Effect of methylene lengths of 4-(ω-(methylimidazole)-alkyloxy)-4’-(cyano)-biphenyl on cellulose liquid crystal solution and its phase transition properties
Cellulose liquid crystal solutions have been extensively studied, and the methylene length of mesogenic units has a significant influence on the properties of cellulose liquid crystal solutions. In this study, 4-(ω-(methylimidazole)alkyloxy)-4’-(cyano)-biphenyl (CBP-n) with 4–7 methylene lengths were synthesized as mesogenic units to prepare cellulose side chain liquid crystal in 1-Allyl-3-methylimidazolium chloride (AMIMCl). And their liquid crystal properties were studied by differential scanning calorimetry (DSC), in-situ infrared spectrometer (IR), torque rheometer, and polarizing microscope (POM). The results showed that CBP-n with 4–7 methylene lengths were thermotropic liquid crystal, and the cellulose/CBP-n/AMIMCl solutions were lyotropic liquid crystal when the concentration of cellulose is 6wt% and the concentration of CBP-n with methylene length 4 and 6 is 3wt%. In-situ IR proved that the liquid crystal formation of cellulose/CBP-n/AMIMCl solution was caused by the hydrogen bonding formed between cellulose and CBP-n. And the solutions have a fewer entanglement number and lower viscosity than those of methylene length 5 and 7, indicating that the hydrogen bonding interaction between CBP-n with even methylene length and cellulose molecule is stronger than that of odd methylene length. This study provides a new approach to produce cellulose fibers using cellulose/CBP-n/AMIMCl as a new renewable resource.
危险品化学品经营许可证（带存储）