A Molecular Dynamics Study of C12E6 and SDS Surfactants at the Silica-Water and Air-Water Interfaces

Monday, November 9, 2009
Ryman Hall B1/B2 (Gaylord Opryland Hotel)

Liu Shi, School of Chemical Biological and Materials Engineering, The University of Oklahoma, Norman, OK
Naga Rajesh Tummala, School of Chemical Biological and Materials Engineering, The University of Oklahoma, Norman, OK
Alberto Striolo, School of Chemical Biological and Materials Engineering, The University of Oklahoma, Norman, OK

NVT molecular dynamics simulations have been carried out to investigate the adsorptions of hexaethylene glycol monododecyl ether (C12E6) and sodium dodecyl sulfate (SDS) surfactants at the silicon dioxide-water and water-air interfaces. The simulations were performed at room temperature and at different surfactant coverages, from an infinite-diluted coverage to full monolayer. We will discuss structural and dynamic properties of the molecular adsorption of surfactants by presenting results for density profiles, end-to-end distances, tilt angles, radial distribution functions, and mean square displacement of both water and surfactants. The results show an entangled structure of surfactant chains at both silica-water and air water interfaces and the interface properties are dependent of the degree of coverage. The simulations will be compared to experimental data obtained as a function of the density of surfactant molecules per unit interfacial surface area. The results are expected to secure advances in novel technologies such as admicellar polymerization.
Extended Abstract: File Not Uploaded
See more of this Session: Poster Session: Interfacial Phenomena
See more of this Group/Topical: Engineering Sciences and Fundamentals