Convenient synthesis of a discotic side group liquid crystal polymer

Abstract

The synthesis of a discotic side group liquid crystal polymer based on poly(methyl methacrylate) is reported. This involves the oxidative coupling of 3,3′,4,4′-tetrakis(hexyloxy)biphenyl with 1-hexyloxy-2-methoxybenzene to yield the unsymmetrical triphenylene nucleus, 2-methoxy-3,6,7,10,11-pentakis(hexyloxy)triphenylene. Subsequent demethylation followed by reactions first with 1,11-dibromoundecane and then with the potassium salt of methacrylic acid yielded the polymerisable monomer, 11-[3,6,7,10,11-pentakis(hexyloxy)-2-oxytriphenylene]undecyl methacrylate. This was polymerised in benzene using azoisobutyronitrile as the initiator. The thermal properties of the resulting polymer are described.

References

1. C. T. Imrie, Polymeric Materials Encyclopedia, ed. J. C. Salamone, CRC Press, Boca Raton, 1996, vol. 5, p. 3770.
2. V. Percec and C. Pugh, Side Chain Liquid Crystal Polymers, ed. C. B. McArdle, Blackie and Sons, Glasgow, 1989, ch. 3.
3. V. Percec and D. Tomazos, Comprehensive Polymer Science, First Suppl., ed. S. L. Aggarwal and S. Russo, Pergamon Press, Oxford, 1992, ch. 14.
4. C. Bowry and P. Bonnett, Opt. Comput. Proc., 1991, 1, 13.
5. K. M. Blackwood, Science, 1996, 273, 909.
6. T. Ikeda and O. Tsutsumi, Science, 1995, 268, 1873.
7. W. Kreuder and H. Ringsdorf, Makromol. Chem., Rapid Commun., 1983, 4, 807.
8. W. Kranig, B. Hüser, H. W. Spiess, W. Kreuder, H. Ringsdorf and H. Zimmermann, Adv. Mater., 1990, 2, 36.
9. M. Werth and H. W. Spiess, Makromol. Chem., Rapid Commun., 1993, 14, 329.
10. C. D. Favre-Nicolin and J. Lub, Macromolecules, 1996, 29, 6143.
11. N. Boden, R. C. Borner, R. J. Bushby, A. N. Cammidge and M. V. Jesudason, Liq. Cryst., 1993, 15, 851.
12. N. Boden, R. J. Bushby and A. N. Cammidge, J. Chem. Soc., Chem. Commun., 1994, 465.
13. N. Boden, R. J. Bushby and A. N. Cammidge, J. Am. Chem. Soc., 1995, 117, 924.
14. N. Boden, R. J. Bushby, A. N. Cammidge and G. Headdock, J. Mater. Chem., 1995, 5, 2275.
15. J. W. Goodby, M. Hird, K. J. Toyne and T. Watson, J. Chem. Soc., Chem. Commun., 1994, 1701.
16. G. W. Gray, M. Hird, D. Lacey and K. J. Toyne, J. Chem. Soc. Perkin Trans. 2, 1989, 2041.
17. J. F. W. McOmie, M. L. Watts and D. E. West, Tetrahedron, 1968, 24, 2289.
18. R. E. Ireland and D. M. Walba, Org. Synth., 1977, 56, 44.
19. G. S. Attard, S. Garnett, C. G. Hickman, C. T. Imrie and L. Taylor, Liq. Cryst., 1990, 7, 495.
20. A. A. Craig and C. T. Imrie, J. Mater. Chem., 1994, 4, 1705.
21. C. T. Imrie, F. E. Karasz and G. S. Attard, J. Macromol. Sci.-Pure Appl. Chem., 1994, A31, 1221.
22. Z. Komiya, C. Pugh and R. R. Schrock, Macromolecules, 1992, 25, 3609.
23. N. Boden, R. J. Bushby, A. N. Cammidge and P. S. Martin, J. Mater. Chem., 1995, 5, 1857.
24. C. T. Imrie, F. E. Karasz and G. S. Attard, Macromolecules, 1993, 26, 545.
25. M. Werth, S. U. Vallerien and H. W. Spiess, Liq. Cryst., 1991, 10, 759.
26. C. T. Imrie, F. E. Karasz and G. S. Attard, Macromolecules, 1993, 26, 3803.