A series of isomeric poly(ether ether ketone)s were synthesized using microwave-assisted method by nucleophilic substitution reaction of hydroquinone and 4,4'-biphenol with 4,4'-difluorobenzophenone (DFBP) or 2,4'-DFBP in the presence of anhydrous K2CO3 The polymers with inherent viscosities in the range of 0 20-0 71 dlg(-1) were obtained in quantitative yields and had excellent thermal stability as shown by the temperature of 5% weight loss in nitrogen above 410 degrees C X-ray diffraction patterns confirmed the semicrystalline character of some of the polymers The results also indicate that the reaction time was shortened remarkably and the reaction temperature could be controlled easily POLYM ENG SCI, 51 23-27, 2011 (C) 2010 Society of Plastics Engineers