Polarized NEXAFS studies on the mechanical rubbing effect of poly(tetrafluoroethylene) oligomer and its model compound

The structural change of the evaporated perfluorotetracosane (PFT) n-CF3(CF2)(22)CF3 and poly (tetrafluoroethylene) (PTFE)(CF2)(n) films by the mechanical rubbing process was examined with use of NEXAFS spectroscopy. In the PTFE film, the chains were almost parallel to the surface and were uniaxially realigned along the rubbing direction, while the chains in the PFT film after evaporation were oriented normal to the surface, and the orientation was hardly affected by the rubbing process. The chains of the PFT evaporated on the rubbed PTFE film aligned along the rubbing direction.