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Updated: May 17, 2026
06:55
Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Entropic alignment of topologically modified ring polymers in cylindrical confinement.
Sanjay Bhandarkar1, Debarshi Mitra1, Jürgen Horbach2
1IISER-Pune, Department of Physics, Dr. Homi Bhabha Road, Pashan, Pune, Maharashtra 411008, India.
Physical Review. E
|May 16, 2026
Summary
Ring polymers with internal loops localize along cylinder axes due to entropic repulsion. This topological modification drives polymer organization and neighbor orientation, mimicking Ising spins without enthalpy changes.
Area of Science:
- Soft Matter Physics
- Polymer Physics
- Statistical Mechanics
Background:
- Topological modifications in ring polymers can influence their organization.
- Entropic forces play a crucial role in the self-assembly of polymers.
- Bacterial chromosome organization principles can be informed by polymer physics.
Purpose of the Study:
- To investigate how internal loops in ring polymers affect their spatial organization and orientation under cylindrical confinement.
- To explore the role of entropic interactions in driving polymer self-organization.
- To establish a link between polymer topology, entropic forces, and emergent orientational interactions.
Main Methods:
- Simulating flexible polymers using a bead-spring model with repulsive excluded volume interactions.
- Introducing internal loops of varying sizes to modify polymer topology and create asymmetry.
- Analyzing polymer segment localization, orientation, and inter-polymer interactions using free-energy calculations.
Main Results:
- Internal loops cause ring polymers to localize along the cylinder's long axis due to entropic repulsion.
- Polymers exhibit emergent orientational ordering, aligning with neighbors along the cylinder axis, akin to Ising spin interactions.
- This organization is driven purely by entropy, not enthalpy, with only repulsive monomer-monomer interactions.
Conclusions:
- Harnessing entropic interactions via topological manipulation (internal loops) can induce effective orientational interactions in flexible polymers.
- The findings provide insights into the mechanisms of polymer organization in confined environments.
- The principles may be applicable to understanding complex biological structures like bacterial chromosomes and interactions within large DNA loops.
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