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Composite Structure of Liquid Crystal/Polymer Nanotubes Revealed by High-Angle Annular Dark-Field Scanning Transmission Electron Microscopy

Published online by Cambridge University Press:  28 September 2007

Andreas K. Schaper
Affiliation:
Material Sciences Center, Philipps University, Hans-Meerwein-Str., 35032 Marburg, Germany
Hiroki Kurata
Affiliation:
Institute for Chemical Research, Kyoto University, Uji, Kyoto-fu 611-0011, Japan
Taiyo Yoshioka
Affiliation:
Institute for Chemical Research, Kyoto University, Uji, Kyoto-fu 611-0011, Japan
Masaki Tsuji
Affiliation:
Institute for Chemical Research, Kyoto University, Uji, Kyoto-fu 611-0011, Japan
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Abstract

We have applied high-angle annular dark-field microscopy to the characterization of the structure of template-grown nanotubes composed of a polymer and a discotic liquid crystalline material. Selective staining of the liquid crystal phase with ruthenium tetroxide was used to develop adequate Z-contrast that allows us to distinguish between the two phases. At appropriate staining conditions, we could clearly visualize, in the annular dark-field mode, a 5–15-nm thin liquid crystalline layer precipitated on the inner surface of the polymer tubes. Cryo-electron diffraction has shown high alignment of the discotic columns within the layer parallel to the tube axis. However, although the polymer/liquid crystal phase separation is almost complete, the wetting behavior of the polymer in relation to the template appears to be sensitively influenced by kinetic factors.

Type
MATERIALS APPLICATIONS
Copyright
© 2007 Microscopy Society of America

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References

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