THE PREPARATION AND CHARACTERIZATION OF NOVEL BIPHENYL GROUP-CONTAINING POLYESTER SYSTEMS

A series of copolymers based on the rigid biphenyl unit has been prepared either by a non-aqueous dispersion (NAD) process or by a Schotten-Baumann modification. In these studies, comparisons of the performance of polymers containing the 1,1 biphenyl unit with that of model compounds have been made. Characterisation of the biphenylic esters reveals that they are most thermally stable and possess more associated order than the equivalent polymers prepared using model compounds. The ester products obtained from Schotten Baumann modification show interesting thermal behaviour. Thermotropic liquid crystalline materials were obtained from reactions of terephthaloyldioxydibenzoyl chloride with diols and from reactions of terephthaloyldioxydibenzoyl choride with 4,4' dihydroxybiphenyl/ethylene oxide condensates.