FILM-FORMING PROPERTIES OF ASPHALTENES AND RESINS - A COMPARATIVE LANGMUIR-BLODGETT STUDY OF CRUDE OILS FROM NORTH-SEA, EUROPEAN CONTINENT AND VENEZUELA

Asphaltenes and resins were separated from different crude oils, disso lved in different paraffinic and aromatic solvents and studied by mean s of Langmuir technique. It was found that the resin films are more co mpressible and more polar than the corresponding asphaltene films. Int ermolecular aggregation between asphaltene molecules was more prominen t than between resin molecules, and the size of the final aggregates d epended on the nature of the solvent and the bulk concentration of the aggregating species. Even when present in smaller amounts than asphal tenes on the surface, the resins dominate the film properties.