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Aggregation of theta-polymers in spherical confinement
Johannes Zierenberg1, Marco Mueller1, Philipp Schierz1
1Institut für Theoretische Physik, Universität Leipzig, Postfach 100 920, 04009 Leipzig, Germany.
The Journal of Chemical Physics
|September 22, 2014
Summary
We studied theta polymer aggregation in confined spaces. Aggregation temperature depends on density and system size, allowing predictions for dilute polymer solutions.
Area of Science:
- Polymer Physics
- Statistical Mechanics
- Computational Chemistry
Background:
- Theta polymers exhibit complex phase behavior, including aggregation.
- Spherical confinement introduces geometric constraints affecting polymer interactions.
- Understanding aggregation is crucial for polymer solution properties.
Purpose of the Study:
- Investigate the aggregation transition of theta polymers within spherical confinement.
- Systematically analyze the influence of polymer density on aggregation temperature.
- Determine the interplay between single-polymer collapse and aggregation.
Main Methods:
- Utilized multicanonical simulations for comprehensive phase space exploration.
- Simulated systems with up to 24 monodisperse theta polymers.
- Analyzed entropic and energetic contributions to aggregation.
Main Results:
- Aggregation transition temperature is density-dependent.
- Identified a lower temperature bound for the isolated chain approximation.
- Demonstrated finite-size effects on aggregation in confined systems.
Conclusions:
- Density and system size are key factors governing theta polymer aggregation in confinement.
- Developed a method to estimate aggregation temperature using small, dilute systems.
- Provided insights into the competition between collapse and aggregation phenomena.
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