Synthesis and Analysis of Halogen Containing Oxadiazole Based Liquid Crystals

Jason Nguyen

Abstract

The phase behavior of altered substituent groups based on 2,5-bis-(p-hydroxyphenyl)-1,3,4-oxadiazole (ODBP) was studied by means of polarized microscopy and differential scanning calorimetry (DSC). Such compounds were halogenated in hopes to lower melting temperatures compared to their previously methylated derivatives. Although the melting temperatures of these new oxadiazole compounds were not significantly lower than the previously synthesized methylated compounds, they showed a nematic phase upon cooling from their liquid phase and were still fluid at significantly lower temperatures. All analogs of the halogenated oxadiazoles synthesized during the summer of 2011 showed only the nematic liquid crystal phase on heating and cooling.