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Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

Published on: September 26, 2016

Internal dissipation of a polymer.

¹Department of Physics, University of California, Santa Cruz, California 95064, USA.

Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics

|September 28, 2010

Summary

This summary is machine-generated.

Internal friction significantly impacts flexible polymer dynamics, even without solvent. This study reveals damping characteristics distinct from Kelvin damping, showing underdamped motion persists with increased internal potentials.

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Area of Science:

Polymer Physics
Soft Matter Dynamics
Computational Biophysics

Background:

Polymer dynamics are typically modeled using solvent hydrodynamics.
Evidence suggests internal polymer dissipation also plays a crucial role.
Understanding internal friction is key to accurate polymer behavior prediction.

Purpose of the Study:

To investigate the dynamics of a single polymer chain without solvent.
To characterize the nature and contribution of internal friction.
To analyze the damping mechanisms in polymer chains.

Main Methods:

Modeling polymer chains as freely hinged segments.
Incorporating localized bond angles and dihedral angles.
Simulating chain dynamics to analyze damping properties.

Main Results:

Damping is similar but not identical to Kelvin damping.
Low internal potential leads to small damping and oscillatory behavior for long wavelengths.
Increased internal potential enhances damping but preserves underdamped motion for long wavelengths.

Conclusions:

Internal friction is a significant factor in polymer dynamics.
The damping mechanism differs from standard Kelvin damping.
Underdamped motion is observable even with substantial internal barriers.