Abstract: The poly(ethylene glycol) polyurethaneureas (PEUU) and the complexes composed of thePEUU and LiClO₄ were examined by means of XPS and DSC. The DSC studies indicatethat the soft segment's Tg of the complexes increases with increasing LiClO₄ concentration;it shows that LiClO₄ dissolves selectively in the poly (ethylene glycol) (PEG) phase. TheXPS data show that the soft segment of PEG is significantly richer on the surface. Beingadded to PEUU, LiClO₄ is advantageous to the further enrichment of PEG on the surface.It is also an evidence of selective dissolvation of LiClO₄ in the PEG phase.

Key words: polyether polyurethaneurea, polymer solid ionic ocnductor, X-ray photoelectron spectrosoopy