Two new bis(ether acyl chloride)s, 1,1-bis[4-(4-chloroformylphenoxy)phenyl]-1-phenylethane and 1,1-bis[4-(4-chloroformylphenoxy)phenyl]-1-phenyl-2,2,2-trifluoroethane, were prepared from readily available reagents. Aromatic polybenzoxazoles with both ether and phenylethylidene or 1-phenyl-2,2,2-trifluoroethylidene linkages between phenylene units were obtained by a conventional two-step procedure including the low-temperature solution polycondensation of the bis(ether acyl chloride)s with three bis(o-aminophenol)s, yielding poly(o-hydroxyamide) precursors, and subsequent thermal cyclodehydration. The intermediate poly(o-hydroxyamide)s exhibited inherent viscosities of 0.39-0.98 dL/g. All of the poly(o-hydroxyamide)s were amorphous and soluble in polar organic solvents such as N, N-dimethylacetamide, and most of them could afford flexible and tough films via solvent casting. The poly(o-hydroxyamide)s exhibited glass-transition temperatures (T-g's) of 129-194 degreesC and could be thermally converted into corresponding polybenzoxazoles in the solid state at temperatures higher than 300 degreesC. All the polybenzoxazoles were amorphous and showed an enhanced T-g but a dramatically decreased solubility with to respect to their poly(o-hydroxyamide) precursors. They exhibited T-g's of 216-236 degreesC through differential scanning calorimetry and were stable up to 500 degreesC in nitrogen or air, with 10% weight-loss temperatures being recorded between 538 and 562 degreesC in nitrogen or air. (C) 2003 Wiley Periodicals, Inc.