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Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
Energetic and entropic forces governing the attraction between polyelectrolyte-grafted colloids
1Department of Nanoengineering, University of California, San Diego, 9500 Gilman Drive, Mail Code: 0448, La Jolla, California 92093, USA.
The Journal of Physical Chemistry. B
|October 22, 2009
Summary
Computational study reveals attraction between like-charged colloidal particles grafted with oppositely charged polyelectrolyte chains. Attraction occurs within a hyperbolic region of colloid and polyelectrolyte charge space, driven by energetic and entropic forces.
Area of Science:
- Colloid and Interface Science
- Polymer Physics
- Computational Soft Matter
Background:
- Like-charged colloidal particles typically exhibit repulsion.
- Grafting oppositely charged polyelectrolyte chains can induce attraction.
- Understanding the interplay of energetic and entropic forces is crucial.
Purpose of the Study:
- Investigate the energetic and entropic interactions governing attraction between like-charged colloidal particles with grafted polyelectrolyte chains.
- Determine the conditions (charge space) under which attraction occurs.
- Develop a model to explain the observed attraction regime.
Main Methods:
- Employed coarse-grained models for colloids and polyelectrolyte chains.
- Utilized Monte Carlo simulations to compute the potential of mean force.
- Analyzed the two-dimensional parameter space of colloid surface and polyelectrolyte charge.
Main Results:
- Identified an attractive-force regime occupying the interior of a hyperbola in the charge space.
- Attraction strength depends on a balance of favorable polymer-bridging (energetic/entropic) and unfavorable repulsion/crowding (energetic/entropic) terms.
- The shape and size of the attractive regime are dictated by the interplay of energetic and entropic contributions.
Conclusions:
- A hyperbolic boundary defines the conditions for attraction between these complex colloidal systems.
- Energetic and entropic factors, including polymer bridging and chain confinement, govern the attraction.
- A proposed phenomenological model explains the hyperbolic attraction regime and predicts behavior under varied conditions.
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