A new aromatic diamine monomer containing benzoxazole substituents was prepared by a multistep synthesis starting from 1,4-dibromo-2,5-difluorobenzene. The diamine was polymerized with commercial aromatic dianhydride or dicarboxylic acid chloride monomers to provide several different poly(amic acid)s and polyamides with their inherent viscosities in the range of 0.24-0.46 dL/g. Thermal properties of these polymers including thermal imidization of poly(amic acid)s into polyimides were investigated by using FTIR, DSC, and TGA. (C) 2004 Wiley Periodicals, Inc.