Synthesis and Thermal Properties of Thermotropic Liquid-Crystalline Para-type Copolyurethane

Jong-Back Lee; Dae-Woong Choi; Dong-Jin Lee

Journal of Industrial and Engineering Chemistry, Vol.3, No.4, 277-281, December, 1997

Jong-Back Lee, Dae-Woong Choi, and Dong-Jin Lee¹

Department of Chemical Engineering, Dongeui University, Pusan 614-714, Korea
¹Institute of Industrial Science, University of Tokyo, Tokyo 106, Japan

Thermotropic liquid-crystalline copolyurethanes were synthesized by the polyaddition reaction of para-type 2,5-tolylene diisocyanate (2,5-TDI) with 4,4'-bis(ω-hydroxyalkoxy)biphenyls (PUmnT; m and n : carbon number in alkoxy moiety). All PU68Ts and PU611Ts as well as individual copolyurethanes were monotropic liquid crystals showing liquid crystallinity on the cooling state under shear. For example, PU611T(50/50) with [η]=0.77 dL/g exhibited an anisotropic phase from 157 to 137℃. Thermal behavior, was investigated by using differential scanning calorimetry (DSC), polarizing microscopy, X-ray diffraction, and thermogravimetric analysis.

[References]

Hager SL, Rury TBM, Gerkin RM, Gritchfield in Urethane Chemistry and Applications, K.N. Edwards, Ed., ACS, Washington, D.C., 172, 149 (1981)
Edwards KN, Urethane Chemistry and Applications, ACS, Washington, D.C., 172, 33 (1981)
Pearson PG, "In Specialty Polymers," R.W. Dyson, Ed; Blackie London, p. 150 (1987)
Tanaka M, Nakaya T, Makromol. Chem., 187, 2345 (1986)
Stenhouse PJ, Valles EM, Kantor SW, MacKnight WJ, Macromolecules, 22, 1467 (1989)
Lee JB, Kato T, Yoshkda T, Uryu T, Macromolecules, 26, 4989 (1993)
Iimura K, Koide N, Tanabe H, Takeda M, Makromol. Chem., 182, 2569 (1981)
Mormann W, Brahm M, Macromol. Chem. Phys., 196, 529 (1995)
Pollack SK, Shen DY, Hsu SL, Wang Q, Stidham HD, Macromolecules, 22, 551 (1989)
Smyth G, Valles EM, Pollack SK, Grebowicz J, Stenhouse PJ, Hsu SL, MacKnight WJ, Macromolecules, 23, 3389 (1990)
Mormann W, Brahm M, Makromol. Chem., 190, 631 (1989)
Lee JB, Kato T, Ujiie S, Iimura K, Uryu T, Macromolecules, 28(7), 2165 (1995)
Lee JB, Kato T, Uryu T, Polym. J., 27, 664 (1995)
Lee JB, Choi DW, J. Korean Ind. Eng. Chem., 8(2), 339 (1997)
Papadimitrakopoulos F, Hsu SL, MacKnight WJ, Macromolecules, 25, 4671 (1992)

[1] Hager SL, Rury TBM, Gerkin RM, Gritchfield in Urethane Chemistry and Applications, K.N. Edwards, Ed., ACS, Washington, D.C., 172, 149 (1981)

[2] Edwards KN, Urethane Chemistry and Applications, ACS, Washington, D.C., 172, 33 (1981)

[3] Pearson PG, "In Specialty Polymers," R.W. Dyson, Ed; Blackie London, p. 150 (1987)

[4] Tanaka M, Nakaya T, Makromol. Chem., 187, 2345 (1986)

[5] Stenhouse PJ, Valles EM, Kantor SW, MacKnight WJ, Macromolecules, 22, 1467 (1989)

[6] Lee JB, Kato T, Yoshkda T, Uryu T, Macromolecules, 26, 4989 (1993)

[7] Iimura K, Koide N, Tanabe H, Takeda M, Makromol. Chem., 182, 2569 (1981)

[8] Mormann W, Brahm M, Macromol. Chem. Phys., 196, 529 (1995)

[9] Pollack SK, Shen DY, Hsu SL, Wang Q, Stidham HD, Macromolecules, 22, 551 (1989)

[10] Smyth G, Valles EM, Pollack SK, Grebowicz J, Stenhouse PJ, Hsu SL, MacKnight WJ, Macromolecules, 23, 3389 (1990)

[11] Mormann W, Brahm M, Makromol. Chem., 190, 631 (1989)

[12] Lee JB, Kato T, Ujiie S, Iimura K, Uryu T, Macromolecules, 28(7), 2165 (1995)

[13] Lee JB, Kato T, Uryu T, Polym. J., 27, 664 (1995)

[14] Lee JB, Choi DW, J. Korean Ind. Eng. Chem., 8(2), 339 (1997)

[15] Papadimitrakopoulos F, Hsu SL, MacKnight WJ, Macromolecules, 25, 4671 (1992)