TEM and AFM of Fine Structure in Polymer Friction-Transfer Layers.

Oriented films of PTFE, UHMWPE and Vectra, TM prepared by friction transfer, have been investigated using transmission electron microscopy (TEM) and atomic force microscopy (AFM), and the results have been compared. These techniques can provide molecular resolution of the internal structure and the sample surface respectively, with certain limitations. Molecular imaging with AFM has the advantage of not being limited to crystallographic planes showing strong Bragg reflections and belonging to zones whose axis is parallel to the observation direction. On the other hand, high-resolution AFM images generally correspond to very restricted sample areas (typically≤200nm2), so that large numbers of images may be necessary to obtain a reasonable representation of a heterogeneous sample surface.