Thin Film Formation of Silica Nanoparticles in the Presence of Lipids at the Fluid-Fluid Interface

Wednesday, November 10, 2010: 8:55 AM
251 C Room (Salt Palace Convention Center)
Michael Maas and Gerald G. Fuller, Chemical Engineering, Stanford University, Stanford, CA

The self-assembly of nanoparticles leads to the formation of ordered structures on meso- or macroscopic scales and thus combines the advantages of large scale structures with the special properties of the nanoscale. In this respect it is of foremost interest to investigate new ways for the preparation of self-assembled and at the same time durable nano-structured materials like cohesive thin films. We report a new and simple method for the formation of thin films at the interface between aqueous silica ludox dispersion and lipid solutions in decane. The lipids used are stearic acid, stearyl amine and stearyl alcohol alongside silica ludox nanoparticle dispersions of varying pH. At basic pH thin films consisting of a mixture of stearic acid and silica nanoparticles precipitate at the interface. At acidic and neutral pH we were able to produce thin films consisting of stearyl amine and silica particles. Film growth was studied in situ by means of interfacial shear rheology, surface pressure isotherms and dynamic light scattering. The films all exhibit strong dynamic rheological moduli, which renders them an interesting material for applications such as capsule formation, surface coating or as functional membranes.

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See more of this Session: Aggregate and Agglomerate Nanoparticle Formation Dynamics
See more of this Group/Topical: Particle Technology Forum