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Updated: Aug 6, 2026
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Confocal Imaging of Confined Quiescent and Flowing Colloid-polymer Mixtures
Published on: May 20, 2014
Columnar and lamellar phases in attractive colloidal systems
A de Candia1, E Del Gado, A Fierro
1Dipartimento di Scienze Fisiche, Università di Napoli Federico II, Complesso Universitario di Monte Sant'Angelo, 80126 Napoli, Italy.
Summary
Dynamical arrest in colloidal suspensions leads to gelation. However, the stable thermodynamic phase is crystalline columnar, with disordered networks ordering over time into this structure.
Area of Science:
- Soft Matter Physics
- Colloidal Science
- Materials Science
Background:
- Colloidal suspensions at low volume fraction and temperature exhibit dynamical arrest.
- Gelation in these systems is characterized by the formation of elongated structures and a connected network.
- The thermodynamic stability of phases during gelation has been a key question.
Purpose of the Study:
- To investigate the stable thermodynamic phase in colloidal suspensions undergoing gelation.
- To understand the structural evolution of the disordered network near the gelation threshold.
- To identify the final ordered structure formed from the gelled network.
Main Methods:
- Analysis of colloidal suspensions in a specific parameter space (low volume fraction and temperature).
- Observation of structural evolution from disordered networks to ordered phases.
- Thermodynamic phase identification.
Main Results:
- The stable thermodynamic phase in the gelation region is identified as crystalline columnar.
- Disordered spanning networks near and above the gelation threshold slowly evolve and order into the crystalline structure.
- At higher volume fractions, a lamellar phase is the stable state, exhibiting longer ordering times.
Conclusions:
- Gelation in colloidal suspensions does not represent the thermodynamically stable state.
- The system transitions from a disordered gelled network to an ordered crystalline columnar phase.
- The observed lamellar phase at higher concentrations suggests complex phase behavior and slower ordering dynamics.
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