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Aromatic liquid-crystalline polyesters comprising a 2,5-thiophene unit synthesized and studied by the thin-film polymerization method

Published online by Cambridge University Press:  31 January 2011

Jingmei Xu ,
Yan Wang ,
Tai-Shung Chung  and
Suat Hong Goh
Jingmei Xu
Affiliation:
Institute of Materials Research and Engineering, 3 Research Link, Singapore 117602
Yan Wang
Affiliation:
Institute of Materials Research and Engineering, 3 Research Link, Singapore 117602, and Department of Chemistry, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260
Tai-Shung Chung*
Affiliation:
Department of Chemical and Environmental Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260
Suat Hong Goh
Affiliation:
Department of Chemistry, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260
*
a)Address all correspondence to this author. e-mail: chencts@nus.edu.sg
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Abstract

A series of novel liquid-crystalline polymer (LCP) systems, including a heterocyclic 2,5-thiophene unit, were synthesized and studied using a modified thin-film polymerization method as part of a continuing investigation of molecular structural effects on liquid crystallinity. The monomers used in the reaction included p-acetoxybenzoic acid (ABA)/2,6-acetoxynaphtholic acid (ANA), 4,4′-biphenol (BP)/4,4′-diacetoxybiphenyl (DABP)/p-acetoxyacetanilide (AAA), and 2,5-thiophenedicarboxylic acid (TDA). Polarizing light microscopy and Fourier transform infrared spectra were used to study, in situ record the evolution of morphological change in the thin-film polymerization process, and confirm the occurrence of polymerization. Experimental results indicated that monomer structure and composition as well as temperature influence the formation of the liquid crystalline (LC) phase greatly and revealed that 2,5-thiophene structure is a viable mesogenic core unit. It is more effective than isophthalic acid (IA) in assisting in the LC formation as polymers containing TDA have a better developed LC phase and lower critical ABA content than those with IA. Stripe texture was observed in the ANA/DABP/TDA system, possibly due to the structural characteristics and matching of the monomers. The decrease of isotropic round areas in the LC phase and the annihilation between two pairs of defects with reaction time were also studied.

Type
Articles
Information
Journal of Materials Research , Volume 18 , Issue 7 , July 2003 , pp. 1509 - 1521
Copyright
Copyright © Materials Research Society 2003

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References

REFERENCES

1.Chung, T.S., Calundann, G.W., and East, A.J., Encyclopedia of Engineering Materials (Marcel Dekker, New York, 1989), Vol. 2, p. 625.Google Scholar
2.Jackson, W.J., Mol. Cryst. Liq. Cryst. 169, 23 (1989).Google Scholar
3.Weiss, R.A., and Ober, C.K., in Liquid Crystalline Polymers, edited by Weiss, R.A. and Ober, C.K. (American Chemical Society, Washington, DC, 1990).CrossRefGoogle Scholar
4.Ciferri, A., in Liquid Crystallinity in Polymers: Principles and Fundamental Properties, edited by Ciferri, A. (VCH Publishers, New York, 1991).Google Scholar
5.Collyer, A.A., in Liquid Crystal Polymers: From Structures to Applications, edited by Collyer, A.A. (Elsevier Applied Science, London, U.K., 1992).Google Scholar
6.Economy, J. and Goranov, K., Adv. Polym. Sci. 117, 221 (1994).CrossRefGoogle Scholar
7.Jin, J.I. and Kang, C.S., Prog. Polym. Sci. 22, 937 (1997).CrossRefGoogle Scholar
8.Chung, T.S., in Advances in Thermotropic Liquid Crystal Polymers (CRC Press, Boca Raton, FL, 2001).Google Scholar
9.Chung, T.S., Cheng, S.X., and Jaffe, M., in Thermotropic Main-Chain Liquid Crystalline Polymers, Encyclopedia of Polymer Science and Technology, edited by Kroschwitz, J. (Wiley, New York, 2001), online.Google Scholar
10.Jaffe, M. and Chung, T.S., in Handbook of Thermoplastic Polyesters, Main-Chain Thermotropic Polyesters, edited by Fakirov, S. (Wiley-VCH, Weinheim, Germany, 2002), p. 659.CrossRefGoogle Scholar
11.Gray, G.W., in Thermotropic Liquid Crystals, edited by Gray, G.W. (Society of Chemical Industry by Wiley, New York, 1987).Google Scholar
12.Gallardo, H.F. and Favarin, I., Liq. Cryst. 13, 115 (1993).Google Scholar
13.Kossmehl, G. and Hoppe, F., Liq. Cryst. 15, 383 (1993).CrossRefGoogle Scholar
14.Tschierske, C. and Joachimi, D., Liq. Cryst. 9, 397 (1991).Google Scholar
15.Melamed, D., Nuckols, C., and Fox, M.A., Tetrahedron Lett. 35, 8329 (1994).Google Scholar
16.Byron, D., Komitov, L., Matharu, A., Mcsherry, I., and Wilson, R., J. Mater. Chem. 6, 1871 (1996).CrossRefGoogle Scholar
17.Kijima, M., Akaji, K., and Shirakawa, H., Synth. Met. 84, 237 (1997).Google Scholar
18.Chen, S.H., Conger, M.B., Mastrangelo, J.C., Kende, A.S., and Kim, D.U., Macromolecules 31, 8051 (1998).CrossRefGoogle Scholar
19.Konstantinova, L.S., Rakitin, O.A., Rees, C.W., Souvorova, L.I., and Rorroba, T., J. Chem. Soc., Perkins Trans. 1 8, 1023 (1999).CrossRefGoogle Scholar
20.Cai, R.B. and Samulski, E.T., Liq. Cryst. 9, 617 (1991).CrossRefGoogle Scholar
21.Stompel, S., Samulski, E.T., Preston, J., Hsiao, B.S., Gardner, K.H., and Shih, H., High Perform. Polym. 9, 229 (1997).Google Scholar
22.Promislow, J.H., Preston, J., and Samulski, E.T., Macromolecules 26, 1793 (1993).CrossRefGoogle Scholar
23.Cai, R.B., Preston, J., and Samulski, E.T., Macromolecules 25, 563 (1992).Google Scholar
24.Kossmehl, G. and Pithart, C., Z. Naturforsch., B 47, 567 (1992).Google Scholar
25.Kossmehl, G. and Hoppe, F.D., Mol. Cryst. Liq. Cryst. A 257, 169 (1994).Google Scholar
26.Kossmehl, G. and Hoppe, F.D., Z. Naturforsch, B 48, 1807 (1993).CrossRefGoogle Scholar
27.Kossmehl, G., Hoppe, F.D., and Hirsch, B., Z. Naturforsch., B 48, 826 (1993).CrossRefGoogle Scholar
28.Hoppe, F. and Kossmehl, G., Liq. Cryst. 21, 255 (1996).Google Scholar
29.Kossmehl, G. and Hirsch, B., Z. Naturforsch., B 50, 1265 (1995).CrossRefGoogle Scholar
30.Kossmehl, G. and Labahn, B., Z. Naturforsch, B 51, 286 (1996).Google Scholar
31.Kossmehl, G. and Hoppe, F.D., Liq. Cryst. 22, 137 (1997).Google Scholar
32.Cheng, S.X., Chung, T.S., and Mullick, S., Chem. Eng. Sci. 54, 663 (1999).Google Scholar
33.Cheng, S.X., T.S Chung, and Mullick, S., J. Polym. Sci., Part B: Polym. Phys. 37, 3084 (1999).Google Scholar
34.Asrar, J., Toriumi, H., Watanabe, J., Krigbaum, W.R., and Ciferri, A., J. Polym. Sci., Part B: Polym. Phys. 21, 1119 (1983).Google Scholar
35.Pham, C., Macomber, R.S., Mark, H.B., and Zimmer, H., J. Org. Chem. 49, 5250 (1984).Google Scholar
36.Chung, T.S. and Cheng, S.X., J. Phys. Chem. B 103, 4923 (1999).Google Scholar
37.Cheng, S.X. and Chung, T.S., J. Polym. Sci., Part B: Polym. Phys. 38, 2221 (2000).3.0.CO;2-O>CrossRefGoogle Scholar
38.Wang, Y., Xu, J.M., Cheng, S.X., Chung, T.S., and Goh, S.H., Liq. Cryst. (unpublished).Google Scholar
39.Calundann, G.W., U.S. Patent 4 067 852 (1978), 4 161 470 (1979), 4 184 996 (1980); A.J. East, L.F. Charbonneau, and G.W. Calundann, U.S. Patent 4 330 457 (1982) (to Hoechst Celanese).Google Scholar
40.Wu, L.H., Wang, Y.C., and Hsu, C.S., Liq. Cryst. 27, 1503 (2000).CrossRefGoogle Scholar
41.Viney, C. and Putnam, W., Polymer 36, 1731 (1995).CrossRefGoogle Scholar
42.Wang, W., Lieser, G., and Wegner, G., Liq. Cryst. 15, 1 (1993).Google Scholar
43.Wang, W., Lieser, G., and Wegner, G., Makromol. Chem. 194, 1289 (1993).Google Scholar
44.Chen, S.X., Cai, L.Y., Wu, Y.Z., Jin, Y.Z., Zhang, S.F., Qin, Z.H., Song, W.H., and Qian, R.Y., Liq. Cryst. 13, 365 (1993).Google Scholar
45.Chen, S.X., Song, W.H., Jin, Y.Z., and Qian, R.Y., Liq. Cryst. 15, 247 (1993).Google Scholar
46.Dimitrowa, K., Hauschilkd, J., Zaschke, H., and Shubert, H., J. Prakt. Chem. 322, 933 (1980).CrossRefGoogle Scholar
47.Semmler, K.J.K., Dingemans, T.J., and Samulski, E.T., Liq. Cryst. 24, 799 (1998).Google Scholar