On the analyses of modulated differential scanning calorimetry, Fourier transform infrared spectra and quantum chemical calculations of fluorinated and corresponding unfluorinated polyurethanes, we investigated the effects of fluorination on the intermolecular hydrogen bonds and resulted morphological changes in polyurethanes. The B3LYP/6-31 G(d',p') calculated values supported the experimental results suggesting that the fluorinated hard segment facilitates hydrogen bond interactions towards soft segment polyether, while reducing the strengths within self-associated hard segments. (c) 2006 Elsevier Ltd. All rights reserved.