title: Dynamics of surfactant-driven fracture of particle rafts.
abstract: We investigate the dynamic fracture of a close-packed monolayer of particles, or particle raft, floating at a liquid-gas interface induced by the localized addition of surfactant. Unusually for a two-dimensional solid, our experiments show that the speed of crack propagation here is not affected by the elastic properties of the raft. Instead it is controlled by the rate at which surfactant is advected to the crack tip by means of the induced Marangoni flows. Further, the velocity of propagation is not constant in time and the length of the crack scales as t(3/4). More broadly, this surfactant-induced rupture of interfacial rafts suggests ways to manipulate them for applications.
authors.affiliation: Division of Engineering and Applied Sciences, Harvard University, Pierce Hall, Cambridge Massachusetts 02138, USA.
authors.forename: Dominic
authors.initials: D
authors.lastname: Vella
authors.forename: Ho-Young
authors.initials: HY
authors.lastname: Kim
authors.forename: Pascale
authors.initials: P
authors.lastname: Aussillous
authors.forename: L
authors.initials: L
authors.lastname: Mahadevan
mesh_terms: D000388:Air; D004548:Elasticity; D005990:Glycerol / Q000737:chemistry; D008433:Mathematics; D016012:Poisson Distribution; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry*; D014783:Viscosity; D014867:Water / Q000737:chemistry
chemical_list: D013501:Surface-Active Agents; D014867:Water; D005990:Glycerol