Liquid Crystal and Rheological Behavior of 2,6-Bis(benzylidene)cyclohexanone

Abstract

The liquid crystalline compound, 2,6-bis(benzylidene)cyclohexanone was synthesized using benzaldehyde and cyclohexanone as raw material, and tetrabutyl ammonium bromide as phase-transfer catalyst in the solution of sodium hydroxide. The effect of several factors, such as reaction time, reaction temperature, and concentration of sodium hydroxide, has been investigated. The product was characterized by infrared spectra, ¹H NMR and elemental analysis. The physicochemical behavior of the crystalline compound was studied by differential scanning calorimetry, polarizing microscope, and rheometer. The experimental results show that the synthesized compound exhibits typical semectic thermot liquid crystal. Meanwhile, the crystal of the compound was determined by x-ray single crystal diffraction analysis. The crystal of the compound belongs to monoclinic system with space group P2(1)/c, a = 9.586(1) Å, b = 18.391(2) Å, c = 9.433(1)Å, α = 90°, β = 115.816(2)°, γ = 90°, Dc = 1.217 g · cm⁻³, V = 1496.9(3) Å⁻³, and Z = 4.

Keywords:

• 2,6-Bis(benzylidene)cyclohexanone
• liquid crystal intermediate
• rheological property
• texture structure
• x-ray single crystal diffraction

Acknowledgments

This work was supported by the National Natural Science Foundation of China (Grant No. 20673050) and the “Tai-Shan Scholar” Construction Engineering of Shandong Province and the Science and Technology Tackle Key Problems Foundation of Shandong Province (Grant No.2005GG3202084).