Self-Assembled Organogels
Tulane University, Dept of Chemical & Biomolecular Engineering
  :: Background

A novel organogel is formed when the surfactant AOT is dissolved in a nonpolar solvent together with a substituted acidic phenol in a 1:1 molar ratio. There is a dramatic transformation from a low viscosity liquid (0.006Pa.s) to the organogel (30000Pa.s) upon addition of the phenolic component.

Hydrogen bonding between the phenol and the carbonyl groups of the AOT are the basic force behind self-assembly and gelation.

Organogels can range from clear to turbid, depending on the choice of non-polar solvent. 

 

 :: Gel Formation Process

 

Probing of the gel microstructure using various techniques e.g. XRD, NMR, SAXS and AFM suggests that the gel strands initially aggregate into fibers (~10nm) which then gelates further to form fiber bundles of 20-100nm widths .



 ::

Incorporation of nanoparticles into the gel structure can be achieved by first forming the nanoparticles in the aqueous pools of the AOT reverse micelles, followed by stripping of the water by drying. Upon reconstitution with an appropriate non-polar solvent, the corresponding organogel can be formed which shows incorporation of nanoparticles into the gel structure. 

A photograph of the blank gel, and gels containing CdS and ferrite particles is shown below:




BACK



© Vijay John's Research Group