Sodium dithionite in the presence of NaHCO3, in water acts as a single-electron-transfer agent and facilitates the single-electron-transfer/degenerative-chain-transfer mediated living radical polymerization (SET-DTLRP) of acrylates initiated with iodoform at room temperature. The resulting alpha,w-di(iodo)polyacrylates can be used as macroinitiators for the SET-DTLRP of other acrylates. Ultrahigh-molar-mass poly(tert-butyl acrylate) can be synthesized via the SET-DTLRP of tert-butyl acrylate and has a very low weight-average molecular weight/number-average molecular weight ratio of 1.15. (c) 2005 Wiley Periodicals, Inc.