Molecular Crystals and Liquid Crystals, Vol.587, No.1, 41-53, 2013
Synthesis of Banana-Shaped Liquid Crystals for Photoswitching Properties
Three banana-shaped monomers containing naphthalene as central units and azobenzene in side arms with terminal alkenes were synthesized and characterized. DSC, polarizing optical microscopy, and X-ray diffraction measurements prove that all compounds exhibit B-6 phase. The trans-azobenzene showed high-intensity -* transition at about 365nm and low-intensity n-* transition at about 450nm. The strong photoisomerization behavior in solutions of the molecules displayed that trans to cis isomerization takes 45 sec whereas reverse process takes about 28h and 30min. This long thermal back relaxation is useful for creation of optical image storage.