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08:12
Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
Demixing instability in coil-rod blends undergoing polycondensation reactions
P I C Teixeira1, D J Read, T C B McLeish
1Instituto Superior de Engenharia de Lisboa, Rua Conselheiro Emídio Navarro 1, P-1950-062 Lisbon, Portugal. piteixeira@cii.fc.ul.pt
The Journal of Chemical Physics
|March 3, 2007
Summary
This study investigates polymer blend stability, considering rod-like polymers that can form nematic liquid crystals. Researchers modeled blend stability during chemical reactions, finding it depends on polymer composition and interactions.
Area of Science:
- Polymer Science
- Materials Chemistry
- Physical Chemistry
Background:
- Previous work established models for reacting polymer blend stability concerning demixing.
- The current study expands this to include rod-like polymers capable of nematic ordering.
Purpose of the Study:
- To investigate the stability of reacting polymer blends containing rod-like polymers that can exhibit nematic ordering.
- To determine how factors like polymer composition, size, and nematic interactions influence blend stability.
Main Methods:
- Combines the random phase approximation for free energy calculations with a Markov chain model for chemical reactions.
- Calculates the spinodal (demixing boundary) as a function of reaction progress, assuming second-order chemical kinetics.
Main Results:
- Presents results for linear polymer systems, illustrating the impact of varying coil-to-rod proportions.
- Shows the effects of relative polymer sizes and the strength of nematic interactions between rod-like polymers on blend stability.
Conclusions:
- The stability of reacting polymer blends with nematic rod-like polymers is sensitive to composition and interaction parameters.
- The developed model provides insights into controlling phase behavior in complex polymer mixtures.
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