title: Viscosity of two-dimensional suspensions.
abstract: Over a range of conditions, lipid and surfactant monolayers exhibit coexistence of discrete solid domains in a continuous liquid. The surface shear viscosity, mu(s), of such monolayers collapses onto a single curve: mu(s)/mu(so) = [1-(A/A(c))](-1), in which mu(so) is the viscosity of the liquid phase, A is the area fraction of the solid phase measured by fluorescence microscopy, and A(c) is a critical solid phase fraction. This scaling relationship is directly analogous to that of three-dimensional dispersion of spheres in a solvent with long-range repulsive interactions, with area fraction replacing volume fraction.
authors.affiliation: Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, USA.
authors.forename: Junqi
authors.initials: J
authors.lastname: Ding
authors.forename: Heidi E
authors.initials: HE
authors.lastname: Warriner
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Zasadzinski
mesh_terms: D008055:Lipids / Q000737:chemistry*; D008856:Microscopy, Fluorescence; D008956:Models, Chemical; D013501:Surface-Active Agents / Q000737:chemistry*; D013535:Suspensions / Q000737:chemistry*; D014783:Viscosity
chemical_list: D008055:Lipids; D013501:Surface-Active Agents; D013535:Suspensions