Abstract
Optically pure, helical poly(quinoxaline-2,3-diyl)s (degree of polymerization, n=10–100), prepared by asymmetric living polymerization of 1,2-diisocyano-3,6-dimethyl-4,5-di(propoxymethyl)benzene with an optically pure organopalladium initiator, formed stable monolayers on a water surface. As the polymerization degree increased, more closely packed monolayers were formed, as indicated by surface pressure-area (π-A) isotherms. Up to 54 monolayers were deposited onto the solid support using the Langmuir–Blodgett (LB) technique. Polarized ultraviolet spectra of LB films showed that the helical axis was orientated parallel to the dipping direction. This optical property indicates that polymer molecules are organized anisotropically in LB films.
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Acknowledgements
We thank Professor Shuji Okada and Professor Hachiro Nakanishi, IMRAM, Tohoku University, for the use of an X-ray diffractometer, and Professor Masahiko Yamaguchi, Faculty of Pharmaceutical Science, Tohoku University, for the use of CD spectrophotometer.
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Ito, Y., Miyake, T., Suginome, M. et al. Langmuir–Blodgett films of helical rigid-rod poly(quinoxaline-2,3-diyl)s. Polym J 42, 406–410 (2010). https://doi.org/10.1038/pj.2010.14
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DOI: https://doi.org/10.1038/pj.2010.14
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