Macromolecular Rapid Communications, Vol.20, No.9, 497-504, 1999
XPS and ATR surface studies of block copolyurethanes based on 1,2-ethylene bis(4-phenyl isocyanate)
The surface properties of two block copolyurethanes based on 1,2-ethylene bis(4-phenyl isocyanate) (P2PDI), poly(tetramethylene ether glycol) (PTMG) or poly(propylene glycol) (PPG), and ethylene diamine, were investigated by attenuated total reflectance (ATR) infrared spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis. The air-facing surfaces (AFS) of both materials are more abundant in the PPG or PTMG soft segment. More PTMG present on AFS indicates that the PTMG soft segment is more hydrophobic than PPG. Besides, the ATR spectra revealed that more phase mixing occurs in the near-surface region than in the bulk and the domain/matrix interface tends to orient to this region for both samples.