The inhibition effect of the grape pomace extract during the early stage of steel corrosion under adsorbed thin electrolyte layers was investigated. The present study was carried out to identify the components present in the 2-propanol grape pomace extract by GC-MS analysis. Gravimetric, electrochemical impedance spectroscopy, potentiodynamic polarization, scanning electron microscopy, and FTIR techniques were used to study the corrosion inhibitive. Polarization measurements have indicated that these green inhibitors acted through mixed type inhibition. SEM studies have evidenced the formation of a protective film over metal surface while FTIR supported by molecular modelling has proved that this shielding effect was caused by aldehydes particularly 2-phenylacetaldehyde and 3,7-dimethylocta-2,6-dienal.

Stöber silica particles having diameters of ca. 100 and ca. 200 nm were prepared and silylated using trimethylsilyl N,N-dimethylcarbamate, achieving a range of surface coverage by trimethylsilyl groups by varying the amounts of silylating agent used. The efficacy of silylation was characterized in terms of hydrophobicity of the particles which was assessed by film balance investigations at water−air interfaces and additionally by imaging the long- and short-range structures of silica particulate layers at water−air interfaces and on mica supports by using Brewster-angle and atomic force microscopies.

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Morphological and chemical changes of the surface of low-density polyethylene (LDPE), linear middle-density polyethylene (L-MDPE), and their 80/20 blend were studied by different techniques after corona-discharge treatment in air and subsequent annealing. The surface tension was determined by wetting; the roughness was measured by atomic force microscope (AFM), and the surface chemical composition was analyzed by X-ray photoelectron spectroscopy (XPS), whereas the low-molecularmass fraction washed off by chloroform by FTIR. The surface tension of the films increases with the electrode current. The surface roughness depends primarily on the polymer type and is less affected by the corona treatment. At the initial stage of annealing, posttreatment-type oxidation and hydrophobic recovery are competing. The former is more pronounced in L-MDPE, the latter in LDPE. After annealing at 50°C for 160 days, hydrophobic recovery becomes predominant in each film studied, which is accompanied by significant smoothening of the surface. According to XPS and FTIR results, this is due to the migration of low-molecular-mass components (oligomers, oxidized polymer fractions, and additives) to the surface.

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