Three homopolyesters were prepared by polycondensation of 4,4＇-dihydroxybiphenyl and 2,5-bis(n-octyloxy)-, 2,5-bis(dodecyloxy)- or 2,5-(hexadecyloxy)terephthaloylchloride. Furthermore, several copolyesters were synthesized from 4,4＇-dihydroxybiphenyl and mixtures of 2,5-bis(hexadecyloxy)terephthaloylchloride and 2,5-bis((S)isopentyloxy)terephthaloylchloride. All polyesters were characterized by inherent viscosities, elemental analyses, H-1 n.m.r. spectroscopy, d.s.c. measurements, dynamic mechanical analyses (DMA), WAXS powder patterns at various temperatures and optical microscopy. Two liquid crystalline (LC) phases were detected for the homopolyesters and most copolyesters : a viscous sanidic (biaxial nematic) phase and, at higher temperatures, a mobile nematic phase. The chiral copolyesters displayed an unusual ＇sausage texture＇, but never a Grandjean texture. A chiral nematic phase with helical main chains is discussed.