Synthesis of Thermotropic Polyurethanes Containing Biphenylnate and Imide Units and their Mesophase Behavior

Abstract:

A series of novel liquid crystal polyurethanes containing biphenylnate and imide units were synthesized through the polyaddition reaction of 4,4′-Bis-(2-hydroxyhexoxy)biphenyl (BP2), 2,4-toluenediisocyanate (2,4-TDI) with N,N′-bis(2-hydroxyhexyl)-dicarboxyimide (BHDI) by altering the molar ratio of BP2 and BHDI. The effects of structure difference molar ratio between BP2 and BHDI on the liquid crystalline behavior and thermal stability were studied. Results showed that all of the polyurethane polymers exhibited thermotropic nematic liquid crystalline textures in the range of 160~190°C. The melting temperatures (Tm) and the thermal stability increased with increasing BHDI content.

• Periodical: Advanced Materials Research (Volumes 197-198)
• Pages: 1332-1336
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.197-198.1332
• Online since: February 2011
• Authors: Zhi Yi Huang, Shao Rong Lu, Zhi You Yang, Dong Guo, Chong Xi Luo
• Keywords: Characterization, Liquid Crystal Polyurethane, Synthesis, Texture

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