Many belong to an aromatic polyester liquid crystal polymers, because the ester bond is a flexible linear, easily meet the requirements of liquid crystal structure, so the vast majority are polyimide liquid crystal polyester imide. From acid imide or bisphenol-generation unit starting structure can get a lot of different polyester imide. However, these polymers can exhibit liquid crystalline behavior of the polymer but not much. One reason is that these polymers have a high melting point, decomposition has occurred prior to its liquid crystal state may occur. At the same time these polymers are often difficult to dissolve. Impossible to observe whether the lyotropic liquid crystalline behavior.