VISCO-ELASTICITY OF MONOMOLECULAR FILMS CONTAINING PETROLEUM AMPHIPHILICS

Abstract

Interfacial phenomena are present in many processes of the petroleum production and transportation. Asphaltenes and resins are oil fractions composed of macromolecular structures with greatest polarity and greatest interfacial activity. Specially, asphaltene has been extensively investigated with regard to its colloidal characteristics because of the effects on the formation and stabilization of emulsions and foams, wettability inversion, deposition and adhesion on solid surfaces. The present research project aims to study the properties of amphiphilic components extracted from petroleum at water-air interfaces. Specifically, the investigation intends to describe the phase behavior and the interfacial viscoelasticity of monolayers containing asphaltenes and maltenes. The investigation has been motivated by the promisor results obtained by the current proposal's author from his previous project FAPESP 2013/25880-3. These results identified the phase transition points and the elasticity changes of asphaltene films in air-water interface. The description of the phase behavior and the determination of the interfacial elasticity of asphaltenes films should contribute to the assessment of the rheological behavior and the stability of petroleum emulsions. The experimental methodology includes the extraction and characterization of asphaltenes and maltenes, their solubilization in organic solvents, and the investigation of interfacial film properties through experimental measurements of dynamic interfacial tension and film surface pressure. (AU)