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Updated: Jul 16, 2025
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
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Structure and dynamics of chemically active ring polymers: swelling to collapse
1Department of Physics, Indian Institute of Science Education and Research Bhopal, Bhopal 462066, India. namita18@iiserb.ac.in.
Soft Matter
|September 23, 2023
Summary
Chemically active rings can switch between attracting and repelling molecules, altering their structure from collapsed to swollen states. This active behavior enhances their dynamics, leading to faster relaxation and diffusion compared to passive rings.
Area of Science:
- Chemical physics
- Soft matter physics
- Computational chemistry
Background:
- Ring structures are prevalent in synthetic and natural systems.
- Chemical sensing influences local and long-range forces on these structures.
Purpose of the Study:
- Investigate structural and dynamical properties of chemically active rings.
- Understand how tuning chemical properties affects ring behavior in solvent.
- Compare active rings to passive counterparts.
Main Methods:
- Hybrid molecular dynamics (MD) and multiparticle collision dynamics (MPCD) simulations.
- Explicit solvent bath simulations.
- Analysis of scaling laws, local structures, and dynamics.
Main Results:
- Active rings can act as chemo-attractants or chemo-repellents.
- Tuning chemical activity alters steady-state conformations (collapsed or swelled).
- Active rings exhibit faster relaxation times and enhanced diffusion (mean squared displacement).
Conclusions:
- Chemical activity fundamentally alters ring structure and dynamics.
- The number of active sites influences the degree of collapse.
- Active rings display significantly different dynamic behavior than passive rings.
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