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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
Polymer immiscibility enhanced by thermal fluctuations toward crystalline order
Yu Ma1, Wenbing Hu, Howard Wang
1Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry, Nanjing University, 210093 Nanjing, China.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 13, 2007
Summary
Dynamic Monte Carlo simulations reveal that polymer blend immiscibility is enhanced by crystallization. Thermal fluctuations, not accounted for in mean-field theory, drive this enhanced phase separation in polymer blends.
Area of Science:
- Polymer Science
- Materials Science
- Computational Chemistry
Background:
- Binary polymer blends can undergo liquid-liquid phase separation.
- Crystallization of one component can influence phase behavior.
- Mean-field lattice theory provides a baseline prediction for phase separation.
Purpose of the Study:
- To investigate the effect of component crystallization on liquid-liquid phase separation in binary polymer blends.
- To compare simulation results with mean-field lattice theory predictions.
- To elucidate the role of thermal fluctuations in blend immiscibility.
Main Methods:
- Dynamic Monte Carlo simulations were employed.
- The study focused on binary polymer blends with one crystallizable component.
- Binodal and spinodal boundaries were analyzed.
Main Results:
- Liquid-liquid phase separation boundaries were observed to shift upwards compared to mean-field theory predictions.
- Enhanced immiscibility was detected in the polymer blends.
- This enhancement was attributed to thermal fluctuations promoting parallel ordering of crystallizable chains.
Conclusions:
- Thermal fluctuations play a crucial role in enhancing immiscibility in polymer blends near crystallization.
- Standard mean-field theory underestimates the effect of these fluctuations.
- The simulation findings provide a theoretical basis for understanding experimental observations in similar systems.
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