Materials with low surface energy are very important in applications that require reduced wetting or adhesion. Monolayers of -CF3 containing compounds possess the smallest surface energy known until now that has to promote surface investigations. Perfluoroalkyl compounds were shown to form a microphase-separated structure due to the immiscibility between the -(CF2)(m)- and the -(CH2)(n)- part. Basing on this concept polyesters with perfluoroalkyl side chains were synthesized. Combined investigations by means of X-ray scattering, molecular modeling, AFM and contact angle measurements were performed to characterize the influence of preparation as well as treatment of spin-coated films and to find a correlation between bulk and surface structure and surface free energy.