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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Liquid crystal phase behavior of sterically-stabilized goethite.
Esther van den Pol1, Andrei V Petukhov, Dominique M E Thies-Weesie
1Van 't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute for Nanomaterials Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
Journal of Colloid and Interface Science
|October 1, 2010
Summary
Sterically-stabilized goethite particles in toluene exhibit rich liquid crystalline phase behavior, similar to charged particles in water. Toluene samples showed a tendency to form gels and smaller liquid crystalline domains.
Area of Science:
- Materials Science
- Colloid Science
- Soft Matter Physics
Background:
- Sterically-stabilized goethite nanoparticles offer tunable properties for advanced materials.
- Understanding nanoparticle phase behavior in organic solvents is crucial for developing new applications.
- Goethite's magnetic properties can be exploited in various technological fields.
Purpose of the Study:
- To investigate the liquid crystalline phase behavior of sterically-stabilized goethite particles in toluene.
- To compare this behavior with charged goethite particles in aqueous suspensions.
- To assess the retention of magnetic properties after particle surface modification.
Main Methods:
- Small-angle X-ray scattering (SAXS) was employed to study the liquid crystalline phases.
- Comparative analysis with data from charged goethite particles in water was performed.
- Magnetic field effects on particle alignment were investigated.
Main Results:
- Sterically-stabilized goethite in toluene displayed rich liquid crystalline phase behavior, comparable to charged particles in water.
- Surface coating with amino-functionalized polyisobutylene retained the particles' magnetic properties.
- Toluene samples exhibited a propensity for gel formation and smaller liquid crystalline domains, with the columnar phase incompletely developed.
Conclusions:
- Steric stabilization provides a viable route to achieve complex phase behavior in goethite nanoparticle suspensions.
- The choice of solvent significantly influences the liquid crystalline phase morphology and gelation tendency.
- Goethite nanoparticles maintain their magnetic responsiveness even after functionalization for organic media compatibility.
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