Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
권호 표지

Thermotropic Polyurethanes Prepared from Diisocyanates and 4,4'-Bis(3-hydroxypropoxy)Biphenyl Containing Mesogenic Unit

4,4'-Bis(3-hydroxypropoxy)Biphenyl와 Diisocyanate 에 의한 열방성 액정폴리우레탄 합성

  • Lee, Jong Baek (Department of Chemical Engineering, Dongeui University)
  • 이종백 (동의대학교 화학공학과)
  • Received : 2010.04.12
  • Accepted : 2010.06.01
  • Published : 2010.10.31
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, five series of novel polyurethanes was synthesized by the polyaddition reaction of diisocyanates such as 2,6-tolylene diisocyanate(2,6-TDI), 2,5-tolylene diisocyanate(2,5-TDI), 2,4-tolylene diisocyanate(2,4-TDI), and 1,4-phenylene diisocyanate(1,4-PDI), hexamethylene diisocyanate(HDI) with 4,4'-Bis(3-hydroxypropoxy)biphenyl (BP3), 4,4'-bis(3-hydroxypropoxy)biphenyl exhibited a smectic type mesophase. Monotropic mesophase was found for all synthesized liquid crystalline polyurethanes except HDI/BP3. In contrast, 1,4-PDI/BP3 without a methyl substituent in the phenylene unit exhibited no explicit mesomorphic behavior, which was confirmed by DSC and polarizing microscopy experiments. Structures of the compound were identified by FT-IR and $^1H$-NMR spectroscopies. Their phase transition temperatures and thermal stability were also investigated by differential scanning calorimetry(DSC), polarized optical microscopy(POM) and x-ray diffraction analysis.

본 실험은 다섯 종류의 새로운 형태의 액정성 폴리우레탄을 4,4'-Bis(3-hydroxypropoxy)biphenyl (BP3)와 2,6-tolylene diisocyanate(2,6-TDI), 2,5-tolylene diisocyanate(2,5-TDI), 2,4-tolylene diisocyanate(2,4-TDI), 1,4-phenylene diisocyanate(1,4-PDI) 및 hexamethylene diisocyanate(HDI)의 중부가 반응에 의해 합성하였다. 단량체 BP3은 스멕틱상을 형성하였으며 HDI/BP3을 제외한 나머지 폴리우레탄에서는 모두 단방성 액정성을 나타내었다. 그러나 메틸 치환기를 가지고 있지 않는 1,4-PDI/BP3에서는 DSC 및 편광현미경에서도 액정상을 전혀 관찰할 수 없었다. 합성된 화합물의 구조는 FT-IR 및 $^1H$-NMR에 의해 확인하였으며, 그들의 열적 상전이온도 및 안정성들은 DSC, 편광현미경 및 x-선 회절에 의해 조사하였다.

Keywords

References

  1. Collings, P. J., "Liquid crystals, Princeton University Press," pp. 3-23(1990).
  2. Collings, P. J. and Hird, M., "Introduction to Liquid crystals, Taylor & Francis Ltd," pp. 3-23(1997).
  3. Jin, J. I., Antoun, S., Ober, C. and Lenz, R. W., "Thermotropic Liquid Crystalline Polyesters with Rigid or Flexible Spacer Groups," Polym. J., 12, 132(1980).
  4. Uryu, T. and Kato, T., "Solid-State Cross polarization/Magic Angle Spinning $^{13}C$ NMR Study of Thermotropic Aromatic Polyester Containing a Flexible Spacer in The Main Chin," Macromolecules, 21, 378(1988). https://doi.org/10.1021/ma00180a015
  5. Sun, S. J., Cheng, H. P., Chang, T. C. and Chang, C. H., "Studies on The Thermotropic Liquid Crystalline Polycarbonates," Eur. Polym. J. 31, 825(1995). https://doi.org/10.1016/0014-3057(95)00030-5
  6. Lee, H. S., Jung, W. H., Kim, W. N. and Hyun, J. C., "Properties of Blends of Polycarbonate and Thermotropic Liquid Crystalline Polymer," Polym(Korea), 29, 813 (1996).
  7. Penczek, P. K. C., Szczepaniak, F. B. and Rudnik, E., "Synthesis and Properties of Liquid Crystalline Polyurethanes," J. Polym. Sci., Part A: Polym. Chem., 31, 1211(1993). https://doi.org/10.1002/pola.1993.080310517
  8. Kricheldorf, H. R. and Awe, J., "Nematic Polyurethanes derived from 4,4'-Dihydroxybiphenyl and 4,4'-Bipiperidine, Ethylene-4,4'- bipiperidine or Trimethylene-4,4'-bipiperidine," Makromol. Chem., 190, 2579(1989). https://doi.org/10.1002/macp.1989.021901023
  9. Iimura, K. N., Koide, H. and Takeda, M., "Syntheses of Thermotropic Liquid Crystalline Polymers," Makrmol. Chem., 182, 2569 (1981). https://doi.org/10.1002/macp.1981.021821005
  10. Tanaka, M. and Nakaya, T., "Liquid Crystalline Polyurethanes," Makromol. Chem., 187, 2345(1986). https://doi.org/10.1002/macp.1986.021871005
  11. Stenhouse, P. J., Valles, E. M., Kantor, S. W. and MacKnight, W. J., "Thermal and Rheological Properties of a Liquid-Crystalline polyurethane," Macromolecules, 22, 1467(1989). https://doi.org/10.1021/ma00193a077
  12. Lee, J. B., Kato, T., Yoshida, T. and Uryu, T., "Synthesis and Liquid Crystalline Properties of Thermotropic Polyurethanes Prepared from 1,4-Diisocyanates and 4,4'-Bis($\omega$-hydroxyalkoxy)biphenyls," Macromolecules, 26, 4989(1993). https://doi.org/10.1021/ma00071a001
  13. Lee, J. B., Kato, T., Ujiie, S., Iimura, K. and Uryu, T., "Thermotropic Polyurethanes Prepared from 2,5-Tolylene Diisocyanates and 1,4-Bis(-hydroxyalkoxy)benzenes Containing No Mesogenic Unit," Macromolecules, 28, 2165(1995). https://doi.org/10.1021/ma00111a010
  14. Lee, J. B., Kato, T. and Uryu, T., "Synthesis and Thermotropic Properties of polyurethanes Prepared from 2,5-Tolylene Diisocyanate and 2,6-Bis($\omega$-hydroxyalkoxy)naphthalenes," Polymer. J., 27, 664(1995). https://doi.org/10.1295/polymj.27.664
  15. Lee, D. J., Lee, J. B., Koide, N., Akiyama, E. and Uryu, T., "Liquid Crystallinity of Thermotropic Para-Type Home- and Copolyurethanes containing Biphenylene Mesogen and Their Blends," Macromolecules, 31, 975(1998). https://doi.org/10.1021/ma970866y
  16. Lee, J. B. and Song, J. C., "Synthesis and Characterization of Main-Chain Liquid Crystalline Polymers Coining Amide Group," J. Ind. Eng. Chem., 4, 140(1998).
  17. Jeong, H. M., Lee, J. B., Lee, S. Y. and Kim, B. K., "Shape Memory Polyurethane Containing Mesogenic Moiety," J. Materials Sci., 35, 279(2000). https://doi.org/10.1023/A:1004728814128
  18. Lee, J. B., "Thermal Properties of Liquid-Crystalline Polyurethanes Containing Biphenylene Mesogenic Units," J. Ind. Eng. Chem., 6, 338(2000).
  19. Lee, J. B., "The Effect of Substituents on the Liquid Crystalline Behavior of Polyurethanes," J. Korean Ind. Eng. Chem., 12, 649 (2001).
  20. Lee, J. B., Lee, K. H., Kang, B. C. and Lee, D. J., "Synthesis and Characterization of Thermotropic Liquid Crystalline polymerization," Elasto. and Comp. 44(3), 329-335(2009).
  21. Lee, J. B., Kang, B. C., Lee G. C. and Lee, D. J., "Synthesis and Characterization of New Main Chain Liquid Cryatalline Coumarin Compound with Ester Moiety," Elasto. and Comp. 44(4), 416-422(2009).