Heterobifunctional poly(ethylene oxide): synthesis of alpha-methoxy-omega-amino and alpha-hydroxy-omega-amino PEOs with the same molecular weights.

Well-defined alpha-methoxy-omega-amino and a alpha-hydroxy-omega-amino poly(ethylene oxide)s (PEOs) were obtained after chemical modifications of alpha-hydroxy-omega-allyl PEO which was synthesized by anionic polymerization of ethylene oxide (EO) with allyl alcoholate as initiator; molecular weights of the prepolymer were controlled by the monomer/initiator ratio. Addition of methyl iodide on the hydroxy function of this prepolymer led to an alpha-methoxy-omega-allyl PEO; completion of the reaction and purity of the resulting polymer were demonstrated by 1H, 13C NMR and GPC studies. Addition reactions of 2-amino-ethanethiol hydrochloride on alpha-hydroxy-omega-allyl PEO and alpha-methoxy-omega-allyl PEO in the presence of azobisisobutyronitrile (AIBN) led to the expected homopolymers without any side reactions as shown by 1H and 13C NMR spectra.