The cationic polymerization of 1-(2-hydroxyethyl)aziridine was approached by means of several catalytic systems under various conditions in order to obtain a versatile hydroxylated starting material for chemical modification reactions. Largely regular polymers were obtained using BF3 center dot EtNH2 and the selected conditions. The expected head and end groups, a secondary amine and a cyclic or branched quaternary ammonium, respectively, were identified with the aid of NMR. However, in all cases we observed the participation of the primary hydroxyl group in chain transfer reactions, leading to morpholine end groups. Kinetic studies performed during the first 120 min of the reactions showed that the more active the catalytic system, the more irregular the polymer structure. The best results were obtained when polymerization was performed with 1 mol% BF3 center dot EtNH2 in the absence of solvent at 45(degrees)C, which yielded a polymerization degree of about 44 monomeric units. POLYM. ENG. SCI., 54:579-591, 2014. (c) 2013 Society of Plastics Engineers