X-ray photoelectron emission microscopy (X-PEEM) was used to study the surface orientationof stylized and rubbed polyimide thin films. Using soft X-rays produced by a synchrotron light source,this technique combines high spatial resolution imaging with near-edge X-ray absorption fine structure(NEXAFS) spectroscopy to yield information on the surface orientation of the films. Stylizing is an idealmodel of the rubbing process since the local stress acting on the polyimide to orient the molecules can becalculated. The minimum normal stress necessary to orient the surface of BPDA−PDA films was foundto be 45 MPa much lower than the bulk yield stress of 200−300 MPa. Studies of the polyimide filmsoriented by the conventional rubbing method showed lateral inhomogeneities in the orientation of thepolymer at the surface.
