Thursday 26 October 2023
When a pendant drop of crude oil is aged in brine, it can form an interfacial elastic membrane of asphaltenes so stiff that it wrinkles and crumples upon retraction. In early retraction, the interface shows a fluid viscoelasticity measurable using a Gibbs Isotherm or dilatational rheology. Further retraction causes a phase transition to a 2D elastic solid with non-isotropic, non-homogeneous surface stresses. In this regime, we use new techniques in elastic membrane theory to fit for the elasticities of these solid capsules. These elastic measurements can help us develop a deeper understanding not only of crude oil interfaces, but also of the myriad fluid systems with solid interfacial layers.
DOI: 10.1021/acs.langmuir.3c01845
