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The rheological behavior of a branched polymer melt is studied theoretically, based on the extension of the primitive path and tube model. We have developed the method to evaluate the stress relaxation moduli and the viscosity of a comb polymer melt and to find out how the result is affected by various improvements in the theory. A carefully calculated form of the path length effective potential is used, including the logarithmic term (which can be derived from a detailed description of the relaxation of a branch) and also allowing for tube dilation (i.e., we take into account that constraint release speeds up reptation).Two qualitatively different types of long-time behavior are predicted, depending on whether the comb backbones are self-entangled or not. Both have already been observed in previously published data.

This article investigates the modification of a carbon steel surface by benzotriazole (BTA), and the structure and properties of the formed layers. Adsorption was studied by surface analytical methods such as X-ray photoelectron spectroscopy (XPS) and reflecting infrared microscopy (FTIR). It has been established that a polymer-like film containing iron-azole complexes that are 2 nm thick and strongly bonded to the metal is formed on the surface as a result of the azole interacting with a steel surface. This film is capable to inhibit uniform and localized corrosion of steel in neutral aqueous electrolytes containing chloride ions. It is shown that the iron-azole layer located at the interface acts as a promotor of adhesion, increasing the interaction of polymeric coatings with the steel surface. Taking into account these properties, the steel pretreatments can be used for improving the anticorrosion properties of polymeric coatings applied for the protection of steel constructions.

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