5.5',6,6'-Tetrahydroxy-3,3,3',3'-tetramethyl spirobisindane (TTSBI) was polycondensed with 4,4'-difluorodiphenylsulfone (DFDPS) in DMSO with K2CO3 as catalyst and azeotopic removal of water. The feed ratio of DFDPS/TTSBI was varied from 1.0/1.0 to 2.0/1.0 at concentrations avoiding gelation. At feed ratios around 1.0/1.0 hyperbranched polymers were a minority and cyclic poly(ether sulfone)s were the predominant reaction products. With increasing feed ratio of DFDPS more and more multicyclic polymers were formed, and at a feed ratio of 1.9/1.0 perfect multicycles free of functional groups were the vast majority of the reaction product. Despite variation of the reaction conditions quantitative conversion was not achieved. (c) 2007 Wiley Periodicals, Inc.