Thermal properties of some fully aromatic thermotropic liquid crystal polyesters

Wholly aromatic liquid crystalline main chain polyesters derived from terephthalic acid, phenyl‐ or (1‐phenylethyl)hydroquinone modified with either 3,4′‐ or 4,4′‐dicarboxydiphenylether and p‐hydroxybenzoic acid, have been prepared by acidolysis and thermally investigated. All prepared polyesters exhibit excellent thermal stability up to about 400°C, however, the (1‐phenylethyl)hydroquinone polyesters generally showed lower stability. Melting points could be decreased to around 200°C without any decrease in the thermal stability or the nematic range.