Nonpolar hydrophobic soft segments were synthetically incorporated into polyurethanes based on 4,4’-methylenebis(phenyl isocyanate) (MDI)/hexafluoro-1,5-pentanediol (FP)/poly(tetramethylene glycol) (PTMO). The soft segments incorporated were dihydroxy-terminated poly(dimethylsiloxane) (PDMS) and polyisobutylene (PIB). All soft segments have similar molecular weights (M(n) almost-equal-to approximately 2000). All polymers prepared also have similar levels of hard segment (approximately 55 wt %), and they are soluble in common organic solvents. The solvent-cast polymers were studied by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry, electron spectroscopy for chemical analysis (ESCA), and static secondary-ion mass spectrometry (SSIMS). The FTIR analysis showed that the absorption band at 3295 cm-1 is important for the interpretation of soft-segment mixing behavior in segmented poly(ether urethanes). The surface analysis data revealed that the incorporation of 20 wt % or less of PIB or PDMS in the soft segment may be sufficient to completely cover the polymer surface with each corresponding soft segment. The PDMS polyurethanes exhibited a pronounced casting solvent dependence on the surface and bulk structure, while the PIB polyurethanes showed less dependence on casting solvent.