Observations made using AFM and SEM have been combined in order to study the structure of asphalts. Fluorescence microscopy was used to aid in understanding the structural changes occurring when polymer is added to the asphalts.  With the atomic force microscope we are able to study the structure of the asphalts without any pre‐preparation. Despite very low resolution, our study reveal ed a network of asphaltene molecules with regard to asphalt gel. The same result is obtained by SEM observation but with a much better resolution. SEM observation, however, needs an adequate preparation method.  In the presence of polymer we observed a rearrangement of the initial asphaltene association which leads to the assumption that polymer can aggregate the asphaltene phase.

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Surface functionalization of polyimide films was carried out by cold plasma treatment using a radio frequency discharge and the optimum plasma conditions were evaluated by water contact angle measurements. The relationship between gas permeation behaviour and surface modification of the films was discussed.

Poly(ethylene-co-vinyl alcohol) (EVOH) films with two different ethylene contents (29 and 44 mol %) have been treated by hydrophobic plasma (CF4, tetramethylsilane (TMS), CF4/H2, and CF4/C2H2). Conditions of the cold plasma treatment were optimized by the water contact angle measurements as a function of the different plasma parameters (plasma power, gas flow, and treatment time). Chemical changes of the film surface were characterized by X-ray photoelectron spectroscopy. The obtained results revealed the presence of fluorine containing functional groups such as CF, CF2, and CF3 in the case of CF4, CF4/H2, and CF4/C2H2 plasma treatment and the presence of SiO x C y compounds after TMS treatment. The morphology of the plasma treated EVOH films was examined by atomic force microscopy, which indicated an increase of the film roughness after treatment. Negligible changes of thermal properties of the modified EVOH films were observed by means of the temperature modulated differential scanning calorimetry. The barrier properties of films were characterized by water permeability measurements. It was found that the hydrophobicity was significantly improved after plasma treatment and for some treated films the water permeability was decreased up to 28%.

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