Alcohol-terminated telechelic polyoxetanes with sernifluorinated (FOx) and alkyl ether pendant groups (ME20x) were synthesized and characterized. These are amphiphilic telechelics by virtue of incorporation of both hydrophilic and hydrophobic repeat units. The ME20x/FOx telechelic copolymers were characterized by NMR spectroscopy for composition and molecular weight through end-group analysis. Differential scanning calorimetry revealed decreasing T-g with increasing incorporation of ME20x and provided evidence for copolymer structure. Monomer reactivity ratios were determined in two solvents with different polarity. In methylene chloride, an active end derived from 5FOx monomer reacts preferentially with ME20x whereas the ME20x-derived end shows no selectively. The reactivity ratios are 0.97 for ME20x and 0.12 for 5FOx. In methylcyclohexane, the monomer reactivity ratios are more characteristic of ideal copolymerization. The parameters are 1.65 for ME20x and 0.49 for 5FOx.