Thermal homeotropic self-alignment on a single substrate of new series of discotic nematic triphenylene-based main-chain polyesters

Abstract

We present the synthesis, characterization, and study of Liquid Crystal properties of a new series of polyesters containing 2,7-di-functionalized triphenylene units in the main chain, whose distinctive feature is that the carboxyl moiety is distant from the aromatic core. Several molecular aspects, such as the distance between the carboxylic group to the core, the length of the connector, and the orientation of the carboxyls were analyzed. In addition, we have investigated the influence of these molecular parameters on the thermal self-alignment of the polymers on different substrates. We have found a simple method to obtain a monodomain homeotropic orientation of these polyesters on a single substrate.