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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
A distribution kinetics approach for crystallization of polymer blends
Jiao Yang1, Benjamin J McCoy, Giridhar Madras
1Department of Chemical Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
The Journal of Physical Chemistry. B
|August 4, 2006
Summary
This study models polymer blend crystallization kinetics, showing how blending affects crystal formation and growth. Blending influences nucleation and crystal growth rates, with results validated against experimental data.
Area of Science:
- Polymer Science
- Materials Science
- Physical Chemistry
Background:
- Crystallization kinetics in polymer blends are complex due to polymer-polymer interactions.
- Understanding these kinetics is crucial for tailoring material properties.
- Existing models often simplify the impact of blend composition on crystallization.
Purpose of the Study:
- To extend the cluster distribution approach for modeling polymer blend crystallization kinetics.
- To incorporate mixture effects of polymer-polymer interactions into diffusion coefficients.
- To investigate the influence of blending fractions on crystallization behavior and validate the model.
Main Methods:
- Extended cluster distribution approach.
- Incorporation of polymer-polymer interactions into the diffusion coefficient.
- Modeling of temperature, activation energy, and enthalpy dependence on blending fraction.
- Simulation of poly(vinylidenefluoride)[PVDF] and poly(vinyl acetate)[PVAc] blend crystallization.
Main Results:
- Crystallization kinetics exhibit characteristic behavior dependent on blending fraction.
- Avrami equation can approximately describe overall crystallization kinetics.
- Nucleation rate decreases with increasing blending fraction of the second polymer.
- Blending affects crystal growth rate via deposition-rate driving force and growth-rate coefficient.
Conclusions:
- The developed model accurately captures the influence of blending fractions on crystallization kinetics.
- The study provides insights into how polymer blending modifies nucleation and crystal growth.
- Model validation with experimental data confirms its predictive capability for polymer blend crystallization.
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