title: Effect of temperature on morphologies of evaporation-triggered asphaltene nanoaggregates.
abstract: We use atomic force microscopy to observe the structural changes in petroleum-asphaltene aggregates in air as a function of temperature. The aggregates are obtained by evaporating a toluene solution containing asphaltene. Increase in temperature leads to transition from self-assembled fractal structures to substantially larger mobile "liquid-like" domains that show distinct tendencies of substrate repulsion and self-coalescence. This new aggregation dynamics of asphaltene can be explained by temperature-induced transition of asphaltene from pure amorphous to liquid crystalline phase. Observation of this new phenomenon for asphaltene will have wide implications for asphaltene handling and separation.
authors.affiliation: Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta, Canada.
authors.forename: Mahsa
authors.initials: M
authors.lastname: Mehranfar
authors.forename: Ravi
authors.initials: R
authors.lastname: Gaikwad
authors.forename: Siddhartha
authors.initials: S
authors.lastname: Das
authors.forename: Sushanta K
authors.initials: SK
authors.lastname: Mitra
authors.forename: Thomas
authors.initials: T
authors.lastname: Thundat