Poly(N‐vinylimidazole) based hydrogen bonded side chain liquid crystalline polymer

Abstract

AbstractA new poly(N‐vinylimidazole) (PVI) based side chain liquid crystalline polymer (HB‐PLC) was prepared from PVI as a hydrogen bond acceptor polymer and 11‐(4‐cyanobiphenyl‐4′‐oxy)undekan‐1‐ol (LC11) by molecular self‐assembly processes via hydrogen bond formation between nitrogen of PVI and hydroxyl group of the LC11. The formation of H‐bond was confirmed by using FTIR spectroscopy. The liquid crystalline behavior of the HB‐PLC was investigated by differential scanning calorimeter (DSC) and polarized optical microscopy. The thermal behaviors of the H‐bonded liquid crystalline polymer were investigated by DSC measurements under various heating rates. The HB‐PLC shows a transition temperature of 97°C with an relatively high enthalpy change of 140.6 J/g corresponding to the transition from liquid crystalline nematic phase to isotropic phase. The activation energy required for liquid crystal phase transformation was found to be 551.75 kJ/mol. Copyright © 2010 John Wiley & Sons, Ltd.