To improve the mechanical and surface properties of poly(etherurethane) (PEU), multi-walled carbon nanotubes (MWCNTs) were surface grafted by 3,3,4,4, 5,5,6,6,7,7,8,8,8-tridecafluoro-1-octanol (TDFOL) (MWCNT-TDFOL) and used as reinforcing agent for PEU. Fourier-transform infrared spectroscopy revealed the successful grafting of MWCNTs. PEU filled with MWCNT-TDFOL could be well dispersed in tetrahydrofuran solution, and tensile stress-strain results and dynamic mechanical analysis showed a remarkable increase in mechanical properties of PEU by adding a small amount of MWCNT-TDFOL. Contact angle testing displayed a limited improvement (just 9 degrees) in the hydrophobicity of PEU surface by solution blending with MWCNT-TDFOL. However, a large improvement of surface hydrophobicity was observed by directly depositing MWCNT-TDFOL powder on PEU surface, and the water contact angle was increased from 80 degrees to 138 degrees. Our work demonstrated a new way for the modification of carbon nanotubes and for the property improvement of PEU. (C) 2008 Wiley Periodicals, Inc.