interfacial tension

Розроблено рекомендації щодо поєднання в нормативному документі вимог контролю ступеня захищеності підземних трубопроводів із сталі в корозійному середовищі з позицій електрохімії і механіки деформівного твердого тіла
***Recommendations in relation to combination in the normative document of requirements in relation to control of degree of security of underground pipelines from steel in a corrosive environment from positions of electrochemistry and mechanics of deformable solid are worked out***

Three different macromolecular structures of poly(ethylene oxide-b-propylene oxide) copolymers, used in formulations of commercial demulsifiers for breaking water-in-crude oil emulsions, were investigated. The interfacial activity (), the lower interfacial tension (m), the critical micelle concentration (CMC), the interfacial concentration (Γ) and the molecular area (A) adsorbed at the interface of the surfactant solutions were evaluated. These results were correlated to surfactant performance in coalescing three different asphaltene model emulsions.

The formation of aggregates of a fraction of asphaltenes extracted from Brazilian crude oil was investigated by measuring the interfacial tension and kinematic viscosity of their solutions prepared in different solvents. The interfacial tension results indicate the existence of critical micelle concentration (CMC) levels of the asphaltenes in solvents with solubility parameters sufficiently different from those of the asphaltene tested. The kinematic viscosity measures revealed the formation of aggregates at concentrations above the CMC.

The physico-chemical regularities of polypropylene microfibers obtained via processing polypropylene/copolyamide (PP/CPA) mixture melts filled with nanosilicas have been investigated. It has been shown that the chemical nature of silica functional groups affects the viscosity of PP/CPA melts. In spite of the solid state of additives the filling effect does not occur or reveals weakly. Silicas do not prevent the polypropylene fiber-forming in a copolyamide matrix but improve it. This is explained by the stabilizing action of silica additives on PP liquid streams.