Thermal Properties of a Liquid-Crystalline Polyurethanes Containing Biphenyl Mesogen

Abstract:

Article Preview

A new type of thermotropic main-chain liquid crystalline polyurethanes containing biphenyl units was synthesized by polyaddition reaction of diisocyanates such as 2,6-tolylene diisocyanate, 2,5-tolylene diisocyanate, 2,4-tolylene diisocyanate, and 1,4-phenylene diisocyanate, with 4,4′-Bis(11-hydroxyundeyloxy)biphenyl (BP11). The structure of the monomer and the corresponding polymers were confirmed FT-IR and 1H NMR spectroscopic methods. BP11 exhibited a smectic type mesophase, however, nematic phase was found for all synthesized liquid crystalline polyurethanes except for 1,4-phenylene diisocyanate/BP11 based polyurethane. For example, polyurethane 2,5-TDI/BP11 exhibited monotropic liquid crystallinity in the temperature ranges from 173 to 156 °C on the cooling stage.

Info:

Periodical:

Key Engineering Materials (Volumes 321-323)

Edited by:

Seung-Seok Lee, Joon Hyun Lee, Ik Keun Park, Sung-Jin Song, Man Yong Choi

Pages:

1385-1388

DOI:

10.4028/www.scientific.net/KEM.321-323.1385

Citation:

J. B. Lee et al., "Thermal Properties of a Liquid-Crystalline Polyurethanes Containing Biphenyl Mesogen", Key Engineering Materials, Vols. 321-323, pp. 1385-1388, 2006

Online since:

October 2006

Export:

Price:

$38.00

[1] P. J. Collings and M. Hird: Introduction to Liquid crystals, Taylor & Francis Ltd, 1997, 30.

[2] J. I. Jin, S. Antoun, C. Ober and R. W. Lenz: Polym. J., Vol. 12 (1980), p.132.

[3] K. Iimura, N. Koide, H. Tanabe and M. Takeda: Makrmol. Chem., Vol. 182 (1981), p.2569.

[4] P. J. Stenhouse, E. M. Valles, S. W. Kantor and W. J. MacKnight: Macromolecules, Vol. 22 (1989), p.1467.

[5] J. B. Lee, T. Kato, S. Ujiie, K. Iimura and T. Uryu: Macromolecules, Vol. 28 (1995), p.2165.

[6] D. J. Lee, J. B. Lee, N. Koide, E. Akiyama and T. Uryu: Macromolecules, Vol. 31 (1998), p.975.

In order to see related information, you need to Login.