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Updated: Aug 2, 2025
10:56
Confocal Imaging of Confined Quiescent and Flowing Colloid-polymer Mixtures
Published on: May 20, 2014
12.2K
Brownian motion of flexibly linked colloidal rings
Ruben W Verweij1, Julio Melio1, Indrani Chakraborty2
1Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands.
Physical Review. E
|April 19, 2023
Summary
Flexible colloidal rings exhibit faster diffusion than linear chains. Ring constraints decrease flexibility for smaller rings, impacting synthetic and biological polymer behavior.
Area of Science:
- Polymer Physics
- Soft Matter Physics
- Colloidal Science
Background:
- Ring polymers possess unique properties due to their closed topological structure, differing from linear polymers.
- Experimental characterization of cyclic polymer conformation and diffusion is challenging due to their small molecular size.
Purpose of the Study:
- To investigate the conformational and diffusive properties of a model system of flexible colloidal rings.
- To compare the behavior of ring polymers with linear polymer chains.
Main Methods:
- Utilized a model system of micron-sized colloidal particles linked flexibly into rings (n=4-8 segments).
- Characterized ring conformations and measured translational and rotational diffusion coefficients.
- Compared experimental results with hydrodynamic simulations.
Main Results:
- Flexible colloidal rings showed greater translational and rotational diffusion than linear colloidal chains.
- Internal deformation modes in rings exhibited slower fluctuations for smaller ring sizes (n≲8) compared to chains.
- Ring structure constraints were identified as the cause for decreased flexibility in smaller rings.
Conclusions:
- Flexible colloidal rings display distinct diffusive and conformational dynamics compared to linear chains.
- The study infers the scaling of flexibility with ring size, influenced by topological constraints.
- Findings have implications for understanding synthetic and biological ring polymers and floppy colloidal materials.
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