A 5-membered cyclic alkoxyamine and a 17-membered cyclic alkoxyamine were synthesized and used in the polymerization of styrene. Polymerizations using the 5-membered cyclic alkoxyamine resulted in polymers with uncontrolled molecular weights and high polydispersities. Polymerizations using the 17-membered cyclic alkoxyamine produced oligomeric polymers in which multiple polymer chains are linked through NO-C bonds. EPR homolysis experiments revealed that the 5-membered cyclic alkoxyamine does not dissociate to form a nitroxide species, even at temperatures as high as 403 K. In contrast, the 17-membered cyclic alkoxyamine does dissociate to form nitroxide, but the rate of dissociation is slower than that of parent acyclic alkoxyamine 2,2,5-trimethyl-3-(1-phenylethoxy)-4-phenyl-3-azahexane. (C) 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 8049-8069, 2008