The synthesis of hydroxy-terminated poly(2,2-substituted-1,3-propylene oxide) polyoxetane telechelics and co-telechelics bearing semifluorinated (-CH2OCH2(CF2)(n)CF3) and functional bromomethyl pendant groups is reported. Characterization utilized H-1 NMR spectroscopy, temperature modulated DSC (MDCS), and gel permeation chromatography (GPC). Analysis of relative reactivity ratios for a 1:1 3FOx to BrOx feed indicates that in the early stages of reaction BrOx-BrOx dyad mole fraction is below the statistically predicted amount. However, a model suggests that the final telechelic dyad composition at complete reaction is not very different from a statistical copolymer. The co-telechelics have low T(g)s (-33 to -39 degrees C) and molecular weight in a desirable range (M-w approximate to 3-5 k). Telechelics were incorporated in polyurethanes (PUs) with isophorone diisocyanate (IPDI) and butanediol (BD) as the hard block. Characterization of polyurethane composition and bulk properties by H-1 NMR, MDSC, and GPC is described. The new polyurethanes hold promise for a 'reaction on polymer' approach to polyurethanes with functional soft blocks. (c) 2005 Elsevier Ltd. All rights reserved.