| Abstract
| - A surfactant-based rigid gel mesophase containing bis(2-ethylhexyl) sodium sulfosuccinate (AOT),phosphatidylcholine (lecithin), 2,2,4-trimethylpentane (isooctane), and D2O has been characterized usingsmall angle neutron scattering (SANS). The addition of water to a solution of AOT and lecithin in isooctaneleads to a dramatic increase in viscosity and the formation of a rigid gel as the water content is increasedabove a specific threshold. SANS profiles indicate that these gels have a crystalline microstructure withcharacteristic dimensions that are clearly correlated to the system's water content and temperature. Thescattering patterns are consistent with models that describe the microstructure as columnar hexagonalat lower water contents and temperatures and lamellar at higher water contents and temperatures. SANSis also able to examine characteristics of the intermediate region where the two phases coexist and tocalculate the characteristic dimensions of these microstructures. The rigidity of the gel indicates that thesystem may be useful in templated materials synthesis.
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