A series of new poly(aryl ether)s containing the pyrimidine moiety were prepared by a nucleophilic aromatic substitution polymerization reaction in an aprotic solvent (DMAc) in the presence of excess potassium carbonate. These polymers are high molecular weight, amorphous, and soluble in common solvents at room temperature. The polymers are easily cast from solution into flexible, colorless, and transparent films. They showed high glass transition temperatures ranging from 198 to 304 degrees C by DSC analysis. The 5% weight losses by thermogravimetric analysis ranged from 478 to 580 degrees C, indicating that these polymers are very thermostable in nitrogen and air.