Difference between revisions of "Restructuring of Hydrophobic Surfaces Created by Surfactant Adsorption to Mica Surfaces"
Line 15: | Line 15: | ||
== Simulations and results == | == Simulations and results == | ||
− | [[Image:Surfactant_1.jpg| | + | [[Image:Surfactant_1.jpg|200px|thumb|left|'''Fig.1 ''' Initial structure of the simulated model. Green spheres: surfactant headgroups; blue licorice: surfactant tails; red spheres: chloride ions; tan spheres: potassium ions; magenta licorice: mica sheets; gray CPK: water box.]] |
Revision as of 03:22, 26 October 2011
Entry by Yuhang Jin, AP225 Fall 2011
Reference
Jhuma Das, Changsun Eun, Susan Perkin, and Max L. Berkowitz, Langmuir, 2011, 27, 11737.
Keywords
Surfactant monolayer, hydrophobic surfaces, long-range electrostatic interaction, molecular dynamics simulation
Introduction
Hydrophobic interaction acting between surfaces is important in many fields and applications. Sometimes this interaction can act over distances as large as ~50 nm, probably due to the existence of submicroscopic bubbles, cavitation in the intervening fluid, or electrostatic interactions between charged patch of restructured hydrophobic surfaces created by surfactant adsorption to mica. Using a surface force balance (SFB), one can measure the interaction between hydrophobic surfaces created by placing ionic surfactants on mica. The interaction sometimes displays a long-ranged hydrophobic component owing to the coexistence of both negatively charged bare mica patches exposed to water and positively charged patches covered by a surfactant bilayer. In this paper, computer simulations confirmed this picture and studied how this restructuring depends on the properties of the surfactant molecules.