Study of telechelic polyurethane with perfluoropolyether tails

Well architectured polyurethanes containing fluorine are expected to be applied in medical devices as well as other fields. A telechelic polyurethane end-capped with perfluoropolyether segments was prepared from polyether glycol as a soft segment, 4, 4'-methylene-bis-(phenylisocyanate), and mono-functional perfluorinated oligomer. The telechelic polyurethane was studied by Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TCA), X-ray photoelectron spectroscopy (XPS), contact angle and atomic force microscopy (AFM). XPS results indicated that the surface of the fluorine containing polyurethane was enriched with fluorine component. It exhibited a hydrophobic property with a water contact angle of 113 degrees. The polyurethane terminated with perfluoropolyether segments showed a better thermal stability. A mechanism was proposed to explain thermal decomposition of polyurethanes. DSC results suggested that the tail-like perfluoropolyether segments would disrupt main chain packing, then raise crystallization potential barrier, and the perfluoropolyether segments did not affect the bulk microphase-separated structure. (C) 2010 Elsevier Ltd. All rights reserved.