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Updated: May 21, 2025
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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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Rouse mode analysis of chain relaxation in reversibly crosslinked polymer melts
Rahul Karmakar1,2, Srikanth Sastry3, Sanat K Kumar4
1Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai 600036, India. tpatra@iitm.ac.in.
Physical Chemistry Chemical Physics : PCCP
|March 18, 2025
Summary
Reversibly crosslinked polymer melts exhibit distinct relaxation behaviors based on bond lifetimes. Shorter lifetimes lead to Rouse-like dynamics, while longer ones show two relaxation modes, with slower modes deviating from sticky Rouse model predictions.
Area of Science:
- Polymer Physics
- Materials Science
- Computational Chemistry
Background:
- Reversibly crosslinked polymer melts offer desirable properties like self-healing and reprocessability.
- Understanding their dynamic properties requires considering segmental and sticker association timescales.
Purpose of the Study:
- To investigate the relevance of the sticky Rouse model for polymer melts with reversible crosslinks.
- To examine the relaxation dynamics of these systems using hybrid simulations.
Main Methods:
- Hybrid molecular dynamics (MD)-Monte Carlo (MC) simulations were employed.
- The study analyzed polymer relaxation behavior as a function of bond lifetimes and chain length.
Main Results:
- Two distinct relaxation modes were observed depending on bond lifetimes.
- For shorter bond lifetimes, dynamics were Rouse-like with increased local friction.
- For longer bond lifetimes, a faster mode independent of lifetime and a slower, lifetime-dependent mode emerged, deviating from sticky Rouse model predictions.
Conclusions:
- The sticky Rouse model's predictions for slower relaxation modes are inconsistent with simulation results for short chains.
- Short chain effects need to be incorporated into theoretical models for accurate predictions in experimental systems.
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