Adsorbed polymer-surfactant layer structure probed using atomic force microscopy

COLL 7

Emily Meyer1, Nick Ainger2, Neil Shaw2, and Raymond Dagastine1. (1) Department of Chemical and Biomolecular Engineering, University of Melbourne, Particulate Fluids Processing Center, Melbourne, Australia, (2) Unilever, Port Sunlight, United Kingdom
The remarkable number of behaviors of polymer-surfactant complexes has lead to their use in a wide range of applications in personal care products, food formulations and pharmaceuticals. There has been considerable study of oppositely charged polymer-surfactant complexes in solution and, more recently, the behavior of such complexes and their components on surfaces have also been considered. However, little attention has been given to the dynamics process by which the interaction forces between adsorbed layers transition with bulk concentration changes. In this work we use atomic force microscope (AFM) to investigate the properties of adsorbed polymer-surfactant complexes using anionic surfactants and guar based cationic polyelectrolytes. Force versus separation data obtained with the AFM allow one to determine the adhesive properties of the system, conformational changes within the layer, and the dynamics of how these changes are occurring as a function of bulk surfactant and electrolyte concentrations.
 

Surfactants from Renewable Resources
9:00 AM-12:20 PM, Sunday, April 6, 2008 Morial Convention Center -- Rm. 225, Oral

Division of Colloid & Surface Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008