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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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Reptation and constraint release dynamics in bidisperse polymer melts
Michael Langeloth1, Yuichi Masubuchi2, Michael C Böhm1
1Eduard-Zintl-Institut für Anorganische und Physikalische Chemie and Center of Smart Interfaces, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, D-64287 Darmstadt, Germany.
The Journal of Chemical Physics
|November 24, 2014
Summary
A new slip-spring model efficiently simulates entangled polymer blends. This method validates the tube dilation model, showing long chains reptate in an expanding tube when constraint release is significant.
Area of Science:
- Polymer Physics
- Computational Materials Science
Background:
- Understanding polymer dynamics in entangled melts is crucial for material properties.
- Existing simulation methods for polymer entanglement are computationally expensive.
Purpose of the Study:
- To develop and validate a computationally efficient slip-spring model for simulating bidisperse polymer melts.
- To investigate the influence of chain entanglement and constraint release on polymer dynamics.
Main Methods:
- Dissipative particle dynamics simulations were employed.
- A novel slip-spring approach was developed to mimic entanglement constraints.
- Simulations covered various weight fractions and entanglement conditions (Gr < 1.0 and Gr > 1.0).
Main Results:
- The slip-spring model shows good agreement with conventional methods for mean squared displacement but is significantly faster.
- For Gr > 1.0, long chains were observed to reptate within a dilated tube, supporting the tube dilation model.
- A linear relationship between relaxation time and weight fraction was found.
Conclusions:
- The slip-spring approach offers a computationally feasible alternative for large-scale polymer simulations.
- Simulation results provide strong evidence for the tube dilation model in bidisperse polymer melts under specific constraint release conditions.
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