Poly(ethylene oxide) (PEO), poly(acrylic acid) (PA), dextran, and some oligomeric saccharides were found to be adsorbed from the aqueous phase on a dealuminated FAU-type zeolite (Si/Al = 110). PEO was also adsorbed on a MFI-type zeolite (Si/Al > 1000), but dextran was not. Inulin and levan were excluded from the FAU-type zeolite. Addition of ethanol (dextran) or increase of pH (PA) caused a strong decrease of the adsorption equilibrium. The Fickian diffusity D of the trimer of dextran (isomaltotriose, M w = 504) related to that in the aqueous bulk phase D 0 was D/ D 0 = 10-3 and decreased to D/D 0 = 10-8 at M w = 40 000. D/D 0 values for PEO (M w = 9000, 20 000, and 40 000) in the FAU zeolite were situated between 2 and 5 × 10-7. The high specific interaction indicates that the polymer not only is deposited on the surface of the zeolite crystal but must penetrate to some extent into the pores. The FAU zeolite can selectively adsorb oligomers and polymers containing α(1−6) glycosidic linkages (raffinose, stachyose, isomaltotriose, dextran) while those built up by β(1−6) or α,β(1−4) bonds are sterically excluded.

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CH(x) films on silicon substrates deposited by a Mesh Hollow Cathode Process (MHC) were analyzed by various techniques. The films were produced with varying deposition times, resulting in thicknesses ranging from ~2-20 nm. X-Ray Reflectivity (XRR) was used to determine the film thicknesses and the deposition rate. A good correlation of measured XRR thicknesses with SIMS sputter depths down to the film-substrate transition was found. An AFM-based nanoscratching technique was applied to test the wear resistance of the thin overcoats. The MHC films reveal slightly decreasing scratch resistance for reduced film thicknesses, which can be explained by a higher fraction of soft interface zones for thinner films. This is in accordance with Raman spectroscopic measurements in the visible spectral range which were carried out to examine the carbon bonding properties. Combined analysis of G peak position and D/G peak intensity ratio indicates a more graphitic structure for film thicknesses less than 10 nm.