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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
Physical re-examination of parameters on a molecular collisions-based diffusion model for diffusivity prediction in
Hidenori Ohashi1, Takanori Tamaki, Takeo Yamaguchi
1Chemical Resources Laboratory, Tokyo Institute of Technology, R1-17, Yokohama-city, Kanagawa 226-8503, Japan.
The Journal of Physical Chemistry. B
|November 16, 2011
Summary
A new diffusion theory models molecular collisions using shell-like free volume, predicting molecular diffusivity in polymers. This approach utilizes molecular volume and surface area for enhanced accuracy in diffusion studies.
Area of Science:
- Physical Chemistry
- Polymer Science
- Materials Science
Background:
- Molecular collisions drive diffusive motion, influenced by molecular surface area and intermolecular distances.
- The concept of "shell-like free volume" characterizes molecular collisions and free space.
- Existing diffusion models often require complex, multi-component parameters.
Purpose of the Study:
- To develop a novel diffusion theory based on molecular collision characteristics.
- To predict molecular diffusivity in polymeric systems using single-component parameters.
- To establish a more accurate and accessible model for diffusion in polymers.
Main Methods:
- Developed a new diffusion theory incorporating "shell-like free volume" as a key parameter.
- Utilized semiempirical quantum chemical calculations to determine molecular volume and surface area.
- Validated the model using well-defined single-component parameters: molecular volume, surface area, free volume, and pre-exponential factors.
Main Results:
- The new model successfully predicts molecular diffusivity in polymeric systems.
- The "shell-like free volume" effectively characterizes molecular collisions.
- The calculated molecular parameters demonstrated good predictive capability for the diffusion model.
Conclusions:
- The developed diffusion theory provides a robust framework for understanding and predicting molecular diffusion.
- The model's reliance on single-component parameters simplifies its application in polymer science.
- This approach offers a promising advancement in the field of molecular transport phenomena.
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