4,4'-bis(Phenoxy)diphenyl sulfone (DPODPS) was synthesized by reaction of phenol with bis(4-chlorophenyl) sulfone in tetramethylene sulfone in the presence of NaOH. Two poly(aryl ether sulfone ether ketone ketone)s (PESKKs) with high molecular weight were prepared by low temperature solution polycondensation of DPODPS and terephthaloyl chloride (TPC) or isophthaloyl chloride (IPC), respectively, in 1,2-dichloroethane and in the presence of aluminum chloride (AlCl3) and N-methylpyrrolidone (NMP). The resulting polymers were characterized by various analytical techniques, such as FT-IR, H-1-NMR, DSC, TG, and WAXD. The results show that the T-g and T-d of PESEKKs are much higher, but its T-m is lower than those of PEKK. The other results indicate that PESEKKs exhibit excellent thermostabilities at 300 +/- 10degreesC. (C) 2005 Wiley Periodicals, Inc.