Original Articles: 2012 Vol: 4 Issue: 5
Symmetric liquid crystal trimer containing bisazobenzene moieties: Synthesis and Mesomorphic Properties.
Abstract
A new system of liquid crystal trimer containing bisazobenzene groups and biphenyl core has been synthesized by diazotization and coupling of primary aromatic amine and subsequent etherification with polymethylene spacer group and further etherification to react to the biphenyl core. The material was characterized using spectroscopic methods and X-ray diffraction. The spacer length was found to exert a profound influence on the clearing temperatures of these materials and a large odd-even effect was observed for the series. The smectic A phase stability was observed to increase with the increasing spacer length. X-ray diffraction has revealed the structure of the smectic A phase of the representative symmetric bisazobenzene trimers to be of the monolayer type and not intercalated.