Synthesis and Mesomorphism of a Triphenylene-Based Discotic Mesogenic Polymer Obtained from Anionic Polymerization

Abstract

The discotic liquid crystals composed of a rigid aromatic core and peripheral flexible side chains, are easy to be stacked into a one-dimensional ordered column structures by π–π interactions [1, 2, 3]. Although the discotic liquid crystals have been studied for many years, the research on discotic liquid crystal polymer (DLCP) is still fundamental, and its performance has not been studied widely in the fields of organic electronics and optoelectronics, such as the application of field-effect transistors, light-emitting diodes, and photovoltaic solar cells. To enrich the studies of the properties of discotic liquid crystal polymers, here we have successfully prepared poly {[3,6,7,10,11-pentakis(hexyloxy)-2-oxytriphenylene] methacrylate} (PMTS) via anionic polymerization for the first time. The chemical structure of the polymer was determined by FT-IR and 1H-NMR. The molecular weight of the polymer PMTS was characterized by Gel Permeation Chromatography (GPC). Its number average molecular weight was approximately 32,000 while its weight-average molecular weight was about 36000. The distribution of the molecular weight was 1.4. And then, their thermodynamics and liquid crystal properties were studied by polarizing optical microscopy (POM) and differential scanning calorimetry (DSC).