation. No distribution for the pre-exponential factor nor for the activation energy were discernible. Three main effects of blending on motion are appreciable: with increasing the PS content, (I) the characteristic temperature for the onset of the motion of PVME increases, (II) the activation energy E& decreases, and (III) the anisotropy of the motion increases. These lead us to conclude that microscopically homogeneous mixing is achieved for PS/PVME. This conclusion is in accordance with the DSC results, 1 and the observation of the 9fast spin diffusion in polarization-transfer experiments, 2 and the two-dimensional exchange H NMR in solids. 3

References

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    M. Bank, J. Leffingwell, and C. Thies, Macromolecules 4, 43 (1971).ADSCrossRefGoogle Scholar
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    T.K. Kwei, T. Nishi, and R.F. Roberts, Macromolecules 7, 667 (1974).ADSCrossRefGoogle Scholar
  3. 3).
    P. Caravatti, P. Neuenschwander, and R.R. Ernst, Macromolecules 18, 119 (1985).ADSCrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • K. Takegoshi
    • 1
  • Kunio Hikichi
    • 1
  1. 1.Department of Polymer Science, Faculty of ScienceHokkaido UniversitySapporoJapan

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